Journal articles
Witt M, Godley B, Pikesley S (In Press). A novel approach to estimate the distribution, density and at-sea risks of a
centrally-placed mobile marine vertebrate. Biological Conservation
Varela MR, Patricio AR, Anderson K, Broderick AC, DeBell L, Hawkes LA, Tilley D, Snape R, Westoby MJ, Godley BJ, et al (In Press). Assessing climate change associated sea level rise impacts on sea turtle nesting beaches using drones, photogrammetry and a novel GPS system. Global Change Biology
Witt M, Godley B, Bicknell A, Doherty P, Sheehan E (In Press). Assessing the impact of introduced infrastructure at sea with cameras: a case study for spatial scale, time and statistical power. Marine Environmental Research
Witt M, Godley BJ (In Press). Basking shark breaching behaviour observations West of Shetland. Marine Biodiversity Records
Duncan E, Arrowsmith JA, Bain CE, Bowdery H, Broderick A, Chalmers T, Fuller WJ, Galloway T, Lee JH, Lindeque PK, et al (In Press). Diet-related selectivity of macroplastic ingestion in green turtles (Chelonia mydas) in the eastern Mediterranean. Scientific Reports
Weber SB, Richardson AJ, Brown J, Bolton M, Clark B, Godley B, Leat EHK, Oppel S, Soetaert KER, Weber N, et al (In Press). Direct evidence of a prey depletion ‘halo’ surrounding a pelagic predator colony. Proceedings of the National Academy of Sciences of USA
Patricio AR, Formia A, Barbosa C, Broderick AC, Bruford M, Carreras C, Catry P, Ciofi C, Regalla A, Godley BJ, et al (In Press). Dispersal of green turtles from Africa’s largest rookery assessed through genetic markers. Marine Ecology Progress Series
Bjorndal KA, Bolten AB, Chaloupka M, Saba VS, Bellini C, Marcovaldi MAG, Santos AJ, Bortolon LFW, Meylan AB, Meylan PA, et al (In Press). Ecological regime shift drives declining growth rates of sea turtles throughout the West Atlantic. Global Change Biology
Godley BJ, Galloway T, Parton K (In Press). Global review of shark and ray entanglement in anthropogenic marine debris. Endangered Species Research
Patino-Martinez J, Marco A, Quinones L, Godley BJ (In Press). Globally significant nesting of the leatherback turtle (Dermochelys coriacea) on the Caribbean coast of Colombia and Panama. (for pre-print please contact juanpatino@ebd.csic.es). Biological Conservation
Blumenthal, J.M. Austin, T.J. Ebanks-Petrie, G. (In Press). Harnessing recreational divers for the collection of sea turtle data around the Cayman Islands. Tourism in Marine Environments
Patino-Martinez J, Godley BJ, Quinones L, Marco A (In Press). Impact of tropical forest logging on the reproductive success of leatherback turtles. Marine Ecology Progress Series
Nelms S, Godley B, Richardson P, Eyles L, Solandt J-L, Selley H, Witt M (In Press). Investigating the distribution and regional occurrence of anthropogenic litter in English Marine Protected Areas using 25 years of citizen-science beach clean data. Environmental Pollution
Rees AF, Carreras C, Broderick AC, Margaritoulis D, Stringell T, Godley BJ (In Press). Linking loggerhead locations: using multiple methods to determine the origin of sea turtles in feeding grounds. Marine Biology
Doherty PD, Baxter JM, Gell FR, Godley BJ, Graham RT, Hall G, Hall J, Hawkes LA, Henderson SM, Johnson L, et al (In Press). Long-term satellite tracking reveals variable seasonal migration strategies of basking sharks in the north-east Atlantic. Scientific Reports
Godley BJ, Witt MJ, Galloway TS, Nelms SE, Coombes C, Foster LC, Lindeque PK (In Press). Marine anthropogenic litter on British beaches: a 10-year nationwide assessment using citizen science data. Science of the Total Environment
Walker JMM, Godley BJ, Nuno A (In Press). Media framing of the Cayman Turtle Farm: implications for conservation conflicts. Journal for Nature Conservation
Duncan E, Davies A, Brooks A, Wahidunnessa Chowdhury G, Godley B, Jambeck J, Maddalene T, Napper I, Nelms S, Rackstraw C, et al (In Press). Message in a bottle: open source technology to track the movement of plastic pollution. PLoS One
Omeyer L, McKinley TJ, Bréheret N, Bal G, Petchell Balchin G, Bitsindou A, Chauvet E, Collins T, Curran BK, Formia A, et al (In Press). Missing Data in Sea Turtle Population Monitoring: a Bayesian Statistical Framework Accounting for Incomplete Sampling. Frontiers in Marine Science, 9
Chevis MG, Godley BJ, Lewis JP, Lewis JJ, Scales KL, Graham RT (In Press). Movement patterns of juvenile hawksbill turtles (Eretmochelys imbricata) at a Caribbean coral atoll: long-term tracking using passive acoustic telemetry. Endangered Species Research
Stevens M, Broderick AC, Godley BJ, Lown AE, Troscianko J, Weber N, Weber SB (In Press). Phenotype-Environment Matching in Sand Fleas. Biology Letters
Jones J, Porter A, Muñoz-Pérez J, Alarcón-Ruales D, Galloway T, Godley B, Santillo D, Vagg J, Lewis C (In Press). Plastic contamination of the Galapagos marine food web and the relative risks to native species.
Abstract:
Plastic contamination of the Galapagos marine food web and the relative risks to native species
Abstract
. Ecuador’s Galapagos Islands and their unique biodiversity are a global conservation priority. We investigated the presence, partitioning and environmental drivers of plastic contamination across the marine ecosystem, designing a systematic risk scoring analysis to identify the most vulnerable species. Beach contamination varied by site (macroplastic 0 - 0.66 items.m-2, large microplastics 0 - 448.8 particles.m-2, small microplastics 0 – 74.6 particles.kg-1), with high plastic accumulation on east-facing beaches indicating input from the Humboldt Current. Local littering and waste management leakages accounted for 2% of macroplastic. Microplastics (including synthetic cellulosics) were prevalent in sediments (6.7 - 86.7 particles.kg-1) and surface seawater (0.04 - 0.89 particles.m-3), with elevated concentrations in the harbour suggesting local input. Microplastics were present in all seven marine invertebrate species examined, found in 52% of individuals (n = 123). Risk scoring identified 32 species in need of urgent, targeted monitoring and mitigation including pinnipeds, seabirds, turtles, sharks and corals.
Abstract.
Omeyer L, Godley B (In Press). Priorities to inform research on marine plastic pollution in Southeast Asia. Science of the Total Environment
Stringell TB, Clerveaux WV, Godley BJ, Phillips Q, Ranger S, Richardson PB, Sanghera A, Broderick AC (In Press). Protecting the breeders: research informs legislative change in a marine turtle fishery.
Biodiversity and ConservationAbstract:
Protecting the breeders: research informs legislative change in a marine turtle fishery
Marine turtles are sensitive to harvesting because of life-cycle traits such as longevity, late maturity and natal philopatry. The take of nesting females is of conservation concern because they are key to population maintenance and has led to global efforts to protect this life stage. In the Turks and Caicos Islands (TCI; a UK Overseas Territory in the Caribbean), previous turtle fishery legislation protected nesting turtles on the beach but not in the water, where turtles over a minimum size were subject to legal take. In a 2-year study, we undertook nesting beach and in-water surveys, molecular analyses, satellite tracking and collation of fisheries landing data to investigate the populations of green
(Chelonia mydas) and hawksbill (Eretmochelys imbricata) turtles in the TCI and its turtle fishery. Adults were frequently taken in one of the region’s largest legal and artisanal turtle fisheries. We suggest that nesting populations in the TCI, which contain genetically unique
haplotypes, have diminished since the 1980s, likely as a result of the harvest of adults. Using these multiple lines of evidence, we highlight the inadequacies of the former fishery regulations and propose specific legislative amendments, which, as a result of this study, were implemented on 1 July 2014 by the TCI government. With good enforcement, these measures will protect adults breeding in the TCI and those from nesting rookeries in the region that use the waters of the TCI, improve the management of this fishery, and safeguard fisher livelihoods.
Abstract.
Ortiz N, Mangel JC, Wang J, Alfaro-Shigueto J, Pingo S, Jimenez A, Suarez T, Swimmer Y, Carvalho F, Godley BJ, et al (In Press). Reducing green turtle bycatch in small-scale fisheries using illuminated gillnets: the Cost of Saving a Sea Turtle.
Marine Ecology Progress SeriesAbstract:
Reducing green turtle bycatch in small-scale fisheries using illuminated gillnets: the Cost of Saving a Sea Turtle
Gillnet fisheries exist throughout the oceans and have been implicated in high bycatch rates of sea turtles. In this study, we examined the effectiveness of illuminating nets with light-emitting diodes (LEDs), placed on floatlines in order to reduce sea turtle bycatch in a small-scale bottom-set gillnet fishery. In Sechura Bay, Northern Peru, 114 pairs of control and illuminated nets were deployed. The predicted mean Catch Per Unit of Effort (CPUE) of target species, standardized for environmental variables using generalized additive model analysis, was similar for both control and illuminated nets. In contrast, the predicted mean CPUE of green turtles (Chelonia mydas) was reduced by 63.9% in illuminated nets. One hundred twenty-five green turtles were caught in control nets while 62 were caught in illuminated nets. This statistically significant reduction (GAM analysis, p
Abstract.
Votier SC, Grecian WJ, Witt MJ, Bearhop, Attrill M, Godley BJ (In Press). Seabird diversity hotspot linked to ocean productivity in the Canary Current Large Marine Ecosystem. Biology Letters
Broderick, A.C. Godley, B.J. (In Press). Seabird populations of the Chagos Archipelago: an evaluation of IBA sites and a need for monitoring. (For preprint contact a.mcgowan@ex.ac.uk). Oryx
Doherty P, Hawkes LA, Godley BJ, Witt M, Henderson S, Graham R, Hall J, Hall G, Speedie C, Johnson L, et al (In Press). Seasonal changes in basking shark vertical space-use in the north-east Atlantic. Marine Biology
Haywood JC, Fuller WJ, Godley B, Margaritoulis D, Shutler J, Snape RTE, Widdicombe S, Zbinden J, Broderick A (In Press). Spatial ecology of loggerhead turtles: Insights from stable isotope markers and satellite telemetry. Diversity and Distributions: a journal of conservation biogeography
Scott R, Biastoch A, Agamboue PD, Bayer T, Boussamba FI, Formia A, Godley BJ, Mabert BDK, Manfoumbi JC, Schwarzkopf FU, et al (In Press). Spatiotemporal variation in ocean current driven hatchling dispersion: implications for the world’s largest leatherback sea turtle nesting region. Diversity and Distributions
Doherty PD, Baxter JM, Godley BJ, Graham RT, Hall G, Hall J, Hawkes LA, Henderson SM, Johnson L, Witt MJ, et al (In Press). Testing the boundaries: Seasonal residency and inter-annual site fidelity of basking sharks in a proposed marine protected area. Biological Conservation
Omeyer LCM, Duncan EM, Aiemsomboon K, Beaumont N, Bureekul S, Cao B, Carrasco LR, Chavanich S, Clark JR, Cordova MR, et al (2023). Corrigendum to “Priorities to inform research on marine plastic pollution in Southeast Asia” [Sci. Total Environ. volume 841 (2022) Article 156704] (Science of the Total Environment (2022) 841, (S0048969722038013), (10.1016/j.scitotenv.2022.156704)).
Science of the Total Environment,
857Abstract:
Corrigendum to “Priorities to inform research on marine plastic pollution in Southeast Asia” [Sci. Total Environ. volume 841 (2022) Article 156704] (Science of the Total Environment (2022) 841, (S0048969722038013), (10.1016/j.scitotenv.2022.156704))
The authors regret that the printed version of the above article contained a number of errors. The correct and final version follows. The authors would like to apologise for any inconvenience caused. The edits to Fig. 4 are as follow: - the scale of the ‘Annual River Emissions’ scatter was one order of magnitude off due to scaling the scatter down to an appropriate size.- the unit of measurement of the ‘National Riverine Plastic Emissions’ is tonnes per year.
Abstract.
Kaska A, Koç G, Sözbilen D, Salih D, Glidan A, Elsowayeb AA, Saied A, Margaritoulis D, Theodorou P, Rees A, et al (2023). Increased sample size provides novel insights into population structure of Mediterranean loggerhead sea turtles. Conservation Genetics Resources, 1-9.
Omeyer LCM, Duncan EM, Abreo NAS, Acebes JMV, AngSinco-Jimenez LA, Anuar ST, Aragones LV, Araujo G, Carrasco LR, Chua MAH, et al (2023). Interactions between marine megafauna and plastic pollution in Southeast Asia. Science of the Total Environment, 874, 162502-162502.
Catry P, Senhoury C, Sidina E, El Bar N, Bilal AS, Ventura F, Godley BJ, Pires AJ, Regalla A, Patrício AR, et al (2023). Satellite tracking and field assessment highlight major foraging site for green turtles in the Banc d'Arguin, Mauritania. Biological Conservation, 277, 109823-109823.
Sandbrook C, Fisher M, Cumming GS, Evans KL, Glikman JA, Godley BJ, Jarrad F, Polunin N, Murcia C, Pérez-Ruzafa A, et al (2023). The role of journals in supporting the socially responsible use of conservation technology. Oryx, 57(1), 1-2.
Sandbrook C, Fisher M, Cumming GS, Evans KL, Glikman JA, Godley BJ, Jarrad F, Polunin N, Murcia C, Perez-Ruzafa A, et al (2023). The role of journals in supporting the socially responsible use of conservation technology.
ORYX,
57(1), 1-2.
Author URL.
Herbert-Read JE, Thornton A, Amon DJ, Birchenough SNR, Côté IM, Dias MP, Godley BJ, Keith SA, McKinley E, Peck LS, et al (2022). A global horizon scan of issues impacting marine and coastal biodiversity conservation.
Nat Ecol Evol,
6(9), 1262-1270.
Abstract:
A global horizon scan of issues impacting marine and coastal biodiversity conservation.
The biodiversity of marine and coastal habitats is experiencing unprecedented change. While there are well-known drivers of these changes, such as overexploitation, climate change and pollution, there are also relatively unknown emerging issues that are poorly understood or recognized that have potentially positive or negative impacts on marine and coastal ecosystems. In this inaugural Marine and Coastal Horizon Scan, we brought together 30 scientists, policymakers and practitioners with transdisciplinary expertise in marine and coastal systems to identify new issues that are likely to have a significant impact on the functioning and conservation of marine and coastal biodiversity over the next 5-10 years. Based on a modified Delphi voting process, the final 15 issues presented were distilled from a list of 75 submitted by participants at the start of the process. These issues are grouped into three categories: ecosystem impacts, for example the impact of wildfires and the effect of poleward migration on equatorial biodiversity; resource exploitation, including an increase in the trade of fish swim bladders and increased exploitation of marine collagens; and new technologies, such as soft robotics and new biodegradable products. Our early identification of these issues and their potential impacts on marine and coastal biodiversity will support scientists, conservationists, resource managers and policymakers to address the challenges facing marine ecosystems.
Abstract.
Author URL.
DiMatteo A, Cañadas A, Roberts J, Sparks L, Panigada S, Boisseau O, Moscrop A, Fortuna CM, Lauriano G, Holcer D, et al (2022). Basin-wide estimates of loggerhead turtle abundance in the Mediterranean Sea derived from line transect surveys. Frontiers in Marine Science, 9
Al Ameri H, Al Harthi S, Al Kiyumi A, Al Sariri T, Al-Zaidan A, Antonopoulou M, Broderick A, Chatting M, Das H, Hesni M, et al (2022). Biology and conservation of marine turtles in the northwestern Indian Ocean: a review. Endangered Species Research, 48, 67-86.
Al Ameri H, Al Harthi S, Al Kiyumi A, Al Sariri T, Al-Zaidan A, Antonopoulou M, Broderick A, Chatting M, Das H, Hesni M, et al (2022). CORRIGENDUM: Biology and conservation of marine turtles in the northwestern Indian Ocean: a review. Endangered Species Research, 48
Campbell E, Alfaro-Shigueto J, Aliaga-Rossel E, Beasley I, Briceño Y, Caballero S, da Silva V, Gilleman C, Gravena W, Hines E, et al (2022). Challenges and priorities for river cetacean conservation. Endangered Species Research, 49, 13-42.
Duncan EM, Davies A, Brooks A, Chowdhury GW, Godley BJ, Jambeck J, Maddalene T, Napper I, Nelms SE, Rackstraw C, et al (2022). Correction: Message in a bottle: Open source technology to track the movement of plastic pollution. PLOS ONE, 17(5).
Darmon G, Schulz M, Matiddi M, Loza AL, Tòmàs J, Camedda A, Chaieb O, El Hili HA, Bradai MN, Bray L, et al (2022). Drivers of litter ingestion by sea turtles: Three decades of empirical data collected in Atlantic Europe and the Mediterranean.
Marine Pollution Bulletin,
185Abstract:
Drivers of litter ingestion by sea turtles: Three decades of empirical data collected in Atlantic Europe and the Mediterranean
Sea turtles are considered as bio-indicators for monitoring the efficiency of restoration measures to reduce marine litter impacts on health. However, the lack of extended and standardised empirical data has prevented the accurate analysis of the factors influencing litter ingestion and the relationships with individual health. Historic data collected from 1988 and standard data collected from 2016 were harmonised to enable such analyses on necropsied loggerhead turtles (Caretta caretta) in eight Mediterranean and North-East Atlantic countries. Litter was found in 69.24 % of the 1121 individuals, mostly single-use and fishing-related plastics. Spatial location, sex and life history stage explained a minor part of litter ingestion. While no relationships with health could be detected, indicating that all individuals can be integrated as bio-indicators, the mechanistic models published in literature suggest that the high proportion of plastics in the digestive contents (38.77 % per individual) could have long-term repercussions on population dynamics.
Abstract.
Doherty PD, Enever R, Omeyer LCM, Tivenan L, Course G, Pasco G, Thomas D, Sullivan B, Kibel B, Kibel P, et al (2022). Efficacy of a novel shark bycatch mitigation device in a tuna longline fishery.
Current Biology,
32(22), R1260-R1261.
Abstract:
Efficacy of a novel shark bycatch mitigation device in a tuna longline fishery
Elasmobranchs (sharks, rays, and skates) are caught throughout fisheries globally, leading to over one-third of species being threatened with extinction1. Oceanic shark populations have undergone an average 71% decline over the last half century, owing to an 18-fold increase in relative fishing pressure2. Incidental capture or ‘bycatch’ is a primary driver of population declines, and poses an important challenge for species conservation3. This threat necessitates mitigation strategies that exist for sharks but are often focussed on haul-back and post-capture effects for longline fishing. We trialled a novel shark bycatch mitigation device (“SharkGuard”) in a commercial longline fishery targeting bluefin tuna (Thunnus thynnus), where bycatch consists largely of blue sharks (Prionace glauca) and pelagic stingrays (Pteroplatytrygon violacea).
Abstract.
Jorgensen S, Micheli F, White T, Van Houtan K, Alfaro-Shigueto J, Andrzejaczek S, Arnoldi N, Baum J, Block B, Britten G, et al (2022). Emergent research and priorities for shark and ray conservation. Endangered Species Research, 47, 171-203.
Metcalfe K, White L, Lee ME, Fay JM, Abitsi G, Parnell RJ, Smith RJ, Agamboue PD, Bayet JP, Mve Beh JH, et al (2022). Fulfilling global marine commitments; lessons learned from Gabon. Conservation Letters, 15(3).
Senko JF, Burgher KM, Mancha-Cisneros MDM, Godley BJ, Kinan-Kelly I, Fox T, Humber F, Koch V, Smith AT, Wallace BP, et al (2022). Global patterns of illegal marine turtle exploitation.
GLOBAL CHANGE BIOLOGY,
28(22), 6509-6523.
Author URL.
Patricio AR, Beal M, Barbosa C, Diouck D, Godley BJ, Madeira FM, Regalla A, Traore MS, Senhoury C, Sidina E, et al (2022). Green Turtles Highlight Connectivity Across a Regional Marine Protected Area Network in West Africa.
FRONTIERS IN MARINE SCIENCE,
9 Author URL.
Pritchard A, Sanchez C, Bunbury N, Burt A, Currie J, Doak N, Fleischer-Dogley F, Metcalfe K, Mortimer J, Richards H, et al (2022). Green turtle population recovery at Aldabra Atoll continues after 50 yr of protection. Endangered Species Research, 47, 205-215.
de Geer C, Bourjea J, Broderick A, Dalleau M, Fernandes R, Harris L, Inteca G, Kiponda F, Louro C, Mortimer J, et al (2022). Marine turtles of the African east coast: current knowledge and priorities for conservation and research. Endangered Species Research, 47, 297-331.
Snape RTE, Beton D, Davey S, Godley BJ, Haywood J, Omeyer LCM, Ozkan M, Broderick AC (2022). Mediterranean green turtle population recovery increasingly depends on Lake Bardawil, Egypt.
Global Ecology and Conservation,
40Abstract:
Mediterranean green turtle population recovery increasingly depends on Lake Bardawil, Egypt
To assign conservation status to a population, its size, trends, and distribution must be estimated. The Mediterranean green turtle population has shown signs of recovering over the past decade, likely in response to nest protection, but satellite tracking suggests adult foraging remains largely restricted to only a few key sites in the eastern Mediterranean. Previous research suggested that the majority of green turtles nesting at an important rookery in Cyprus, forage in Lake Bardawil, Egypt making an observed population increase dependent on this important site, which is under a high degree of anthropogenic maintenance. Here we provide new data that further demonstrates the importance of Lake Bardawil to green turtles that nest at other major rookeries on Cyprus, in the Karpaz Peninsula, with 74 % of satellite tracked females (n = 19) migrating to this key site. We also report on the first systematic nest counts for this area in over two decades and identify the inter-nesting habitat used by females nesting at these important beaches on the north and south coasts of the Peninsula. Comparing the oldest available 3-year nest count averages (1993–1995), with nest counts undertaken as part of this study (2017–2019), mean annual nest numbers increased from 186 to 554, an increase of 198 %. Our data confirm the continued importance of these beaches for the Mediterranean green turtle population and underscore the reliance of this endangered population on a man-made lagoon for recent increases in clutch counts at monitored beaches. The results highlight the utility of satellite telemetry to inform conservation status assessments and establishing conservation at both nesting and foraging sites across the population.
Abstract.
Conners MG, Sisson NB, Agamboue PD, Atkinson PW, Baylis AMM, Benson SR, Block BA, Bograd SJ, Bordino P, Bowen WD, et al (2022). Mismatches in scale between highly mobile marine megafauna and marine protected areas. Frontiers in Marine Science, 9
Kot CY, Åkesson S, Alfaro‐Shigueto J, Amorocho Llanos DF, Antonopoulou M, Balazs GH, Baverstock WR, Blumenthal JM, Broderick AC, Bruno I, et al (2022). Network analysis of sea turtle movements and connectivity: a tool for conservation prioritization. Diversity and Distributions, 28(4), 810-829.
Enever R, Doherty PD, Ashworth J, Duffy M, Kibel P, Parker M, Stewart BD, Godley BJ (2022). Scallop potting with lights: a novel, low impact method for catching European king scallop (Pecten maximus). Fisheries Research, 252
Enever R, Doherty PD, Ashworth J, Duffy M, Kibel P, Parker M, Stewart BD, Godley BJ (2022). TEMPORARY REMOVAL: Scallop potting with lights: a novel, low impact method for catching European king scallop (Pecten maximus).
FISHERIES RESEARCH,
252 Author URL.
Gough C, Ateweberhan M, Godley BJ, Harris A, Le Manach F, Zafindranosy E, Broderick AC (2022). Temporal Change and Fishing Down Food Webs in Small-Scale Fisheries in Morondava, Madagascar. Frontiers in Marine Science, 9
Barbanti A, Blumenthal JM, Broderick AC, Godley BJ, Prat-Varela A, Turmo M, Pascual M, Carreras C (2022). The architecture of assisted colonisation in sea turtles: building new populations in a biodiversity crisis.
Nat Commun,
13(1).
Abstract:
The architecture of assisted colonisation in sea turtles: building new populations in a biodiversity crisis.
Due to changing environmental conditions, many species will have to migrate or occupy new suitable areas to avoid potential extinction in the current biodiversity crisis. Long-lived animals are especially vulnerable and ex-situ conservation actions can provide solutions through assisted colonisations. However, there is little empirical evidence on the process of founding new populations for such species or the feasibility of assisted colonisations as a viable conservation measure. Here, we combined genetics with reproductive data to study the rise of two wild populations of green turtles (Chelonia mydas) in the Cayman Islands as a possible outcome of a reintroduction program started 50 years ago. We show that both populations are highly related to the captive population but rapidly diverged due to genetic drift. Individuals from the reintroduced populations showed high levels of nest fidelity, within and across nesting seasons, indicating that philopatry may help reinforce the success of new populations. Additionally, we show that reintroduction from captive populations has not undermined the reproductive fitness of first generation individuals. Sea turtle reintroduction programs can, therefore, establish new populations but require scientific evaluation of costs and benefits and should be monitored over time to ensure viability in the long-term.
Abstract.
Author URL.
Ford HV, Jones NH, Davies AJ, Godley BJ, Jambeck JR, Napper IE, Suckling CC, Williams GJ, Woodall LC, Koldewey HJ, et al (2022). The fundamental links between climate change and marine plastic pollution.
Science of the Total Environment,
806Abstract:
The fundamental links between climate change and marine plastic pollution
Plastic pollution and climate change have commonly been treated as two separate issues and sometimes are even seen as competing. Here we present an alternative view that these two issues are fundamentally linked. Primarily, we explore how plastic contributes to greenhouse gas (GHG) emissions from the beginning to the end of its life cycle. Secondly, we show that more extreme weather and floods associated with climate change, will exacerbate the spread of plastic in the natural environment. Finally, both issues occur throughout the marine environment, and we show that ecosystems and species can be particularly vulnerable to both, such as coral reefs that face disease spread through plastic pollution and climate-driven increased global bleaching events. A Web of Science search showed climate change and plastic pollution studies in the ocean are often siloed, with only 0.4% of the articles examining both stressors simultaneously. We also identified a lack of regional and industry-specific life cycle analysis data for comparisons in relative GHG contributions by materials and products. Overall, we suggest that rather than debate over the relative importance of climate change or marine plastic pollution, a more productive course would be to determine the linking factors between the two and identify solutions to combat both crises.
Abstract.
Nelms SE, Easman E, Anderson N, Berg M, Coates S, Crosby A, Eisfeld-Pierantonio S, Eyles L, Flux T, Gilford E, et al (2022). The role of citizen science in addressing plastic pollution: Challenges and opportunities.
Environmental Science and Policy,
128, 14-23.
Abstract:
The role of citizen science in addressing plastic pollution: Challenges and opportunities
Globally, the number of citizen science clean-up projects, such as beach cleans, is increasing in an effort to reduce the amount of plastic pollution in the environment. Such activities offer the opportunity to gather insightful data on plastic abundance, distribution and composition. This information is key for informing effective management strategies aimed at reducing input but little work has been conducted to examine the challenges faced by existing citizen science projects, or the potential opportunities for maximising their impact. Here, we present the results of a questionnaire survey and follow-up workshop to explore the opinions of representatives from 20 organisations that deal with the issue of plastic pollution in the environment. Our results show that, of the organisations that conduct clean-up activities in the United Kingdom (UK), the majority collect data on plastic pollution to some extent. To ensure these data are scientifically meaningful and the necessary levels of public engagement are maintained, participants felt that survey protocols should be standardised across organisations and data submission should be as simple and easy as possible. The participants considered communication, inclusivity and volunteer diversity to be key for enhancing citizen engagement and improving data quality. Many organisations were unclear about how the information they hold can be most effectively used to help inform policies relating to managing plastic pollution. Moving forwards, there is a clear desire from clean-up organisations to collaborate with other sectors, such as commercial, policy, waste and recycling, education and technology stakeholders, as well as other non-governmental organisations and scientific researchers, to enhance the value and impact of citizen science in tackling the issue of plastic pollution.
Abstract.
Cooke SJ, Lennox RJ, Brownscombe JW, Iverson SJ, Whoriskey FG, Millspaugh JJ, Hussey NE, Crossin GT, Godley BJ, Harcourt R, et al (2021). A case for restoring unity between biotelemetry and bio-logging to enhance animal tracking research.
FACETS,
6, 260-265.
Author URL.
Özden Ö, Yıldırım S, Fuller WJ, Godley BJ (2021). Anthropogenic marine litter on the north coast of Cyprus: Insights into marine pollution in the eastern Mediterranean.
Marine Pollution Bulletin,
165Abstract:
Anthropogenic marine litter on the north coast of Cyprus: Insights into marine pollution in the eastern Mediterranean
The eastern Mediterranean is a region that has been relatively understudied with regards to anthropogenic marine litter despite potential for environmental and social costs. Here, coastal marine litter accumulation was assessed at eight beach locations along the coast of Northern Cyprus. Monthly surveys were performed between January 2017 and January 2019. All items ≥ 2.5 cm in diameter within the same 250 m2 plot were collected and processed. A total of 59,556 separate items were collected with a total mass of 697 kg. At the worst affected site (Ronnas Bay) litter accumulation averaged 1114 items and 11.9 kg per month. Plastic and polystyrene litter accounted for 82% (622.71 kg) of all litter types by mass and 96% (57,231) by frequency. Plastic bags, plastic pieces, drinks containers, caps/lids were the four most abundant forms of plastic by mass and by frequency. This suggests dumping/poor domestic waste governance as the main driver of marine litter in the region.
Abstract.
Blumenthal JM, Hardwick JL, Austin TJ, Broderick AC, Chin P, Collyer L, Ebanks-Petrie G, Grant L, Lamb LD, Olynik J, et al (2021). Cayman Islands Sea Turtle Nesting Population Increases over 22 Years of Monitoring.
Frontiers in Marine Science,
8Abstract:
Cayman Islands Sea Turtle Nesting Population Increases over 22 Years of Monitoring
Given differing trajectories of sea turtle populations worldwide, there is a need to assess and report long-term population trends and determine which conservation strategies are effective. In this study, we report on sea turtle nest monitoring in the Cayman Islands over a 22-year period. We found that green (Chelonia mydas) and loggerhead (Caretta caretta) nest numbers increased significantly across the three islands since monitoring began in 1998, but that hawksbill nest numbers remained low with a maximum of 13 nests recorded in a season. Comparing the first 5 years of nest numbers to the most recent 5 years, the greatest percentage increase in green turtle nests was in Grand Cayman from 82 to 1,005 nests (1,126%), whereas the greatest percentage increase for loggerhead turtle nests was in Little Cayman from 10 to 290 nests (3,800%). A captive breeding operation contributed to the increase in the Grand Cayman green turtle population, however, loggerhead turtles were never captive-bred, and these populations began to increase after a legal traditional turtle fishery became inactive in 2008. Although both species have shown significant signs of recovery, populations remain at a fragment of their historical level and are vulnerable to threats. Illegal harvesting occurs to this day, with multiple females taken from nesting beaches each year. For nests and hatchlings, threats include artificial lighting on nesting beaches, causing hatchlings to misorient away from the sea, and inundation of nests by seawater reducing hatch success. The impacts of lighting were found to increase over the monitoring period. Spatial data on nest distribution was used to identify critical nesting habitat for green and loggerhead turtles and is used by the Cayman Islands Department of Environment to facilitate remediation of threats related to beachside development and for targeted future management efforts.
Abstract.
Patrício AR, Hawkes LA, Monsinjon JR, Godley BJ, Fuentes MMPB (2021). Climate change and marine turtles: recent advances and future directions.
Endangered Species Research,
44, 363-395.
Abstract:
Climate change and marine turtles: recent advances and future directions
Climate change is a threat to marine turtles that is expected to affect all of their life stages. To guide future research, we conducted a review of the most recent literature on this topic, highlighting knowledge gains and research gaps since a similar previous review in 2009. Most research has been focussed on the terrestrial life history phase, where expected impacts will range from habitat loss and decreased reproductive success to feminization of populations, but changes in reproductive periodicity, shifts in latitudinal ranges, and changes in foraging success are all expected in the marine life history phase. Models have been proposed to improve estimates of primary sex ratios, while technological advances promise a better understanding of how climate can influence different life stages and habitats. We suggest a number of research priorities for an improved understanding of how climate change may impact marine turtles, including: improved estimates of primary sex ratios, assessments of the implications of female-biased sex ratios and reduced male production, assessments of the variability in upper thermal limits of clutches, models of beach sediment movement under sea level rise, and assessments of impacts on foraging grounds. Lastly, we suggest that it is not yet possible to recommend manipulating aspects of turtle nesting ecology, as the evidence base with which to understand the results of such interventions is not robust enough, but that strategies for mitigation of stressors should be helpful, providing they consider the synergistic effects of climate change and other anthropogenic-induced threats to marine turtles, and focus on increasing resilience.
Abstract.
Bersacola E, Parathian H, Frazão-Moreira A, Jaló M, Sanhá A, Regalla A, Saíd AR, Quecuta Q, Camará ST, Quade SMFF, et al (2021). Developing an Evidence-Based Coexistence Strategy to Promote Human and Wildlife Health in a Biodiverse Agroforest Landscape.
Frontiers in Conservation Science,
2Abstract:
Developing an Evidence-Based Coexistence Strategy to Promote Human and Wildlife Health in a Biodiverse Agroforest Landscape
Agroforest mosaics represent one of the most extensive human-impacted terrestrial systems worldwide and play an increasingly critical role in wildlife conservation. In such dynamic shared landscapes, coexistence can be compromised if people view wildlife as a source of infectious disease. A cross-disciplinary One Health knowledge base can help to identify evolving proponents and threats to sustainable coexistence and establish long-term project goals. Building on an existing knowledge base of human–wildlife interactions at Cantanhez National Park (NP), Guinea-Bissau, we developed a causal pathway Theory-of-Change approach in response to a newly identified disease threat of leprosy in the Critically Endangered western chimpanzee (Pan troglodytes verus). The goals of our project are to improve knowledge and surveillance of leprosy in humans and wildlife and increase capacity to manage human–wildlife interactions. We describe the core project activities that aim to (1) quantify space use by chimpanzees across Cantanhez NP and determine the distribution of leprosy in chimpanzees; (2) understand the health system and local perceptions of disease; and (3) identify fine-scale risk sites through participatory mapping of resources shared by humans and chimpanzees across target villages. We discuss the development of a biodiversity and health monitoring programme, an evidence-based One Health campaign, and a One Health environmental management plan that incorporates the sharing of space and resources, and the disease implications of human–non-human great ape interactions. We demonstrate the importance of multi-stakeholder engagement, and the development of strategy that fully considers interactions between people, wildlife, and the environment.
Abstract.
Rendell-Bhatti F, Paganos P, Pouch A, Mitchell C, D’Aniello S, Godley BJ, Pazdro K, Arnone MI, Jimenez-Guri E (2021). Developmental toxicity of plastic leachates on the sea urchin Paracentrotus lividus. Environmental Pollution, 269, 115744-115744.
Palmer JL, Beton D, Çiçek BA, Davey S, Duncan EM, Fuller WJ, Godley BJ, Haywood JC, Hüseyinoğlu MF, Omeyer LCM, et al (2021). Dietary analysis of two sympatric marine turtle species in the eastern Mediterranean.
Marine Biology,
168(6).
Abstract:
Dietary analysis of two sympatric marine turtle species in the eastern Mediterranean
AbstractDietary studies provide key insights into threats and changes within ecosystems and subsequent impacts on focal species. Diet is particularly challenging to study within marine environments and therefore is often poorly understood. Here, we examined the diet of stranded and bycaught loggerhead (Caretta caretta) and green turtles (Chelonia mydas) in North Cyprus (35.33° N, 33.47° E) between 2011 and 2019. A total of 129 taxa were recorded in the diet of loggerhead turtles (n = 45), which were predominantly carnivorous (on average 72.1% of dietary biomass), foraging on a large variety of invertebrates, macroalgae, seagrasses and bony fish in low frequencies. Despite this opportunistic foraging strategy, one species was particularly dominant, the sponge Chondrosia reniformis (21.5%). Consumption of this sponge decreased with increasing turtle size. A greater degree of herbivory was found in green turtles (n = 40) which predominantly consumed seagrasses and macroalgae (88.8%) with a total of 101 taxa recorded. The most dominant species was a Lessepsian invasive seagrass, Halophila stipulacea (31.1%). This is the highest percentage recorded for this species in green turtle diet in the Mediterranean thus far. With increasing turtle size, the percentage of seagrass consumed increased with a concomitant decrease in macroalgae. Seagrass was consumed year-round. Omnivory occurred in all green turtle size classes but reduced in larger turtles (> 75 cm CCL) suggesting a slow ontogenetic dietary shift. Macroplastic ingestion was more common in green (31.6% of individuals) than loggerhead turtles (5.7%). This study provides the most complete dietary list for marine turtles in the eastern Mediterranean.
Abstract.
Bates AE, Primack RB, Biggar BS, Bird TJ, Clinton ME, Command RJ, Richards C, Shellard M, Geraldi NR, Vergara V, et al (2021). Global COVID-19 lockdown highlights humans as both threats and custodians of the environment. Biological Conservation, 263, 109175-109175.
Omeyer LCM, Stokes KL, Beton D, Çiçek BA, Davey S, Fuller WJ, Godley BJ, Sherley RB, Snape RTE, Broderick AC, et al (2021). Investigating differences in population recovery rates of two sympatrically nesting sea turtle species. Animal Conservation, 24(5), 832-846.
Nelms SE, Alfaro-Shigueto J, Arnould JPY, Avila IC, Nash SB, Campbell E, Carter MID, Collins T, Currey RJC, Domit C, et al (2021). Marine mammal conservation: over the horizon.
Endangered Species Research,
44, 291-325.
Abstract:
Marine mammal conservation: over the horizon
Marine mammals can play important ecological roles in aquatic ecosystems, and their presence can be key to community structure and function. Consequently, marine mammals are often considered indicators of ecosystem health and flagship species. Yet, historical population declines caused by exploitation, and additional current threats, such as climate change, fisheries bycatch, pollution and maritime development, continue to impact many marine mammal species, and at least 25% are classified as threatened (Critically Endangered, Endangered or Vulnerable) on the IUCN Red List. Conversely, some species have experienced population increases/recoveries in recent decades, reflecting management interventions, and are heralded as conservation successes. To continue these successes and reverse the downward trajectories of at-risk species, it is necessary to evaluate the threats faced by marine mammals and the conservation mechanisms available to address them. Additionally, there is a need to identify evidence-based priorities of both research and conservation needs across a range of settings and taxa. To that effect we: (1) outline the key threats to marine mammals and their impacts, identify the associated knowledge gaps and recommend actions needed; (2) discuss the merits and downfalls of established and emerging conservation mechanisms; (3) outline the application of research and monitoring techniques; and (4) highlight particular taxa/populations that are in urgent need of focus.
Abstract.
Beton D, Broderick AC, Godley BJ, Kolaç E, Ok M, Snape RTE (2021). New monitoring confirms regular breeding of the Mediterranean monk seal in Northern Cyprus.
ORYX,
55(4), 522-525.
Abstract:
New monitoring confirms regular breeding of the Mediterranean monk seal in Northern Cyprus
The Endangered Mediterranean monk seal Monachus monachus is one of the most threatened marine mammals. Across Cyprus, suitable habitat and presence of monk seals is well documented and, recently, camera-trap surveys in Southern Cyprus found there to be pupping. We present results of the first camera-trap surveys in Northern Cyprus spanning the pupping period. Four adult/subadults and three pups were identified in three of eight caves monitored with camera traps. One site on the north-west of the island supported at least three adult/subadult seals and pupping occurred there in 3 consecutive years. The breeding and resting sites identified require urgent conservation to manage threats of disturbance, coastal development and fisheries bycatch. To determine the size of this population, a long-term survey with greater and more continuous coverage is required.
Abstract.
Nuno A, Matos L, Metcalfe K, Godley BJ, Broderick AC (2021). Perceived influence over marine conservation: Determinants and implications of empowerment.
Conservation Letters,
14(3).
Abstract:
Perceived influence over marine conservation: Determinants and implications of empowerment
Understanding empowerment is integral to facilitating sustainable use policies and requires assessing potential drivers. However, critical applications are rare in conservation. Using the island of Príncipe (São Tomé and Príncipe) as a case study, we undertook household surveys (N = 869) to assess potential drivers of psychological empowerment towards conservation, measured as the perceived abilities of people to individually or collectively influence marine conservation outcomes, accounting for gender. Law enforcement, collective influence, freedom of choice and action, environmental condition and living in coastal community were key variables for understanding perceived personal influence. In particular, no-fishing areas and raising awareness about sustainable practices were recommended by those with higher self-perceived influence. Such information on target groups and factors to promote is essential for facilitating empowerment towards conservation and laying robust foundations for resource comanagement, especially given the role communities can play in the face of limited state capacity and enforcement.
Abstract.
Duncan EM, Broderick AC, Critchell K, Galloway TS, Hamann M, Limpus CJ, Lindeque PK, Santillo D, Tucker AD, Whiting S, et al (2021). Plastic Pollution and Small Juvenile Marine Turtles: a Potential Evolutionary Trap.
FRONTIERS IN MARINE SCIENCE,
8 Author URL.
Jones JS, Porter A, Muñoz-Pérez JP, Alarcón-Ruales D, Galloway TS, Godley BJ, Santillo D, Vagg J, Lewis C (2021). Plastic contamination of a Galapagos Island (Ecuador) and the relative risks to native marine species.
Science of the Total Environment,
789Abstract:
Plastic contamination of a Galapagos Island (Ecuador) and the relative risks to native marine species
Ecuador's Galapagos Islands and their unique biodiversity are a global conservation priority. We explored the presence, composition and environmental drivers of plastic contamination across the marine ecosystem at an island scale, investigated uptake in marine invertebrates and designed a systematic priority scoring analysis to identify the most vulnerable vertebrate species. Beach contamination varied by site (macroplastic 0–0.66 items·m−2, microplastics 0–448.8 particles·m−2 or 0–74.6 particles·kg−1), with high plastic accumulation on east-facing beaches that are influenced by the Humboldt Current. Local littering and waste management leakages accounted for just 2% of macroplastic. Microplastics (including anthropogenic cellulosics) were ubiquitous but in low concentrations in benthic sediments (6.7–86.7 particles·kg−1) and surface seawater (0.04–0.89 particles·m−3), with elevated concentrations in the harbour suggesting some local input. Microplastics were present in all seven marine invertebrate species examined, found in 52% of individuals (n = 123) confirming uptake of microplastics in the Galapagos marine food web. Priority scoring analysis combining species distribution information, IUCN Red List conservation status and literature evidence of harm from entanglement and ingestion of plastics in similar species identified 27 marine vertebrates in need of urgent, targeted monitoring and mitigation including pinnipeds, seabirds, turtles and sharks.
Abstract.
Nelms SE, Duncan EM, Patel S, Badola R, Bhola S, Chakma S, Chowdhury GW, Godley BJ, Haque AB, Johnson JA, et al (2021). Riverine plastic pollution from fisheries: Insights from the Ganges River system. Science of the Total Environment, 756, 143305-143305.
Wilson DR, Godley BJ, Haggar GL, Santillo D, Sheen KL (2021). The influence of depositional environment on the abundance of microplastic pollution on beaches in the Bristol Channel, UK.
Mar Pollut Bull,
164Abstract:
The influence of depositional environment on the abundance of microplastic pollution on beaches in the Bristol Channel, UK.
Microplastic is a ubiquitous environmental contaminant, but large gaps still exist in our knowledge of its distribution. We conducted a detailed assessment of the extent and variability of microplastic pollution in the Bristol Channel, UK. Sand samples were collected between the 5th and 30th August 2017, with microplastic recovered from 15 of the 16 beaches sampled along a coastal extent of ~230 km. In total, 1446 particles of suspected microplastic were extracted using a cascade of sieves and visual identification. The most common microplastics recovered were fragments (74%) and industrial plastic pellets (13%). We used Fourier-Transform Infrared (FTIR) spectroscopy to analyse 25% of recovered particles, 96.5% of which were confirmed as plastic, with polyethylene (61%) and polypropylene (26%) the most common polymers. Our analysis of local beach environments indicates microplastic burdens were higher on lower energy beaches with finer sediments, highlighting the importance of depositional environment in determining microplastic abundance.
Abstract.
Author URL.
Doherty PD, Atsango BC, Ngassiki G, Ngouembe A, Bréheret N, Chauvet E, Godley BJ, Machin L, Moundzoho BD, Parnell RJ, et al (2021). Threats of illegal, unregulated, and unreported fishing to biodiversity and food security in the Republic of the Congo.
Conserv Biol,
35(5), 1463-1472.
Abstract:
Threats of illegal, unregulated, and unreported fishing to biodiversity and food security in the Republic of the Congo.
Illegal, unregulated, and unreported (IUU) fishing poses a major threat to effective management of marine resources, affecting biodiversity and communities dependent on these coastal resources. Spatiotemporal patterns of industrial fisheries in developing countries are often poorly understood, and global efforts to describe spatial patterns of fishing vessel activity are currently based on automatic identification system (AIS) data. However, AIS is often not a legal requirement on fishing vessels, likely resulting in underestimates of the scale and distribution of legal and illegal fishing activity, which could have significant ramifications for targeted enforcement efforts and the management of fisheries resources. To help address this knowledge gap, we analyzed 3 years of vessel monitoring system (VMS) data in partnership with the national fisheries department in the Republic of the Congo to describe the behavior of national and distant-water industrial fleets operating in these waters. We found that the spatial footprint of the industrial fisheries fleet encompassed over one-quarter of the Exclusive Economic Zone. On average, 73% of fishing activity took place on the continental shelf (waters shallower than 200 m). Our findings highlight that VMS is not acting as a deterrent or being effectively used as a proactive management tool. As much as 33% (13% on average) of fishing effort occurred in prohibited areas set aside to protect biodiversity, including artisanal fisheries resources, and the distant-water fleet responsible for as much as 84% of this illegal activity. Given the growth in industrial and distant-water fleets across the region, as well as low levels of management and enforcement, these findings highlight that there is an urgent need for the global community to help strengthen regional and national capacity to analyze national scale data sets if efforts to combat IUU fishing are to be effective.
Abstract.
Author URL.
March D, Metcalfe K, Tintoré J, Godley BJ (2021). Tracking the global reduction of marine traffic during the COVID-19 pandemic.
Nat Commun,
12(1).
Abstract:
Tracking the global reduction of marine traffic during the COVID-19 pandemic.
The COVID-19 pandemic has resulted in unparalleled global impacts on human mobility. In the ocean, ship-based activities are thought to have been impacted due to severe restrictions on human movements and changes in consumption. Here, we quantify and map global change in marine traffic during the first half of 2020. There were decreases in 70.2% of Exclusive Economic Zones but changes varied spatially and temporally in alignment with confinement measures. Global declines peaked in April, with a reduction in traffic occupancy of 1.4% and decreases found across 54.8% of the sampling units. Passenger vessels presented more marked and longer lasting decreases. A regional assessment in the Western Mediterranean Sea gave further insights regarding the pace of recovery and long-term changes. Our approach provides guidance for large-scale monitoring of the progress and potential effects of COVID-19 on vessel traffic that may subsequently influence the blue economy and ocean health.
Abstract.
Author URL.
Jimenez-Guri E, Roberts KE, García FC, Tourmente M, Longdon B, Godley BJ (2021). Transgenerational effects on development following microplastic exposure in Drosophila melanogaster.
PeerJ,
9Abstract:
Transgenerational effects on development following microplastic exposure in Drosophila melanogaster
Background. Plastic pollution affects all ecosystems, and detrimental effects to animals have been reported in a growing number of studies. However, there is a paucity of evidence for effects on terrestrial animals in comparison to those in the marine realm. Methods. We used the fly Drosophila melanogaster to study the effects that exposure to plastics may have on life history traits and immune response. We reared flies in four conditions: in media containing 1% virgin polyethylene, with no chemical additives; in media supplemented with 1% or 4% polyvinyl chloride, known to have a high content of added chemicals; and control flies in non-supplemented media. Plastic particle size ranged from 23–500 µm. We studied fly survival to viral infection, the length of the larval and pupal stage, sex ratios, fertility and the size of the resultant adult flies. We then performed crossings of F1 flies in non-supplemented media and looked at the life history traits of the F2. Results. Flies treated with plastics in the food media showed changes in fertility and sex ratio, but showed no differences in developmental times, adult size or the capacity to fight infections in comparison with controls. However, the offspring of treated flies reared in non-supplemented food had shorter life cycles, and those coming from both polyvinyl chloride treatments were smaller than those offspring of controls.
Abstract.
Cardiec F, Bertrand S, Witt MJ, Metcalfe K, Godley BJ, McClellan C, Vilela R, Parnell RJ, le Loc'h F (2020). "Too Big to Ignore": a feasibility analysis of detecting fishing events in Gabonese small-scale fisheries.
PLoS One,
15(6).
Abstract:
"Too Big to Ignore": a feasibility analysis of detecting fishing events in Gabonese small-scale fisheries.
In many developing countries, small-scale fisheries provide employment and important food security for local populations. To support resource management, the description of the spatiotemporal extent of fisheries is necessary, but often poorly understood due to the diffuse nature of effort, operated from numerous small wooden vessels. Here, in Gabon, Central Africa, we applied Hidden Markov Models to detect fishing patterns in seven different fisheries (with different gears) from GPS data. Models were compared to information collected by on-board observers (7 trips) and, at a larger scale, to a visual interpretation method (99 trips). Models utilizing different sampling resolutions of GPS acquisition were also tested. Model prediction accuracy was high with GPS data sampling rates up to three minutes apart. The minor loss of accuracy linked to model classification is largely compensated by the savings in time required for analysis, especially in a context of nations or organizations with limited resources. This method could be applied to larger datasets at a national or international scale to identify and more adequately manage fishing effort.
Abstract.
Author URL.
Jonsen ID, Patterson TA, Costa DP, Doherty PD, Godley BJ, Grecian WJ, Guinet C, Hoenner X, Kienle SS, Robison PW, et al (2020). A continuous-time state-space model for rapid quality-control of Argos. locations from animal-borne tags.
Movement Ecology,
8Abstract:
A continuous-time state-space model for rapid quality-control of Argos. locations from animal-borne tags
State-space models are important tools for quality control of error-prone
animal movement data. The near real-time (within 24 h) capability of the Argos
satellite system aids dynamic ocean management of human activities by informing
when animals enter intensive use zones. This capability also facilitates use of
ocean observations from animal-borne sensors in operational ocean forecasting
models. Such near real-time data provision requires rapid, reliable quality
control to deal with error-prone Argos locations. We formulate a
continuous-time state-space model for the three types of Argos location data
(Least-Squares, Kalman filter, and Kalman smoother), accounting for irregular
timing of observations. Our model is deliberately simple to ensure speed and
reliability for automated, near real-time quality control of Argos data. We
validate the model by fitting to Argos data collected from 61 individuals
across 7 marine vertebrates and compare model-estimated locations to GPS
locations. Estimation accuracy varied among species with median Root Mean
Squared Errors usually < 5 km and decreased with increasing data sampling rate
and precision of Argos locations. Including a model parameter to inflate Argos
error ellipse sizes resulted in more accurate location estimates. In some
cases, the model appreciably improved the accuracy of the Argos Kalman smoother
locations, which should not be possible if the smoother uses all available
information. Our model provides quality-controlled locations from Argos
Least-Squares or Kalman filter data with slightly better accuracy than Argos
Kalman smoother data that are only available via reprocessing. Simplicity and
ease of use make the model suitable both for automated quality control of near
real-time Argos data and for manual use by researchers working with historical
Argos data.
Abstract.
Bielli A, Alfaro-Shigueto J, Doherty PD, Godley BJ, Ortiz C, Pasara A, Wang JH, Mangel JC (2020). An illuminating idea to reduce bycatch in the Peruvian small-scale gillnet fishery. Biological Conservation, 241, 108277-108277.
Colman LP, Lara PH, Bennie J, Broderick AC, de Freitas JR, Marcondes A, Witt MJ, Godley BJ (2020). Assessing coastal artificial light and potential exposure of wildlife at a national scale: the case of marine turtles in Brazil.
Biodiversity and Conservation,
29(4), 1135-1152.
Abstract:
Assessing coastal artificial light and potential exposure of wildlife at a national scale: the case of marine turtles in Brazil
AbstractCoastal areas provide critical nesting habitat for marine turtles. Understanding how artificial light might impact populations is key to guide management strategies. Here we assess the extent to which nesting populations of four marine turtle species—leatherback (Dermochelys coriacea), olive ridley (Lepidochelys olivacea), hawksbill (Eretmochelys imbricata) and two subpopulations of loggerhead (Caretta caretta) turtles—are exposed to light pollution across 604 km of the Brazilian coast. We used yearly night-time satellite images from two 5-year periods (1992–1996 and 2008–2012) from the US Air Force Defense Meteorological Satellite Programme (DMSP) to determine the proportion of nesting areas that are exposed to detectable levels of artificial light and identify how this has changed over time. Over the monitored time-frame, 63.7% of the nesting beaches experienced an increase in night light levels. Based on nest densities, we identified 54 reproductive hotspots: 62.9% were located in areas potentially exposed to light pollution. Light levels appeared to have a significant effect on nest densities of hawksbills and the northern loggerhead turtle stock, however high nest densities were also seen in lit areas. The status of all species/subpopulations has improved across the time period despite increased light levels. These findings suggest that (1) nest site selection is likely primarily determined by variables other than light and (2) conservation strategies in Brazil appear to have been successful in contributing to reducing impacts on nesting beaches. There is, however, the possibility that light also affects hatchlings in coastal waters, and impacts on population recruitment may take longer to fully manifest in nesting numbers. Recommendations are made to further this work to provide deeper insights into the impacts of anthropogenic light on marine turtles.
Abstract.
Omeyer LCM, Doherty PD, Dolman S, Enever R, Reese A, Tregenza N, Williams R, Godley BJ (2020). Assessing the Effects of Banana Pingers as a Bycatch Mitigation Device for Harbour Porpoises (Phocoena phocoena). Frontiers in Marine Science, 7
Campbell E, Mangel J, Alfaro-Shigueto J, Mena JL, Thurstan R, Godley B (2020). Coexisting in the Peruvian Amazon: Interactions between fisheries and river dolphins. Journal for Nature Conservation
Ikaran M, Agamboué PD, Scholtz O, Braet Y, Godley BJ, Marco A (2020). Cryptic massive nest colonisation by ants and termites in the world's largest leatherback turtle rookery. Ethology Ecology & Evolution, 32(3), 264-281.
Sutherland WJ, Alvarez‐Castañeda ST, Amano T, Ambrosini R, Atkinson P, Baxter JM, Bond AL, Boon PJ, Buchanan KL, Barlow J, et al (2020). Ensuring tests of conservation interventions build on existing literature. Conservation Biology, 34(4), 781-783.
Gough CLA, Dewar KM, Godley BJ, Zafindranosy E, Broderick AC (2020). Evidence of Overfishing in Small-Scale Fisheries in Madagascar. Frontiers in Marine Science, 7
Edwards RC, Godley BJ, Nuno A (2020). Exploring connections among the multiple outputs and outcomes emerging from 25 years of sea turtle conservation in Northern Cyprus. Journal for Nature Conservation, 55, 125816-125816.
Haywood JC, Casale P, Freggi D, Fuller WJ, Godley BJ, Lazar B, Margaritoulis D, Rees AF, Shutler JD, Snape RT, et al (2020). Foraging ecology of Mediterranean juvenile loggerhead turtles: insights from C and N stable isotope ratios.
Marine Biology,
167(3).
Abstract:
Foraging ecology of Mediterranean juvenile loggerhead turtles: insights from C and N stable isotope ratios
AbstractBycatch is one of the key threats to juvenile marine turtles in the Mediterranean Sea. As fishing methods are regional or habitat specific, the susceptibility of marine turtles may differ according to inter- and intra-population variations in foraging ecology. An understanding of these variations is necessary to assess bycatch susceptibility and to implement region-specific management. To determine if foraging ecology differs with region, sex, and size of juvenile loggerhead turtles (Caretta caretta), stable isotope analysis of carbon and nitrogen was performed on 171 juveniles from a range of foraging regions across the central and eastern Mediterranean Sea. Isotope ratios differed with geographical region, likely due to baseline variations in δ13C and δ15N values. The absence of sex-specific differences suggests that within an area, all comparably sized animals likely exploit similar foraging strategies, and therefore, their susceptibility to fisheries threats will likely be similar. The isotope ratios of juveniles occupying the North East Adriatic and North Levantine basin increased with size, potentially due to increased consumption of more prey items at higher trophic levels from a more neritic source. Isotope ratios of juveniles with access to both neritic and oceanic habitats did not differ with size which is consistent with them consuming prey items from both habitats interchangeably. With foraging habitats exploited differently among size classes in a population, the susceptibility to fisheries interactions will likely differ with size; therefore, region-specific management approaches will be needed.
Abstract.
Parton KJ, Godley BJ, Santillo D, Tausif M, Omeyer LCM, Galloway TS (2020). Investigating the presence of microplastics in demersal sharks of the North-East Atlantic.
Sci Rep,
10(1).
Abstract:
Investigating the presence of microplastics in demersal sharks of the North-East Atlantic.
Microplastic pollution is ubiquitous in the marine environment and is ingested by numerous marine species. Sharks are an understudied group regarding their susceptibility to microplastic ingestion. Here, we provide evidence of ingestion of microplastic and other anthropogenic fibres in four demersal sharks species found in the waters of the United Kingdom and investigate whether body burdens of contamination vary according to species, sex or size. Sharks were collected from the North-East Atlantic. Stomachs and digestive tracts of 46 sharks of 4 species were examined and 67% of samples contained at least one contaminant particle. Although we acknowledge modest sample size, estimated particle burden increased with body size but did not vary systematically with sex or species. A total of 379 particles were identified, leading to median estimates ranging from 2 to 7.5 ingested contaminants per animal for the 4 species. The majority were fibrous in nature (95%) and blue (88%) or black (9%) in colour. A subsample of contaminants (N = 62) were subject to FT-IR spectroscopy and polymers identified as: synthetic cellulose (33.3%), polypropylene (25%), polyacrylamides (10%) and polyester (8.3%). The level of risk posed to shark species by this level of contamination is unknown. Nevertheless, this study presents the first empirical evidence and an important baseline for ingestion of microplastics and other anthropogenic fibres in native UK shark species and highlights the pervasive nature of these pollutants.
Abstract.
Author URL.
Botterell Z, Penrose R, Witt M, Godley B (2020). Long-term insights into marine turtle sightings, strandings and captures around the UK and Ireland (1910-2018). The Journal of the Marine Biological Association of the United Kingdom
Godley BJ, Broderick AC, Colman LP, Formia A, Godfrey MH, Hamann M, Nuno A, Omeyer LCM, Patrício AR, Phillott AD, et al (2020). Reflections on sea turtle conservation. Oryx, 54(3), 287-289.
Bielli A, Alfaro-Shigueto J, Doherty PD, Godley BJ, Wang JH, Mangel JC (2020). Response to “Design issues adumbrate conclusions on LED-mediated bycatch risk reduction of cetaceans and turtles in fishing nets: a comment on Bielli et al. (2020)”. Biological Conservation, 243
Doherty PD, Broderick AC, Godley BJ, Hart KA, Phillips Q, Sanghera A, Stringell TB, Walker JT, Richardson PB (2020). Spatial Ecology of Sub-Adult Green Turtles in Coastal Waters of the Turks and Caicos Islands: Implications for Conservation Management. Frontiers in Marine Science, 7
Lieber L, Hall G, Hall J, Berrow S, Johnston E, Gubili C, Sarginson J, Francis M, Duffy C, Wintner SP, et al (2020). Spatio-temporal genetic tagging of a cosmopolitan planktivorous shark provides insight to gene flow, temporal variation and site-specific re-encounters.
Scientific Reports,
10(1).
Abstract:
Spatio-temporal genetic tagging of a cosmopolitan planktivorous shark provides insight to gene flow, temporal variation and site-specific re-encounters
AbstractMigratory movements in response to seasonal resources often influence population structure and dynamics. Yet in mobile marine predators, population genetic consequences of such repetitious behaviour remain inaccessible without comprehensive sampling strategies. Temporal genetic sampling of seasonally recurring aggregations of planktivorous basking sharks, Cetorhinus maximus, in the Northeast Atlantic (NEA) affords an opportunity to resolve individual re-encounters at key sites with population connectivity and patterns of relatedness. Genetic tagging (19 microsatellites) revealed 18% of re-sampled individuals in the NEA demonstrated inter/multi-annual site-specific re-encounters. High genetic connectivity and migration between aggregation sites indicate the Irish Sea as an important movement corridor, with a contemporary effective population estimate (Ne) of 382 (CI = 241–830). We contrast the prevailing view of high gene flow across oceanic regions with evidence of population structure within the NEA, with early-season sharks off southwest Ireland possibly representing genetically distinct migrants. Finally, we found basking sharks surfacing together in the NEA are on average more related than expected by chance, suggesting a genetic consequence of, or a potential mechanism maintaining, site-specific re-encounters. Long-term temporal genetic monitoring is paramount in determining future viability of cosmopolitan marine species, identifying genetic units for conservation management, and for understanding aggregation structure and dynamics.
Abstract.
CARR P, VOTIER S, KOLDEWEY H, GODLEY B, WOOD H, NICOLL MAC (2020). Status and phenology of breeding seabirds and a review of Important Bird and Biodiversity Areas in the British Indian Ocean Territory.
Bird Conservation International,
31(1), 14-34.
Abstract:
Status and phenology of breeding seabirds and a review of Important Bird and Biodiversity Areas in the British Indian Ocean Territory
SummarySeabirds are one of the most threatened avian taxa and are hence a high conservation priority. Managing seabirds is challenging, requiring conservation actions at sea (e.g. Marine Protected Areas - MPAs) and on land (e.g. protection of breeding sites). Important Bird and Biodiversity Areas (IBAs) have been successfully used to identify sites of global importance for the conservation of bird populations, including breeding seabirds. The challenge of identifying suitable IBAs for tropical seabirds is exacerbated by high levels of dispersal, aseasonal and asynchronous breeding. The western Indian Ocean supports ~19 million breeding seabirds of 30 species, making it one of the most significant tropical seabird assemblages in the world. Within this is the British Indian Ocean Territory (BIOT), encompassing 55 islands of the Chagos Archipelago, which supports 18 species of breeding seabird and one of the world’s largest no-take MPAs. Between January and March in 1975 and 1996, eight and 45 islands respectively were surveyed for seabirds and the data used to designate 10 islands as IBAs. A further two were proposed following an expedition to 26 islands in February/March 2006. Due to the historic and restricted temporal and spatial nature of these surveys, the current IBA recommendations may not accurately represent the archipelago’s present seabird status and distribution. To update estimates of the BIOT breeding seabird assemblage and reassess the current IBA recommendations, we used seabird census data collected in every month except September from every island, gathered during 2008–2018. The maximum number of breeding seabirds for a nominal year was 281,596 pairs of 18 species, with three species making up 96%: Sooty Tern Onychoprion fuscatus - 70%, Lesser Noddy Anous tenuirostris - 18% and Red-footed Booby Sula sula - 8%. Phenology was a complex species-specific mix of synchronous and asynchronous breeding, as well as seasonal and aseasonal breeding. Nine of the 10 designated IBAs and the two proposed IBAs qualified for IBA status based on breeding seabirds. However, not every IBA qualified each year because Sooty Terns periodically abandoned breeding islands and Tropical Shearwater Puffinus bailloni breeding numbers dropped below IBA qualifying criteria in some years. Further, one survey per year does not always capture the periodic breeding of some tropical seabirds. We propose therefore, that IBAs in BIOT are better designated at the island cluster level rather than by specific island and require two surveys six months apart per year. This work highlights the merits of long-term, systematic, versus incidental surveys for breeding tropical seabirds and the subsequent associated designation of IBAs.
Abstract.
Metcalfe K, Bréheret N, Bal G, Chauvet E, Doherty PD, Formia A, Girard A, Mavoungou J-G, Parnell RJ, Pikesley SK, et al (2020). Tracking foraging green turtles in the Republic of the Congo: insights into spatial ecology from a data poor region.
Oryx,
54(3), 299-306.
Abstract:
Tracking foraging green turtles in the Republic of the Congo: insights into spatial ecology from a data poor region
AbstractGlobally, marine turtles are considered threatened throughout their range, and therefore conservation practitioners are increasingly investing resources in marine protected areas to protect key life history stages and critical habitats, including foraging grounds, nesting beaches and inter-nesting areas. Empirical data on the distribution of these habitats and/or the spatial ecology and behaviour of individuals of many marine turtle populations are often lacking, undermining conservation efforts, particularly along the Atlantic coast of Africa. Here we contribute to the knowledge base in this region by describing patterns of habitat use for nine green turtles Chelonia mydas tagged with satellite platform transmitter terminals at a foraging ground in Loango Bay, Republic of the Congo, one of only a few documented mainland foraging grounds for marine turtles in Central Africa. Analyses of these data revealed that core areas of habitat use and occupancy for a wide range of size/age classes were restricted to shallow waters adjacent to Pointe Indienne in Loango Bay, with most individuals showing periods of high fidelity to this area. These data are timely given the Congolese government recently announced its intention to create a marine conservation zone to protect marine turtles in Loango Bay. Despite the small sample size of this study, these data exemplify the need for comprehensive strategies that span national jurisdictions, as we provide the first documented evidence of linkages between green turtle foraging sites in Central Africa (Loango Bay, Republic of the Congo) and Southern Africa (Mussulo Bay, Angola).
Abstract.
Senko JF, Nelms SE, Reavis JL, Witherington B, Godley BJ, Wallace BP (2020). Understanding individual and population-level effects of plastic pollution on marine megafauna.
Endangered Species Research,
43, 234-252.
Abstract:
Understanding individual and population-level effects of plastic pollution on marine megafauna
Plastic pollution is increasing rapidly throughout the world’s oceans and is considered a major threat to marine wildlife and ecosystems. Although known to cause lethal or sub-lethal effects to vulnerable marine megafauna, population-level impacts of plastic pollution have not been thoroughly investigated. Here, we compiled and evaluated information from peer-reviewed studies that reported deleterious individual-level effects of plastic pollution on air-breathing marine megafauna (i.e. seabirds, marine mammals, and sea turtles) worldwide, highlighting those that assessed potential population-level effects. Lethal and sub-lethal individual-level effects included drowning, starvation, gastrointestinal tract damage, malnutrition, physical injury, reduced mobility, and physiological stress, resulting in reduced energy acquisition and assimilation, compromised health, reproductive impairment, and mortality. We found 47 studies published between 1969 and 2020 that considered population-level effects of plastic entanglement (n = 26), ingestion (n = 19), or both (n = 2). of these, 7 inferred population-level effects (n = 6, entanglement; n = 1, ingestion), whereas 19 lacked evidence for effects (n = 12, entanglement; n = 6, ingestion; n = 1, both). However, no study in the past 50 yr reported direct evidence of population-level effects. Despite increased interest in and awareness of the presence of plastic pollution throughout the world’s oceans, the extent and magnitude of demographic impacts on marine megafauna remains largely unassessed and therefore unknown, in contrast to well-documented effects on individuals. Addressing this major assessment gap will allow researchers and managers to compare relative effects of multiple threats—including plastic pollution—on marine megafauna populations, thus providing appropriate context for strategic conservation priority-setting.
Abstract.
Cerritelli G, Bianco G, Santini G, Broderick AC, Godley BJ, Hays GC, Luschi P, Åkesson S (2019). Assessing reliance on vector navigation in the long-distance oceanic migrations of green sea turtles.
Behavioral Ecology,
30(1), 68-79.
Abstract:
Assessing reliance on vector navigation in the long-distance oceanic migrations of green sea turtles
Vector navigation, i.e. maintaining a constant heading for a given amount of time, is hypothesized to provide a viable basis for the navigational feats of a number of long-distance animal migrants. Since animals following this strategy are subject to drift by wind or by ocean current, performing long migrations relying on vector navigation is particularly challenging. We tested whether vector navigation could be involved in the migrations of green turtles (Chelonia mydas) that migrate between the remote Ascension Island and Brazil. To this aim, a novel approach was followed using individual-based numerical models to simulate migratory trajectories of virtual turtles that were compared to actual routes reconstructed by satellite. Simulated postnesting migrations from Ascension revealed that weak currents enabled modeled turtles to reach the Brazilian coast, but only for a limited range of headings around due West. This conclusion was corroborated by comparing modeled trajectories with the actual routes of previously tracked turtles, with a beeline vector navigation strategy providing the best fit, although a true-navigation strategy directed to the landfall site produced similar results. Finally, we tested if a vector navigational strategy was feasible for the prebreeding migration from Brazil towards Ascension, but modeled routes mostly failed to reach the island or a larger area around it, with individuals drifting away under the influence of currents. We conclude that Ascension turtles can take advantage of vector navigation when migrating towards a wide target like the Brazilian coast, while the demanding prebreeding migration likely requires more complex navigational systems.
Abstract.
Godley B (2019). Companion interview. BSAVA Companion, 2019(6), 28-29.
Elliott BW, Read AJ, Godley BJ, Nelms SE, Nowacek DP (2019). Critical information gaps remain in understanding impacts of industrial seismic surveys on marine vertebrates.
Endangered Species Research,
39, 247-254.
Abstract:
Critical information gaps remain in understanding impacts of industrial seismic surveys on marine vertebrates
Anthropogenic noise is increasing throughout the world's oceans. One major contributor is industrial seismic surveys-a process typically undertaken to locate and estimate the quantity of oil and gas deposits beneath the seafloor-which, in recent years, has increased in magnitude and scope in some regions. Regulators permit this activity despite widespread uncertainties regarding the potential ecological impacts of seismic surveys and gaps in baseline information on some key species of conservation concern. Research to date suggests that impacts vary, from displacement to direct mortality, but these effects remain poorly understood for most species. Here, we summarize potential effects of seismic surveys, describe key knowledge gaps, and recommend broad-scale research priorities for 3 impacted taxonomic groups: fish, marine mammals, and sea turtles. We also suggest further technological advances, improved mitigation measures, and better policy and management structures to minimize the ecological impacts of seismic surveys in light of scientific uncertainty.
Abstract.
Bellini C, Santos AJB, Patrício AR, Bortolon LFW, Godley BJ, Marcovaldi MA, Tilley D, Colman LP (2019). Distribution and growth rates of immature hawksbill turtles Eretmochelys imbricata in Fernando de Noronha, Brazil. Endangered Species Research, 40, 41-52.
Barbanti A, Turmo M, Blumenthal J, Boyle J, Broderick A, Collyer L, Ebanks-Petrie G, Godley B, Pascual M, Carreras C, et al (2019). Founding in action: genetic assessment of new populations from the same reintroduction program. Frontiers in Marine Science, 6
Haywood J, Fuller W, Godley B, Shutler J, Widdicombe S, Broderick A (2019). Global review and inventory: how stable isotopes are helping us understand ecology and inform conservation of marine turtles. Marine Ecology Progress Series, 613, 217-245.
Barbanti A, Martin C, Blumenthal JM, Boyle J, Broderick AC, Collyer L, Ebanks-Petrie G, Godley BJ, Mustin W, Ordóñez V, et al (2019). How many came home? Evaluating ex situ conservation of green turtles in the Cayman Islands.
Mol Ecol,
28(7), 1637-1651.
Abstract:
How many came home? Evaluating ex situ conservation of green turtles in the Cayman Islands.
Ex situ management is an important conservation tool that allows the preservation of biological diversity outside natural habitats while supporting survival in the wild. Captive breeding followed by re-introduction is a possible approach for endangered species conservation and preservation of genetic variability. The Cayman Turtle Centre Ltd was established in 1968 to market green turtle (Chelonia mydas) meat and other products and replenish wild populations, thought to be locally extirpated, through captive breeding. We evaluated the effects of this re-introduction programmme using molecular markers (13 microsatellites, 800-bp D-loop and simple tandem repeat mitochondrial DNA sequences) from captive breeders (N = 257) and wild nesting females (N = 57) (sampling period: 2013-2015). We divided the captive breeders into three groups: founders (from the original stock), and then two subdivisions of F1 individuals corresponding to two different management strategies, cohort 1995 ("C1995") and multicohort F1 ("MCF1"). Loss of genetic variability and increased relatedness was observed in the captive stock over time. We found no significant differences in diversity among captive and wild groups, and similar or higher levels of haplotype variability when compared to other natural populations. Using parentage and sibship assignment, we determined that 90% of the wild individuals were related to the captive stock. Our results suggest a strong impact of the re-introduction programmme on the present recovery of the wild green turtle population nesting in the Cayman Islands. Moreover, genetic relatedness analyses of captive populations are necessary to improve future management actions to maintain genetic diversity in the long term and avoid inbreeding depression.
Abstract.
Author URL.
Duncan EM, Broderick AC, Fuller WJ, Galloway TS, Godfrey MH, Hamann M, Limpus CJ, Lindeque PK, Mayes AG, Omeyer LCM, et al (2019). Microplastic ingestion ubiquitous in marine turtles.
Glob Chang Biol,
25(2), 744-752.
Abstract:
Microplastic ingestion ubiquitous in marine turtles.
Despite concerns regarding the environmental impacts of microplastics, knowledge of the incidence and levels of synthetic particles in large marine vertebrates is lacking. Here, we utilize an optimized enzymatic digestion methodology, previously developed for zooplankton, to explore whether synthetic particles could be isolated from marine turtle ingesta. We report the presence of synthetic particles in every turtle subjected to investigation (n = 102) which included individuals from all seven species of marine turtle, sampled from three ocean basins (Atlantic [ATL]: n = 30, four species; Mediterranean (MED): n = 56, two species; Pacific (PAC): n = 16, five species). Most particles (n = 811) were fibres (ATL: 77.1% MED: 85.3% PAC: 64.8%) with blue and black being the dominant colours. In lesser quantities were fragments (ATL: 22.9%: MED: 14.7% PAC: 20.2%) and microbeads (4.8%; PAC only; to our knowledge the first isolation of microbeads from marine megavertebrates). Fourier transform infrared spectroscopy (FT-IR) of a subsample of particles (n = 169) showed a range of synthetic materials such as elastomers (MED: 61.2%; PAC: 3.4%), thermoplastics (ATL: 36.8%: MED: 20.7% PAC: 27.7%) and synthetic regenerated cellulosic fibres (SRCF; ATL: 63.2%: MED: 5.8% PAC: 68.9%). Synthetic particles being isolated from species occupying different trophic levels suggest the possibility of multiple ingestion pathways. These include exposure from polluted seawater and sediments and/or additional trophic transfer from contaminated prey/forage items. We assess the likelihood that microplastic ingestion presents a significant conservation problem at current levels compared to other anthropogenic threats.
Abstract.
Author URL.
Nelms SE, Barnett J, Brownlow A, Davison NJ, Deaville R, Galloway TS, Lindeque PK, Santillo D, Godley BJ (2019). Microplastics in marine mammals stranded around the British coast: ubiquitous but transitory?.
Scientific Reports,
9(1).
Abstract:
Microplastics in marine mammals stranded around the British coast: ubiquitous but transitory?
Plastic pollution represents a pervasive and increasing threat to marine ecosystems worldwide and there is a need to better understand the extent to which microplastics (
Abstract.
Tilley D, Ball S, Ellick J, Godley BJ, Weber N, Weber SB, Broderick AC (2019). No evidence of fine scale thermal adaptation in green turtles.
Journal of Experimental Marine Biology and Ecology,
514-515, 110-117.
Abstract:
No evidence of fine scale thermal adaptation in green turtles
Adaptation to increasing temperatures may enable species to mitigate the long-term impacts of climate change. Sea turtles have temperature dependent sex determination (TSD) and variation in the thermal reaction norm, which influences offspring sex ratio, has been suggested as a potential adaptive mechanism to rising global temperatures. Here, we investigate the sex ratio of green turtle Chelonia mydas offspring from nests on beaches with notable differences in their thermal properties, to look for evidence of localised adaptation. We compared pivotal temperatures and hatch success in both the laboratory and in situ using eggs laid on two nesting beaches (dark vs. pale sand) at Ascension Island that represent the extremes of the range of incubation temperatures experienced by this population. We found no effect of beach of origin on pivotal temperatures, hatch success, or hatchling size in the laboratory or the wild. This suggests that turtles from the same rookery are not locally adapted to different thermal conditions experienced during incubation. Under predicted climate change scenarios, this will result in reduced hatch success and an increased proportion of female offspring unless temporal or spatial range shifts occur.
Abstract.
Clay TA, Alfaro-Shigueto J, Godley BJ, Tregenza N, Mangel JC (2019). Pingers reduce the activity of Burmeister's porpoise around small-scale gillnet vessels.
Marine Ecology Progress Series,
626, 197-208.
Abstract:
Pingers reduce the activity of Burmeister's porpoise around small-scale gillnet vessels
Incidental mortality (bycatch) in gillnet fisheries is a major threat to many cetacean populations. Acoustic alarms or pingers are a widely adopted management tool used to deter dolphins and porpoises from nets; however, their efficacy is largely species- and fishery-dependent. As such, results from experimental trials may have limited transferability to poorly studied species or fisheries. Here, we investigated the effect of pingers on the behaviour of Burmeister's porpoise Phocoena spinipinnis in the vicinity of the Peruvian small-scale driftnet fleet. Over a 4 yr period (2009-2012), 116 control (without pingers) and 94 experimental (with pingers) fishing sets were observed, and porpoise acoustic activity around nets was recorded using passive acoustic loggers (C-PODs). We modelled variation in detection rates as a function of pinger use and habitat covariates, and found that in regions of preferred habitat associated with cooler (17-18°C), shallow waters (within the 100 m isobath), the use of pingers lead to an 86% reduction in porpoise activity around nets. Our results suggest that pingers are likely to be particularly effective at deterring Burmeister's porpoises from fishing nets, and given the vast capacity of this and other fleets in the region, may substantially reduce mortality. This study also emphasizes the potential of passive acoustic monitoring to determine the effectiveness of bycatch mitigation measures, both for species for which visual observations are scarce, and also in regions where gathering statistically meaningful bycatch rates is logistically challenging.
Abstract.
Omeyer LCM, Broderick AC, Godley BJ, Snape RTE, Fuller WJ (2019). The effect of biologging systems on reproduction, growth and survival of adult sea turtles.
Movement Ecology,
7(2), 1-12.
Abstract:
The effect of biologging systems on reproduction, growth and survival of adult sea turtles
Background:. Telemetry and biologging systems, ‘tracking’ hereafter, have been instrumental in meeting the challenges associated with studying the ecology and behaviour of cryptic, wide-ranging marine mega-vertebrates. Over recent decades, globally, sea turtle tracking has increased exponentially, across species and life-stages, despite a paucity of studies investigating the effects of such devices on study animals. Indeed, such studies are key to informing whether data collected are unbiased and, whether derived estimates can be considered typical of the population at large.
Methods:. Here, using a 26-year individual-based monitoring dataset on sympatric green (Chelonia mydas) and loggerhead (Caretta caretta) turtles, we provide the first analysis of the effects of device attachment on reproduction, growth and survival of nesting females.
Results:. We found no significant difference in growth and reproductive correlates between tracked and non-tracked females in the years following device attachment. Similarly, when comparing pre- and post-tracking data, we found no significant difference in the reproductive correlates of tracked females for either species or significant carry-over effects of device attachment on reproductive correlates in green turtles. The latter was not investigated for loggerhead turtles due to small sample size. Finally, we found no significant effects of device attachment on return rates or survival of tracked females for either species.
Conclusion:. While there were no significant detrimental effects of device attachment on adult sea turtles in this region, our study highlights the need for other similar studies elsewhere and the value of long-term individual-based monitoring.
Abstract.
Dunn DC, Harrison A-L, Curtice C, DeLand S, Donnelly B, Fujioka E, Heywood E, Kot CY, Poulin S, Whitten M, et al (2019). The importance of migratory connectivity for global ocean policy.
Proceedings of the Royal Society B: Biological Sciences,
286(1911), 20191472-20191472.
Abstract:
The importance of migratory connectivity for global ocean policy
The distributions of migratory species in the ocean span local, national and international jurisdictions. Across these ecologically interconnected regions, migratory marine species interact with anthropogenic stressors throughout their lives. Migratory connectivity, the geographical linking of individuals and populations throughout their migratory cycles, influences how spatial and temporal dynamics of stressors affect migratory animals and scale up to influence population abundance, distribution and species persistence. Population declines of many migratory marine species have led to calls for connectivity knowledge, especially insights from animal tracking studies, to be more systematically and synthetically incorporated into decision-making. Inclusion of migratory connectivity in the design of conservation and management measures is critical to ensure they are appropriate for the level of risk associated with various degrees of connectivity. Three mechanisms exist to incorporate migratory connectivity into international marine policy which guides conservation implementation: site-selection criteria, network design criteria and policy recommendations. Here, we review the concept of migratory connectivity and its use in international policy, and describe the Migratory Connectivity in the Ocean system, a migratory connectivity evidence-base for the ocean. We propose that without such collaboration focused on migratory connectivity, efforts to effectively conserve these critical species across jurisdictions will have limited effect.
Abstract.
Omeyer LCM, Casale P, Fuller WJ, Godley BJ, Holmes KE, Snape RTE, Broderick AC (2019). The importance of passive integrated transponder (PIT) tags for measuring life-history traits of sea turtles. Biological Conservation, 240, 108248-108248.
Colman LP, Thomé JCA, Almeida ADP, Baptistotte C, Paulo PC, Broderick AC, Ribeiro FA, Vila-Verde L, Godley BJ (2019). Thirty years of leatherback turtle Dermochelys coriacea nesting in Espírito Santo, Brazil, 1988-2017: Reproductive biology and conservation.
Endangered Species Research,
39, 147-158.
Abstract:
Thirty years of leatherback turtle Dermochelys coriacea nesting in Espírito Santo, Brazil, 1988-2017: Reproductive biology and conservation
In the southwestern Atlantic Ocean, leatherback turtles Dermochelys coriacea are only known to regularly nest in eastern Brazil, on the coast of the state of Espírito Santo. Here, we present an analysis of the nesting ecology, population trends and conservation status of this leather - back turtle colony between 1988 and 2017. We observed an increasing, although variable, trend in the annual number of nests, with the mean increasing from 25.6 nests in the first 5 yr of the study to 89.8 in the last 5 yr. Concurrently, there was also a significant decrease in the mean curved carapace length of the population, which we hypothesize was caused by recruitment of new females to the nesting population. Throughout the study period, nests were concentrated in the southern part of the 160 km long study area. No change was observed in the annual median nesting date. Mean annual hatching success was 66.0% and no significant variation in hatching success was detected after a major spill of mining tailings into the nesting area in 2015. We postulate that local conservation actions that started in the 1980s have contributed to the gentle recovery of this population; however, given the small population size and restricted nesting geographical distribution alongside the persistence of various threats-fisheries bycatch, climate change, pollution and coastal development-this population continues to be of conservation concern.
Abstract.
March D, Boehme L, Tintoré J, Vélez‐Belchi PJ, Godley BJ (2019). Towards the integration of animal‐borne instruments into global ocean observing systems. Global Change Biology, 26(2), 586-596.
Rees AF, Papathanasopoulou N, Godley BJ (2019). Tracking Hawksbills in Kuwait: Contributions to Regional Behavioral Insights.
Chelonian Conservation and Biology,
18(1), 86-90.
Abstract:
Tracking Hawksbills in Kuwait: Contributions to Regional Behavioral Insights
Hawksbill turtles from nesting areas in the south of the Arabian/Persian Gulf have been shown to migrate to numerous individual foraging sites across the region and undertake "summer migration loops" (SMLs) to avoid the most extreme sea temperatures. We tracked hawksbills nesting in Kuwait (n = 4) that migrated to hitherto undescribed foraging sites but showed no evidence of SMLs despite experiencing water temperatures greater than 33°C. Increasing the sample size for Kuwait turtles, tracking males, and publishing results from other important hawksbill nesting areas in Saudi Arabia are recommended to get a fuller indication of potential behavioral plasticity in the region.
Abstract.
Hays GC, Bailey H, Bograd SJ, Bowen WD, Campagna C, Carmichael RH, Casale P, Chiaradia A, Costa DP, Cuevas E, et al (2019). Translating Marine Animal Tracking Data into Conservation Policy and Management.
Trends in Ecology and Evolution,
34(5), 459-473.
Abstract:
Translating Marine Animal Tracking Data into Conservation Policy and Management
© 2019 Elsevier Ltd There have been efforts around the globe to track individuals of many marine species and assess their movements and distribution, with the putative goal of supporting their conservation and management. Determining whether, and how, tracking data have been successfully applied to address real-world conservation issues is, however, difficult. Here, we compile a broad range of case studies from diverse marine taxa to show how tracking data have helped inform conservation policy and management, including reductions in fisheries bycatch and vessel strikes, and the design and administration of marine protected areas and important habitats. Using these examples, we highlight pathways through which the past and future investment in collecting animal tracking data might be better used to achieve tangible conservation benefits.
Abstract.
Trew BT, Grantham HS, Barrientos C, Collins T, Doherty PD, Formia A, Godley BJ, Maxwell SM, Parnell RJ, Pikesley SK, et al (2019). Using Cumulative Impact Mapping to Prioritize Marine Conservation Efforts in Equatorial Guinea. Frontiers in Marine Science, 6
Nelms SE, Parry HE, Bennett KA, Galloway TS, Godley BJ, Santillo D, Lindeque PK (2019). What goes in, must come out: Combining scat-based molecular diet analysis and quantification of ingested microplastics in a marine top predator.
Methods in Ecology and Evolution,
10(10), 1712-1722.
Abstract:
What goes in, must come out: Combining scat-based molecular diet analysis and quantification of ingested microplastics in a marine top predator
Microplastics (plastic particles
Abstract.
Easman ES, Abernethy KE, Godley BJ (2018). Assessing public awareness of marine environmental threats and conservation efforts.
Marine Policy,
87, 234-240.
Abstract:
Assessing public awareness of marine environmental threats and conservation efforts
To successfully integrate and engage the general public into marine conservation decisions it is important that individuals are well informed. This study surveyed two sample groups, marine environmental professionals working in the UK, n = 61, and members of the public surveyed in Truro, Cornwall, UK, n = 71. Public awareness of marine environmental threats and conservation efforts was assessed through comparison with the, assumed well informed, professional sample. Findings suggest that the public are generally well informed of threats to the marine environment, but are significantly less well informed about marine conservation and management strategies. Furthermore, despite indicating concern for the marine environment, members of the public display significantly fewer pro-environmental behaviours than marine conservation professionals. Public knowledge (and action) gaps are discussed as well as how these may be minimised, including a more interdisciplinary and active approach to science communication and public engagement.
Abstract.
Patrício AR, Varela MR, Barbosa C, Broderick AC, Catry P, Hawkes LA, Regalla A, Godley BJ (2018). Climate change resilience of a globally important sea turtle nesting population.
Global Change BiologyAbstract:
Climate change resilience of a globally important sea turtle nesting population.
Few studies have looked into climate change resilience of populations of wild animals. We use a model higher vertebrate, the green sea turtle, as its life history is fundamentally affected by climatic conditions, including temperature-dependent sex determination and obligate use of beaches subject to sea level rise (SLR). We use empirical data from a globally important population in West Africa to assess resistance to climate change within a quantitative framework. We project 200 years of primary sex ratios (1900-2100) and create a digital elevation model of the nesting beach to estimate impacts of projected SLR. Primary sex ratio is currently almost balanced, with 52% of hatchlings produced being female. Under IPCC models, we predict: (a) an increase in the proportion of females by 2100 to 76%-93%, but cooler temperatures, both at the end of the nesting season and in shaded areas, will guarantee male hatchling production; (b) IPCC SLR scenarios will lead to 33.4%-43.0% loss of the current nesting area; (c) climate change will contribute to population growth through population feminization, with 32%-64% more nesting females expected by 2120; (d) as incubation temperatures approach lethal levels, however, the population will cease growing and start to decline. Taken together with other factors (degree of foraging plasticity, rookery size and trajectory, and prevailing threats), this nesting population should resist climate change until 2100, and the availability of spatial and temporal microrefugia indicates potential for resilience to predicted impacts, through the evolution of nest site selection or changes in nesting phenology. This represents the most comprehensive assessment to date of climate change resilience of a marine reptile using the most up-to-date IPCC models, appraising the impacts of temperature and SLR, integrated with additional ecological and demographic parameters. We suggest this as a framework for other populations, species and taxa.
Abstract.
Snape RTE, Broderick AC, Çiçek BA, Fuller WJ, Tregenza N, Witt MJ, Godley BJ (2018). Conflict between Dolphins and a Data-Scarce Fishery of the European Union.
Human Ecology,
46(3), 423-433.
Abstract:
Conflict between Dolphins and a Data-Scarce Fishery of the European Union
Fisheries depredation by marine mammals is an economic concern worldwide. We combined questionnaires, acoustic monitoring, and participatory experiments to investigate the occurrence of bottlenose dolphins in the fisheries of Northern Cyprus, and the extent of their conflict with set-nets, an economically important metier of Mediterranean fisheries. Dolphins were present in fishing grounds throughout the year and were detected at 28% of sets. Net damage was on average six times greater where dolphins were present, was correlated with dolphin presence, and the associated costs were considerable. An acoustic deterrent pinger was tested, but had no significant effect although more powerful pingers could have greater impact. However, our findings indicate that effective management of fish stocks is urgently required to address the overexploitation that is likely driving depredation behaviour in dolphins, that in turn leads to net damage and the associated costs to the fisheries.
Abstract.
Bradshaw PJ, Broderick AC, Carreras C, Fuller W, Snape RTE, Wright LI, Godley BJ (2018). Defining conservation units with enhanced molecular tools to reveal fine scale structuring among Mediterranean green turtle rookeries.
Biological Conservation,
222, 253-260.
Abstract:
Defining conservation units with enhanced molecular tools to reveal fine scale structuring among Mediterranean green turtle rookeries
Understanding the connectivity among populations is a key research priority for species of conservation concern. Genetic tools are widely used for this purpose, but the results can be limited by the resolution of the genetic markers in relation to the species and geographic scale. Here, we investigated natal philopatry in green turtles (Chelonia mydas) from four rookeries within close geographic proximity (~200 km) on the Mediterranean island of Cyprus. We genotyped hypervariable mtSTRs, a mtDNA control region sequence (CR) and 13 microsatellite loci to genetically characterise 479 green turtles using markers with different modes of inheritance. We demonstrated matrilineal stock structure for the first time among Mediterranean green turtle rookeries. This result contradicts previous regional assessments and supports a growing body of evidence that green turtles exhibit a more precise level of natal site fidelity than has commonly been recognised. The microsatellites detected weak male philopatry with significant stock structure among three of the six pairwise comparisons. The absence of Atlantic CR haplotypes and mtSTRs amongst these robust sample sizes reaffirms the reproductive isolation of Mediterranean green turtles and supports their status as a subpopulation. A power analysis effectively demonstrated that the mtDNA genetic markers previously employed to evaluate regional stock identity were confounded by an insufficient resolution considering the recent colonisation of this region. These findings improve the regional understanding of stock connectivity and illustrate the importance of using suitable genetic markers to define appropriate units for management and conservation.
Abstract.
Omeyer LCM, Fuller WJ, Godley BJ, Snape RTE, Broderick AC (2018). Determinate or indeterminate growth? Revisiting the growth strategy of sea turtles.
Marine Ecology Progress Series,
596, 199-211.
Abstract:
Determinate or indeterminate growth? Revisiting the growth strategy of sea turtles
Traditionally, growth can be either determinate, ceasing during the natural lifespan of individuals, or indeterminate, persisting throughout life. Although indeterminate growth is a widely accepted strategy and believed to be ubiquitous among long-lived species, it may not be as common as previously thought. Sea turtles are believed to be indeterminate growers despite the paucity of long-term studies into post-maturity growth. In this study, we provide the first temporal analysis of post-maturity growth rates in wild living sea turtles, using 26 yr of data on individual measurements of females nesting in Cyprus. We used generalised additive/linear mixed models to incorporate multiple growth measurements for each female and model post-maturity growth over time. We found post-maturity growth to persist in green Chelonia mydas and loggerhead Caretta caretta turtles, with growth decreasing for approximately 14 yr before plateauing around zero for a further decade solely in green turtles. We also found growth to be independent of size at sexual maturity in both species. Additionally, although annual growth and compound annual growth rates were higher in green turtles than in loggerhead turtles, this difference was not statistically significant. While indeterminate growth is believed to be a key life-history trait of ectothermic vertebrates, here, we provide evidence of determinate growth in green and loggerhead turtles and suggest that determinate growth is a life-history trait shared by cheloniid species. Our results highlight the need for long-term studies to refine life-history models and further our understanding of ageing and longevity of wild sea turtles for conservation and management.
Abstract.
Clay TA, Mangel JC, Alfaro-Shigueto J, Hodgson DJ, Godley BJ (2018). Distribution and habitat use of a cryptic small cetacean, the Burmeister's porpoise, monitored from a small-scale fishery platform.
Frontiers in Marine Science,
5(JUL).
Abstract:
Distribution and habitat use of a cryptic small cetacean, the Burmeister's porpoise, monitored from a small-scale fishery platform
There is widespread evidence that small-scale fisheries (SSF) bycatch threatens many populations of small cetaceans, yet conservation efforts are often limited by a lack of basic knowledge regarding their abundance, distribution, and habitat use. Here, we used passive acoustic monitoring from an SSF platform-of-opportunity to better characterize the distribution and habitat use of small cetaceans in northern Peru, focussing on the little-known Burmeister's porpoise Phocoena spinipinnis. From 2009 to 2012, acoustic click detectors (C-PODs) were attached to fishing nets for the duration of 116 fishing sets (30 fishing trips). Dolphins (unspecified delphinids) and porpoises were recorded around 71 and 22% of fishing sets, respectively. The probability of occurrence and buzzing behavior (a proxy for foraging), and time spent, were linked to both static and dynamic environmental variables to examine the drivers of habitat use. Dolphin activity was spread evenly throughout the fishing area and was not linked to any habitat variables. In contrast, porpoises were detected in neritic waters, and habitat models performed well, identifying preferences for shallow (< 200 m depth) and cooler (17-18°C) waters, close (< 50 km) to shore. The high bycatch rate of small cetaceans in Peruvian SSF gave us the unique opportunity to investigate the link between bycatch and cetacean activity around vessels. We found a positive relationship between the likelihood of a bycatch event and acoustic presence for both dolphins and porpoises, however as we did not know the timing of entanglement, we could not link vocalization rates to mortality events. Nonetheless, as small cetaceans (particularly dolphins) frequently encounter fishing boats, the likelihood of entanglements may be reduced through effective efforts to alert animals to the presence of the net, either acoustically (using acoustic alarms) or visually. This study demonstrates that passive acoustic monitoring from a fisheries platform can provide insights into the distribution and habitat use of small cetaceans at relatively low cost, and is likely to be suitable in regions with low monitoring effort and high fishing pressure.
Abstract.
Mangel JC, Wang J, Alfaro-Shigueto J, Pingo S, Jimenez A, Carvalho F, Swimmer Y, Godley BJ (2018). Illuminating gillnets to save seabirds and the potential for multi-taxa bycatch mitigation.
Royal Society Open Science,
5(7).
Abstract:
Illuminating gillnets to save seabirds and the potential for multi-taxa bycatch mitigation
Bycatch in net fisheries is recognized as a major source of mortality for many marine species, including seabirds. Few mitigation solutions, however, have been identified. We assessed the effectiveness of illuminating fishing nets with green light emitting diodes (LEDs) to reduce the incidental capture of seabirds. Experiments were conducted in the demersal, set gillnet fishery of Constante, Peru and compared 114 pairs of control and illuminated nets. We observed captures of a total of 45 guanay cormorants (Phalacrocorax bougainvillii), with 39 caught in control nets and six caught in illuminated nets. Seabird bycatch in terms of catch-per-unit-effort was significantly (p < 0.05) higher in control nets than in illuminated nets, representing an 85.1% decline in the cormorant bycatch rate. This study, showing that net illumination reduces seabird bycatch and previous studies showing reductions in sea turtle bycatch without reducing target catch, indicates that net illumination can be an effective multi-taxa bycatch mitigation technique. This finding has broad implications for bycatch mitigation in net fisheries given LED technology’s relatively low cost, the global ubiquity of net fisheries and the current paucity of bycatch mitigation solutions.
Abstract.
Mangel JC, Wang J, Alfaro-Shigueto J, Pingo S, Jimenez A, Carvalho F, Swimmer Y, Godley BJ (2018). Illuminating gillnets to save seabirds and the potential for multi-taxa bycatch mitigation.
ROYAL SOCIETY OPEN SCIENCE,
5(7).
Author URL.
Wildermann NE, Gredzens C, Avens L, BarriosGarrido HA, Bell I, Blumenthal J, Bolten AB, McNeill JB, Casale P, Di Domenico M, et al (2018). Informing research priorities for immature sea turtles through expert elicitation.
Endangered Species Research,
37, 55-76.
Abstract:
Informing research priorities for immature sea turtles through expert elicitation
Although sea turtles have received substantial focus worldwide, research on the immature life stages is still relatively limited. The latter is of particular importance, given that a large proportion of sea turtle populations comprises immature individuals. We set out to identify knowledge gaps and identify the main barriers hindering research in this field. We analyzed the perceptions of sea turtle experts through an online survey which gathered their opinions on the current state of affairs on immature sea turtle research, including species and regions in need of further study, priority research questions, and barriers that have interfered with the advancement of research. Our gap analysis indicates that studies on immature leatherback Dermochelys coriacea and hawksbill Eretmochelys imbricata turtles are lacking, as are studies on all species based in the Indian, South Pacific, and South Atlantic Oceans. Experts also perceived that studies in population ecology, namely on survivorship and demography, and habitat use/behavior, are needed to advance the state of knowledge on immature sea turtles. Our survey findings indicate the need for more interdisciplinary research, collaborative efforts (e.g. data-sharing, joint field activities), and improved communication among researchers, funding bodies, stakeholders, and decision-makers.
Abstract.
Nelms SE, Galloway TS, Godley BJ, Jarvis DS, Lindeque PK (2018). Investigating microplastic trophic transfer in marine top predators.
Environmental Pollution,
238, 999-1007.
Abstract:
Investigating microplastic trophic transfer in marine top predators
Microplastics are highly bioavailable to marine organisms, either through direct ingestion, or indirectly by trophic transfer from contaminated prey. The latter has been observed for low-trophic level organisms in laboratory conditions, yet empirical evidence in high trophic-level taxa is lacking. In natura studies face difficulties when dealing with contamination and differentiating between directly and indirectly ingested microplastics. The ethical constraints of subjecting large organisms, such as marine mammals, to laboratory investigations hinder the resolution of these limitations. Here, these issues were resolved by analysing sub-samples of scat from captive grey seals (Halichoerus grypus) and whole digestive tracts of the wild-caught Atlantic mackerel (Scomber scombrus) they are fed upon. An enzymatic digestion protocol was employed to remove excess organic material and facilitate visual detection of synthetic particles without damaging them. Polymer type was confirmed using Fourier-Transform Infrared (FTIR) spectroscopy. Extensive contamination control measures were implemented throughout. Approximately half of scat subsamples (48%; n = 15) and a third of fish (32%; n = 10) contained 1-4 microplastics. Particles were mainly black, clear, red and blue in colour. Mean lengths were 1.5 mm and 2 mm in scats and fish respectively. Ethylene propylene was the most frequently detected polymer type in both. Our findings suggest trophic transfer represents an indirect, yet potentially major, pathway of microplastic ingestion for any species whose feeding ecology involves the consumption of whole prey, including humans. Microplastic trophic transfer in marine top predators is poorly understood; this study using captive seals found that half of the scat sub-samples and a third of the wild caught fish they were fed on contained 1-4 microplastics, indicating transfer from prey to predator.
Abstract.
Casale P, Broderick AC, Caminas JA, Cardona L, Carreras C, Demetropoulos A, Fuller WJ, Godley BJ, Hochscheid S, Kaska Y, et al (2018). Mediterranean sea turtles: current knowledge and priorities for conservation and research.
ENDANGERED SPECIES RESEARCH,
36, 229-267.
Author URL.
Tikochinski Y, Bradshaw P, Mastrogiacomo A, Broderick A, Daya A, Demetropoulos A, Demetropoulos S, Eliades NG, Fuller W, Godley B, et al (2018). Mitochondrial DNA short tandem repeats unveil hidden population structuring and migration routes of an endangered marine turtle.
Aquatic Conservation: Marine and Freshwater Ecosystems,
28(4), 788-797.
Abstract:
Mitochondrial DNA short tandem repeats unveil hidden population structuring and migration routes of an endangered marine turtle
The assessment of the composition and dynamics of endangered populations is crucial for management and conservation, and appropriate genetic markers are critical. The genetic structuring of the Mediterranean green turtle (Chelonia mydas) populations and the origin of the stranded animals found along the Israeli coast was investigated using new highly polymorphic short tandem repeat (STR) markers. The structuring of nesting populations was studied using pairwise genetic distances and a principal coordinates analysis (PCoA). The contribution of the different nesting populations to the stranded sample was assessed by using a mixed-stock analysis. A clear population genetic structure, not detected before, has been revealed. The four nesting populations are genetically well differentiated, and thus should be considered as different management units. The populations from Turkey and Israel showed higher resemblance, despite residing at opposite ends of the Mediterranean distribution. The Turkish nesting population is the main source of the stranded turtles sampled along the Israeli shore, confirming that individuals from this population migrate from north to south along the eastern shore of the Mediterranean, as previously shown by telemetry studies. The use of a highly polymorphic haplotyping method enabled the detection of a clear genetic structuring of the green turtle populations in the eastern Mediterranean Sea that was not revealed in previous studies, demonstrating the importance of marker selection in population genetics. The analysis of the genetic composition of the stranded turtles allowed us to investigate the migration patterns from nesting to foraging areas, supporting previous satellite-tracking and stable-isotope results. These results will help to delineate conservation management units for the species in the Mediterranean, and reveal connectivity among beaches and mixed aggregations.
Abstract.
Patrício AR, Varela MR, Barbosa C, Broderick AC, Ferreira Airaud MB, Godley BJ, Regalla A, Tilley D, Catry P (2018). Nest site selection repeatability of green turtles, Chelonia mydas, and consequences for offspring.
Animal Behaviour,
139, 91-102.
Abstract:
Nest site selection repeatability of green turtles, Chelonia mydas, and consequences for offspring
Nest site selection is a critical behaviour, particularly in species with no parental care, as it can greatly impact offspring survival. Marine turtles depend on sandy beaches to nest, where they select from a range of microhabitats that may differently affect hatchling survival and phenotype. Here we describe the degree of nest site selection at one of the largest green turtle rookeries globally, in Guinea-Bissau, West Africa, and how this impacts offspring. In 2013 and 2014 we recorded the spatial distribution of 1559 nests, and monitored 657 females during oviposition, to assess population and individual preferences on nesting site. Overall, females tended to nest close to the vegetation, at a preferred elevation of 4.8–5.0 m, which was above the highest spring tide (4.7 m), enhancing clutch survival. Individuals displayed high repeatability in nesting microhabitat type (open sand, forest border and forest), distance along the beach, distance to the vegetation and elevation, which may result from this behaviour having a genetic basis or from fine-scale nest site philopatry. Hatchlings from cooler nests were larger, potentially dispersing faster and more able to evade predators, while smaller hatchlings, from warmer nests, retained more energetic reserves (residual yolk), which may also be advantageous for initial dispersal, particularly if food is scarce. Thus, individual preferences in nest site selection led to trade-offs in offspring phenotype, but overall, most nesting females selected sites that increased offspring survival, suggesting that nest site selection is an adaptive trait that has been under selection. As under future climate change scenarios females nesting in upper shaded areas should have higher fitness, individual consistency in nesting microhabitat provides opportunity for natural selection to occur.
Abstract.
Snape RTE, Bradshaw PJ, Broderick AC, Fuller WJ, Stokes KL, Godley BJ (2018). Off-the-shelf GPS technology to inform marine protected areas for marine turtles.
Biological Conservation,
227, 301-309.
Abstract:
Off-the-shelf GPS technology to inform marine protected areas for marine turtles
The financial expense of tracking solutions often impedes effective characterisation of habitat use in threatened marine megavertebrates. Yet some of these taxa predictably aggregate at coastal breeding sites, providing conservation opportunities. Toward a low-cost solution for tracking marine megavertebrates, we trial conventional GPS data loggers against Argos satellite transmitters for assessing inter-nesting habitat use of marine turtles. Devices were attached to green (Chelonia mydas) and loggerhead (Caretta caretta) turtles nesting at a study site in Cyprus, where patrol teams were in place to retrieve GPS loggers from turtles returning to lay subsequent clutches. GPS tracking revealed loggerhead turtles to predominantly use areas outside the boundaries of an MPA proposed for the region, while both species under-used much of the MPA area. Due to high location error, Argos data were considered unsuitable for such fine-scale assessments (all location classes except Z were included in our analysis). However, Argos tracking showed half the loggerhead turtles sampled also nested outside of the patrolled study area, demonstrating connectivity with other proposed MPAs. This was not accounted for by GPS tracking, because females exhibiting this behaviour rarely returned to the study beach, precluding GPS retrieval, thus, demonstrating the power of remote data access. The low-cost GPS technology could be considered in similar cases, where recapture is likely and where funding barriers preclude the use of Argos-relay fast-acquisition GPS technology. In combining the accuracy GPS and the continuity of Argos, the latter provides the best solution in most scenarios, but at far greater cost.
Abstract.
Bartholomew DC, Mangel JC, Alfaro-Shigueto J, Pingo S, Jimenez A, Godley BJ (2018). Remote electronic monitoring as a potential alternative to on-board observers in small-scale fisheries. Biological Conservation, 219, 35-45.
Oppel S, Bolton M, Carneiro APB, Dias MP, Green JA, Masello JF, Phillips RA, Owen E, Quillfeldt P, Beard A, et al (2018). Spatial scales of marine conservation management for breeding seabirds.
Marine Policy,
98, 37-46.
Abstract:
Spatial scales of marine conservation management for breeding seabirds
Knowing the spatial scales at which effective management can be implemented is fundamental for conservation planning. This is especially important for mobile species, which can be exposed to threats across large areas, but the space use requirements of different species can vary to an extent that might render some management approaches inefficient. Here the space use patterns of seabirds were examined to provide guidance on whether conservation management approaches should be tailored for taxonomic groups with different movement characteristics. Seabird tracking data were synthesised from 5419 adult breeding individuals of 52 species in ten families that were collected in the Atlantic Ocean basin between 1998 and 2017. Two key aspects of spatial distribution were quantified, namely how far seabirds ranged from their colony, and to what extent individuals from the same colony used the same areas at sea. There was evidence for substantial differences in patterns of space-use among the ten studied seabird families, indicating that several alternative conservation management approaches are needed. Several species exhibited large foraging ranges and little aggregation at sea, indicating that area-based conservation solutions would have to be extremely large to adequately protect such species. The results highlight that short-ranging and aggregating species such as cormorants, auks, some penguins, and gulls would benefit from conservation approaches at relatively small spatial scales during their breeding season. However, improved regulation of fisheries, bycatch, pollution and other threats over large spatial scales will be needed for wide-ranging and dispersed species such as albatrosses, petrels, storm petrels and frigatebirds.
Abstract.
Hart CE, Maldonado-Gasca A, Ley-Quiñonez CP, Flores-Peregrina M, De Jesús Romero-Villarruel J, Aranda-Mena OS, Plata-Rosas LJ, Tena-Espinoza M, Llamas-González I, Zavala-Norzagaray AA, et al (2018). Status of Olive Ridley Sea Turtles (Lepidochelys olivacea) after 29 Years of Nesting Rookery Conservation in Nayarit and Bahía de Banderas, Mexico.
Chelonian Conservation and Biology,
17(1), 27-36.
Abstract:
Status of Olive Ridley Sea Turtles (Lepidochelys olivacea) after 29 Years of Nesting Rookery Conservation in Nayarit and Bahía de Banderas, Mexico
Olive ridleys (Lepidochelys olivacea) are the most numerous sea turtle species worldwide and also locally along the Pacific coast of Mexico. Published data on their distribution and nesting abundance along the coast of Nayarit and northern Jalisco, Mexico are, however, scarce. Here we describe the current extent of conservation activities and the history of efforts to protect sea turtles along this 394-km stretch of coastline. We found that 110 km (of the total of 394 km) are monitored by 18 sea turtle conservation programs, which in 2015 accounted for 43.2% of the total shoreline. Olive ridley sea turtle nesting was encountered on all monitored beaches. Our use of hatchery-protected nests as a measure of nesting levels is undoubtedly an underestimate of overall nesting in the region; however, it nevertheless provides a baseline of current nesting intensity in sites under conservation. Bahía de Banderas presented the highest nesting levels in the study area with 46.4% (3742±904; mean±SD) of the total protected nests (8073±547) while only representing 14.2% (15.4±3.8 km) of the total area monitored (109.6±4.5 km). The results provided here represent a valuable baseline upon which future research and assessments can be built when analyzing the sea turtle conservation progress in the region.
Abstract.
Rees AF, Avens L, Ballorain K, Bevan E, Broderick AC, Carthy RR, Christianen MJA, Duclos G, Heithaus MR, Johnston DW, et al (2018). The potential of unmanned aerial systems for sea turtle research and conservation: a review and future directions.
Endangered Species Research,
35, 81-100.
Abstract:
The potential of unmanned aerial systems for sea turtle research and conservation: a review and future directions
The use of satellite systems and manned aircraft surveys for remote data collection has been shown to be transformative for sea turtle conservation and research by enabling the collection of data on turtles and their habitats over larger areas than can be achieved by surveys on foot or by boat. Unmanned aerial vehicles (UAVs) or drones are increasingly being adopted to gather data, at previously unprecedented spatial and temporal resolutions in diverse geographic locations. This easily accessible, low-cost tool is improving existing research methods and enabling novel approaches in marine turtle ecology and conservation. Here we review the diverse ways in which incorporating inexpensive UAVs may reduce costs and field time while improving safety and data quality and quantity over existing methods for studies on turtle nesting, at-sea distribution and behaviour surveys, as well as expanding into new avenues such as surveillance against illegal take. Furthermore, we highlight the impact that high-quality aerial imagery captured by UAVs can have for public outreach and engagement. This technology does not come without challenges. We discuss the potential constraints of these systems within the ethical and legal frameworks which researchers must operate and the difficulties that can result with regard to storage and analysis of large amounts of imagery. We then suggest areas where technological development could further expand the utility of UAVs as data-gathering tools; for example, functioning as downloading nodes for data collected by sensors placed on turtles. Development of methods for the use of UAVs in sea turtle research will serve as case studies for use with other marine and terrestrial taxa.
Abstract.
Duncan EM, Arrowsmith J, Bain C, Broderick AC, Lee J, Metcalfe K, Pikesley SK, Snape RTE, van Sebille E, Godley BJ, et al (2018). The true depth of the Mediterranean plastic problem: Extreme microplastic pollution on marine turtle nesting beaches in Cyprus.
Marine Pollution Bulletin,
136, 334-340.
Abstract:
The true depth of the Mediterranean plastic problem: Extreme microplastic pollution on marine turtle nesting beaches in Cyprus
We sampled 17 nesting sites for loggerhead (Caretta caretta) and green turtles (Chelonia mydas) in Cyprus. Microplastics (
Abstract.
Nuno A, Blumenthal JM, Austin TJ, Bothwell J, Ebanks-Petrie G, Godley BJ, Broderick AC (2018). Understanding implications of consumer behavior for wildlife farming and sustainable wildlife trade.
Conserv Biol,
32(2), 390-400.
Abstract:
Understanding implications of consumer behavior for wildlife farming and sustainable wildlife trade.
Unsustainable wildlife trade affects biodiversity and the livelihoods of communities dependent upon those resources. Wildlife farming has been proposed to promote sustainable trade, but characterizing markets and understanding consumer behavior remain neglected but essential steps in the design and evaluation of such operations. We used sea turtle trade in the Cayman Islands, where turtles have been farm raised for human consumption for almost 50 years, as a case study to explore consumer preferences toward wild-sourced (illegal) and farmed (legal) products and potential conservation implications. Combining methods innovatively (including indirect questioning and choice experiments), we conducted a nationwide trade assessment through in-person interviews from September to December 2014. Households were randomly selected using disproportionate stratified sampling, and responses were weighted based on district population size. We approached 597 individuals, of which 37 (6.2%) refused to participate. Although 30% of households had consumed turtle in the previous 12 months, the purchase and consumption of wild products was rare (e.g. 64-742 resident households consumed wild turtle meat [i.e. 0.3-3.5% of households] but represented a large threat to wild turtles in the area due to their reduced populations). Differences among groups of consumers were marked, as identified through choice experiments, and price and source of product played important roles in their decisions. Despite the long-term practice of farming turtles, 13.5% of consumers showed a strong preference for wild products, which demonstrates the limitations of wildlife farming as a single tool for sustainable wildlife trade. By using a combination of indirect questioning, choice experiments, and sales data to investigate demand for wildlife products, we obtained insights about consumer behavior that can be used to develop conservation-demand-focused initiatives. Lack of data from long-term social-ecological assessments hinders the evaluation of and learning from wildlife farming. This information is key to understanding under which conditions different interventions (e.g. bans, wildlife farming, social marketing) are likely to succeed.
Abstract.
Author URL.
Alfaro-Shigueto J, Mangel JC, Darquea J, Donoso M, Baquero A, Doherty PD, Godley BJ (2018). Untangling the impacts of nets in the southeastern Pacific: Rapid assessment of marine turtle bycatch to set conservation priorities in small-scale fisheries.
FISHERIES RESEARCH,
206, 185-192.
Author URL.
Metcalfe K, Bréheret N, Chauvet E, Collins T, Curran BK, Parnell RJ, Turner RA, Witt MJ, Godley BJ (2018). Using satellite AIS to improve our understanding of shipping and fill gaps in ocean observation data to support marine spatial planning.
Journal of Applied Ecology,
55(4), 1834-1845.
Abstract:
Using satellite AIS to improve our understanding of shipping and fill gaps in ocean observation data to support marine spatial planning
A key stage underpinning marine spatial planning (MSP) involves mapping the spatial distribution of ecological processes and biological features as well the social and economic interests of different user groups. One sector, merchant shipping (vessels that transport cargo or passengers), however, is often poorly represented in MSP due to a perceived lack of fine-scale spatially explicit data to support decision-making processes. Here, using the Republic of Congo as an example, we show how publicly accessible satellite-derived automatic identification system (S-AIS) data can address gaps in ocean observation data for shipping at a national scale. We also demonstrate how fine-scale (0.05 km2 resolution) spatial data layers derived from S-AIS (intensity, occupancy) can be used to generate maps of vessel pressure to provide an indication of patterns of impact on the marine environment and potential for conflict with other ocean user-groups. We reveal that passenger vessels, offshore service vessels, bulk carrier and cargo vessels and tankers account for 93.7% of all vessels and vessel traffic annually, and that these sectors operate in a combined area equivalent to 92% of Congo's exclusive economic zone—far exceeding the areas allocated for other user groups (conservation, fisheries and petrochemicals). We also show that the shallow coastal waters and habitats of the continental shelf are subject to more persistent pressure associated with shipping, and that the potential for conflict among user groups is likely to be greater with fisheries, whose zones are subject to the highest vessel pressure scores than with conservation or petrochemical sectors. Synthesis and applications. Shipping dominates ocean use, and so excluding this sector from decision-making could lead to increased conflict among user groups, poor compliance and negative environmental impacts. This study demonstrates how satellite-derived Automatic Identification System data can provide a comprehensive mechanism to fill gaps in ocean observation data and visualise patterns of vessel behaviour and potential threats to better support marine spatial planning at national scales.
Abstract.
Obregón C, Lyndon AR, Barker J, Christiansen H, Godley BJ, Kurland S, Piccolo JJ, Potts R, Short R, Tebb A, et al (2018). Valuing and understanding fish populations in the Anthropocene: key questions to address.
Journal of Fish Biology,
92(3), 828-845.
Abstract:
Valuing and understanding fish populations in the Anthropocene: key questions to address
Research on the values of fish populations and fisheries has primarily focused on bio-economic aspects; a more nuanced and multidimensional perspective is mostly neglected. Although a range of social aspects is increasingly being considered in fisheries research, there is still no clear understanding as to how to include these additional values within management policies nor is there a cogent appreciation of the major knowledge gaps that should be tackled by future research. This paper results from a workshop held during the 50th anniversary symposium of the Fisheries Society of the British Isles at the University of Exeter, UK, in July 2017. Here, we aim to highlight the current knowledge gaps on the values of fish populations and fisheries thus directing future research. To this end, we present eight questions that are deeply relevant to understanding the values of fish populations and fisheries. These can be applied to all habitats and fisheries, including freshwater, estuarine and marine.
Abstract.
Casale P, Abitsi G, Aboro MP, Agamboue PD, Agbode L, Allela NL, Angueko D, Bibang Bi Nguema JN, Boussamba F, Cardiec F, et al (2017). A first estimate of sea turtle bycatch in the industrial trawling fishery of Gabon.
Biodiversity and Conservation,
26(10), 2421-2433.
Abstract:
A first estimate of sea turtle bycatch in the industrial trawling fishery of Gabon
Gabon hosts nesting grounds for several sea turtle species, including the world’s largest rookery for the leatherback turtle (Dermochelys coriacea), Africa’s largest rookery for the olive ridley turtle (Lepidochelys olivacea) and smaller aggregations of the hawksbill turtle (Eretmochelys imbricata) and green turtle (Chelonia mydas). To assess the level of incidental captures of turtles by the Gabonese trawl fishery, an onboard observer program was conducted in the period 2012–2013. A total of 143 turtles were captured by 15 trawlers during 271 fishing days. The olive ridley turtle was the main species captured (80% of bycaught turtles), with mostly adult-sized individuals. The remaining 20% included green turtles, hawksbill turtles, leatherback turtles and undetermined species. Bycatch per unit of effort (BPUE) of olive ridley turtles varied greatly depending on the period of the year (range of means: 0.261–2.270). Dead and comatose turtles were 6.2 and 24.6% respectively (n = 65). By applying the available fishing effort to two BPUE scenarios (excluding or considering a seasonal peak), the total annual number of captures was estimated as ranging between 1026 (CI 95% 746–1343) and 2581 (CI 95% 1641–3788) olive ridley turtles, with a mortality ranging from 63 (CI 95% 13–135) to 794 (CI 95% 415–1282) turtles per year depending on the scenario and on the fate of comatose turtles. Such a potential mortality may be reason for concern for the local breeding population of olive ridley turtles and recommendations in terms of possible conservation measures and further research are given.
Abstract.
Duncan EM, Botterell ZLR, Broderick AC, Galloway TS, Lindeque PK, Nuno A, Godley BJ (2017). A global review of marine turtle entanglement in anthropogenic debris: a baseline for further action.
ENDANGERED SPECIES RESEARCH,
34, 431-448.
Author URL.
Campbell E, Alfaro-Shigueto J, Godley BJ, Mangel JC (2017). Abundance estimate of the Amazon River dolphin (Inia geoffrensis) and the tucuxi (Sotalia fluviatilis) in southern Ucayali, Peru.
LATIN AMERICAN JOURNAL OF AQUATIC RESEARCH,
45(5), 957-969.
Author URL.
Weber SB, Weber N, Godley BJ, Pelembe T, Stroud S, Williams N, Broderick AC (2017). Ascension Island as a mid-Atlantic developmental habitat for juvenile hawksbill turtles.
Journal of the Marine Biological Association of the United Kingdom,
97(4), 813-820.
Abstract:
Ascension Island as a mid-Atlantic developmental habitat for juvenile hawksbill turtles
Ascension Island in the South Atlantic Ocean is renowned for its globally-important nesting population of green turtles (Chelonia mydas) that has been the subject of long-term research. By comparison, very little is known about the apparently small population of hawksbill turtles (Eretmochelys imbricata) that have been recorded in its waters, thousands of kilometres from known nesting beaches. Here, we collate 10 years of in-water tagging data, opportunistic public sighting records and underwater observations to provide a baseline for future research, and present preliminary data on habitat use derived from two individuals fitted with GPS transmitters. Although public sightings were inevitably biased towards popular recreation areas, the resulting distribution suggests that hawksbill turtles occur year round in Ascension Island's waters along the entire 65 km of coastline. Hawksbills were observed feeding on benthic algae and encrusting sponges, and were frequently seen scavenging on fish discards around the Island's pier at night aided by anthropogenic lighting. Between 2003 and 2013, 35 turtles were captured, measured, tagged and then released. Curved carapace lengths ranged from 33.5 to 85 cm (mean = 48.8 cm) indicating that most (if not all) individuals encountered around Ascension are post-pelagic juveniles. Four individuals were recaptured at least once giving a mean minimum residence time of 4.2 yr (range: 2.8-7.3 yr) and a mean growth rate of 2.8 cm yr-1. Turtles fitted with Fastloc™ GPS devices remained at Ascension Island for the duration of the study (>90 days) and occupied restricted home ranges with an average area of 2.5 km2 and an average 'core use area' (50% utilization distribution) of 0.05 km2. Together, these results suggest that Ascension Island serves as a mid-Atlantic developmental habitat for benthic-feeding, juvenile hawksbill turtles on extended oceanic migrations before recruiting to their adult foraging grounds, likely to be located in Brazil or tropical West Africa.
Abstract.
Humber F, Andriamahaino ET, Beriziny T, Botosoamananto R, Godley BJ, Gough C, Pedron S, Ramahery V, Broderick AC (2017). Assessing the small-scale shark fishery of Madagascar through community-based monitoring and knowledge.
Fisheries Research,
186, 131-143.
Abstract:
Assessing the small-scale shark fishery of Madagascar through community-based monitoring and knowledge
Over 90% of those employed in commercial capture fisheries work in the small-scale fisheries (SSF) sector and an estimated 97% of small scale fishers are found in least developed countries. However, the capacity for monitoring SSF globally is low and there is a paucity of data, in particular for remote areas within developing nations. The methods presented here demonstrate a low cost participatory approach for gathering data on small-scale fisheries, in particular for those that take place across remote areas. Community-based data collectors were trained to record biological and socioeconomic data on the traditional (non-motorised) shark fishery in the Toliara region of Madagascar over a six year period (2007–2012). An estimated 20 species of shark were recorded, of which 31% (n = 3505) were Sphyrna lewini (scalloped hammerhead), a species listed by the IUCN as Endangered (IUCN, 2016). Although the number of sharks landed annually has not decreased during our survey period, there was a significant decrease in the average size of sharks caught. Despite multiple anecdotal reports of shark population declines, interviews and focus groups highlight the possibility that shark landings appear to have been maintained through changes in gear and increases in effort (eg. number of fishers, time spent fishing), which may mask a decline in shark populations. The numbers of sharks taken by the traditional fishery in our study region was estimated to be between 65,000 and 104,000 year−1, whilst estimates using national export and import of dried shark fin from Madagascar, and shark length data in this study, put total landings between 78,000 and 471,851 year−1. Reliable data on the total volume of sharks landed in Madagascar's waters is scarce, in particular from foreign industrial boats both directly targeting shark species and as bycatch in fisheries targeting other species. There is currently no legislation in place to protect sharks from overexploitation in Madagascar and an urgent need to address the lack of shark fishery management across the traditional, artisanal and industrial fisheries.
Abstract.
Patrício AR, Marques A, Barbosa C, Broderick AC, Godley BJ, Hawkes LA, Rebelo R, Regalla A, Catry P (2017). Balanced primary sex ratios and resilience to climate change in a major sea turtle population.
Marine Ecology Progress Series,
577, 189-203.
Abstract:
Balanced primary sex ratios and resilience to climate change in a major sea turtle population
Global climate change is expected to have major impacts on biodiversity. Sea turtles have temperature-dependent sex determination, and many populations produce highly femalebiased offspring sex ratios, a skew likely to increase further with global warming. We estimated the primary sex ratio at one of the world's largest green turtle Chelonia mydas rookeries in Guinea-Bissau, West Africa, and explored its resilience to climate change. In 2013 and 2014, we deployed data loggers recording nest (n = 101) and sand (n = 30) temperatures, and identified hatchling sex by histological examination of gonads. A logistic curve was fitted to the data to allow predictions of sex ratio across habitats and through the nesting season. The population-specific pivotal temperature was 29.4°C, with both sexes produced within incubation temperatures from 27.6 to 31.4°C: the transitional range of temperatures (TRT). Primary sex ratio changed from maleto female-biased across relatively small temporal and spatial scales. Overall it was marginally female-biased, but we estimated an exceptionally high male hatchling production of 47.7% (95% CI: 36.7-58.3%) and 44.5% (95% CI: 33.8-55.4%) in 2013 and 2014, respectively. Both the temporal and spatial variation in incubation conditions and the wide range of the TRT suggest resilience and potential for adaptation to climate change if the present nesting habitat remains unchanged. These findings underline the importance of assessing site-specific parameters to understand populations' responses to climate change, particularly with regard to identifying rookeries with high male hatchling production that may be key for the future conservation of sea turtles under projected global warming scenarios.
Abstract.
Hancock JM, Furtado S, Merino S, Godley BJ, Nuno A (2017). Exploring drivers and deterrents of the illegal consumption and trade of marine turtle products in Cape Verde, and implications for conservation planning.
ORYX,
51(3), 428-436.
Abstract:
Exploring drivers and deterrents of the illegal consumption and trade of marine turtle products in Cape Verde, and implications for conservation planning
Conservation regulations aimed at restricting resource use are commonly used to manage and protect natural resources but their implementation depends on the compliance of resource users. The design of effective regulations should be informed by an understanding of the factors that affect compliance, considering contextual socio-economic information. Changes have been implemented in the national legislation protecting marine turtles in the Cape Verde archipelago, where historical and recent records indicate heavy human predation pressure on nesting and foraging marine turtles. We present an assessment of levels of illegal harvesting and consumption of marine turtle products on two of the islands, Boa Vista and Santiago, and an analysis of their potential drivers. Key stakeholders were interviewed to investigate the perceived impact of the main interventions employed in Cape Verde to reduce illegal harvesting, trade and consumption of marine turtles. Despite an apparent decrease in harvesting and consumption, our results suggest there has been a shift from subsistence harvesting to trade in Boa Vista. The existence of laws to protect marine turtles was perceived as a deterrent to harvesting, and awareness campaigns and a lack of availability were perceived as reasons for the decrease in consumption in Boa Vista and Santiago, respectively. Aiming to inform ongoing discussions, we recommend a multi-targeted approach focusing on both suppliers and consumers to magnify conservation effectiveness. Regular impact evaluation focusing on harvest and consumption is needed to improve the design of regulations and inform policy decision making.
Abstract.
Omeyer LCM, Godley BJ, Broderick AC (2017). Growth rates of adult sea turtles.
ENDANGERED SPECIES RESEARCH,
34, 357-371.
Author URL.
Dawson TM, Formia A, Agamboué PD, Asseko GM, Boussamba F, Cardiec F, Chartrain E, Doherty PD, Fay JM, Godley BJ, et al (2017). Informing Marine Protected Area Designation and Management for Nesting Olive Ridley Sea Turtles Using Satellite Tracking. Frontiers in Marine Science, 4
Humber F, Godley BJ, Nicolas T, Raynaud O, Pichon F, Broderick A (2017). Placing Madagascar's marine turtle populations in a regional context using community-based monitoring.
ORYX,
51(3), 542-553.
Abstract:
Placing Madagascar's marine turtle populations in a regional context using community-based monitoring
Madagascar is an important foraging ground for marine turtles in the Western Indian Ocean, yet the status of the country's nesting aggregations remains poorly documented. We assess the current status and trend in nesting throughout Madagascar, including data recorded by a community-based monitoring project in the Barren Isles (western Madagascar). We contextualize the findings in comparison with data from Madagascar's closest neighbouring states. Reports indicate that nesting levels have declined at many coastal sites, with no known recordings since 2000 at > 40 nesting sites. We estimate there are a minimum of 1,200 nests per year in Madagascar, with the largest recorded nesting aggregation (< 1,000 nests per year) found on islands off the west and northern coasts. The majority of nesting aggregations, including those recorded by the community-based monitoring project in the Barren Isles, are relatively small, in the order of < 50 nests per year, yet they are potentially important sources of regional genetic diversity. Nesting on many of the islands (e.g. Tromelin, Europa) around Madagascar has increased over the last 20 years, despite the fact that thousands of turtles probably originating from these sites are taken by fishers in the waters of Madagascar annually. We discuss the importance of protecting small nesting populations, and how community-based monitoring could be an important tool for conserving remote and vulnerable populations and building capacity for natural resource management.
Abstract.
Williams SM, Weber SB, Oppel S, Leat EHK, Sommerfeld J, Godley BJ, Weber N, Broderick AC (2017). Satellite Telemetry Reveals the First Record of the Ascension Frigatebird (Fregata aquila) for the Americas.
Wilson Journal of Ornithology,
129(3), 600-604.
Abstract:
Satellite Telemetry Reveals the First Record of the Ascension Frigatebird (Fregata aquila) for the Americas
We present the first record of the Ascension Frigatebird (Fregata aquila) for the Americas by retrieving coordinates from an individual equipped with a satellite transmitting device. As part of a wider study on the spatial and behavioral ecology of this species, we tracked a single juvenile frigatebird that entered into Brazilian waters as defined in the guidelines set forth by the Brazilian Ornithological Records Committee and the South American Checklist Committee. In total, this individual traveled ∼45,000 km over a 3.5-month period before transmissions ceased close to the exclusive economic zone of Sierra Leone. Based on the potential for this species to wander, the Ascension Frigatebird should be considered when attempting to identify any frigatebird in the Atlantic Ocean. Importantly, this record demonstrates the great potential for satellite telemetry to inform national ornithological and conservation organizations on the presence of pelagic seabirds that may otherwise be overlooked by visual surveys.
Abstract.
Bradshaw PJ, Broderick AC, Carreras C, Inger R, Fuller W, Snape R, Stokes KL, Godley BJ (2017). Satellite tracking and stable isotope analysis highlight differential recruitment among foraging areas in green turtles.
MARINE ECOLOGY PROGRESS SERIES,
582, 201-214.
Author URL.
Oppel S, Weber S, Weber N, Fox D, Leat E, Sim J, Sommerfeld J, Bolton M, Broderick AC, Godley BJ, et al (2017). Seasonal shifts in foraging distribution due to individual flexibility in a tropical pelagic forager, the Ascension frigatebird.
Marine Ecology Progress Series,
585, 199-212.
Abstract:
Seasonal shifts in foraging distribution due to individual flexibility in a tropical pelagic forager, the Ascension frigatebird
Predators exploiting tropical pelagic waters characterised by low fluctuations in seasonal temperature and salinity may require different foraging strategies than predators that can rely on persistently productive marine features. Consistent individual differences in foraging strategies have been found in temperate seabirds, but it is unclear whether such foraging special-isation would be beneficial in unpredictable tropical pelagic waters. We examined whether foraging trip characteristics of a tropical seabird were consistent between seasons and within individuals and explored whether seasonal changes could be explained by environmental variables. Ascension frigatebird Fregata aquila trips lasted up to 18 d and covered a total travel distance of up to 7047 km, but adult frigatebirds stayed within a radius of 1150 km of Ascension Island. We found that the 50% utilisation distribution of the population expanded southwestward in the cool season due to individuals performing more and longer trips in a southerly and westerly direction during the cool compared to the hot season. Individual repeatability was low (R < 0.25) for all trip characteristics, and we were unable to explain seasonal changes in time spent at sea using oceanographic or atmospheric variables. Instead, frigatebird usage per area was almost exclusively determined by distance from the colony, and although individuals spent more time in distant portions of their foraging trips, the amount of time spent per unit area decreased exponentially with increasing distance from the colony. This study indicates that, in a relatively featureless environment, high individual consistency may not be a beneficial trait for pelagic predators.
Abstract.
Cox SL, Witt MJ, Embling CB, Godley BJ, Hosegood PJ, Miller PI, Votier SC, Ingram SN (2017). Temporal patterns in habitat use by small cetaceans at an oceanographically dynamic marine renewable energy test site in the Celtic Sea.
Deep-Sea Research Part II: Topical Studies in Oceanography,
141, 178-190.
Abstract:
Temporal patterns in habitat use by small cetaceans at an oceanographically dynamic marine renewable energy test site in the Celtic Sea
Shelf-seas are highly dynamic and oceanographically complex environments, which likely influences the spatio-temporal distributions of marine megafauna such as marine mammals. As such, understanding natural patterns in habitat use by these animals is essential when attempting to ascertain and assess the impacts of anthropogenically induced disturbances, such as those associated with marine renewable energy installations (MREIs). This study uses a five year (2009–2013) passive acoustics (C-POD) dataset to examine the use of an oceanographically dynamic marine renewable energy test site by small cetaceans, dolphins (unspecified delphinids) and harbour porpoises Phocoena phocoena, in the southern Celtic Sea. To examine how temporal patterns in habitat use across the site related to oceanographic changes occurring over broad seasonal scales as well as those driven by fine scale (bi-weekly) localised processes (that may be masked by seasonal trends), separate analyses were conducted using (1) all daily animal detection rates spanning the entire five year dataset and (2) daily animal detection rates taken only during the summer months (defined as mid-June to mid-October) of 2010 (when continuous monitoring was carried out at multiple discrete locations across the site). In both instances, generalised additive mixed effects models (GAMMs) were used to link detection rates to a suite of environmental variables representative of the oceanography of the region. We show that increased harbour porpoise detection rates in the late winter/early spring (January–March) are associated with low sea surface temperatures (SST), whilst peaks in dolphin detection rates in the summer (July–September) coincide with increased SSTs and the presence of a tidal-mixing front. Moreover, across the summer months of 2010, dolphin detection rates were found to respond to small scale changes in SST and position in the spring-neap cycle, possibly reflective of a preference for the stratified waters immediately offshore of the front. Together, these findings suggest that habitat use by small cetaceans within shelf-seas is temporally variable, species specific and likely driven by complex bottom-up processes. As such, the effective conservation management of shelf-seas requires that we understand the dynamic complexities of these systems and the species that inhabit them. In particular, we emphasise the need for a good understanding of the natural drivers of habitat use by marine megafauna before the potential impacts of anthropogenically induced disturbances, such as those associated with the construction, maintenance and operation of MREIs, can be assessed.
Abstract.
Metcalfe K, Collins T, Abernethy KE, Boumba R, Dengui JC, Miyalou R, Parnell RJ, Plummer KE, Russell DJF, Safou GK, et al (2016). Addressing Uncertainty in Marine Resource Management; Combining Community Engagement and Tracking Technology to Characterize Human Behavior.
Conservation Letters,
10(4), 459-468.
Abstract:
Addressing Uncertainty in Marine Resource Management; Combining Community Engagement and Tracking Technology to Characterize Human Behavior
© 2016 the Authors. Conservation Letters published by Wiley Periodicals, Inc. Small-scale fisheries provide an essential source of food and employment for coastal communities, yet the availability of detailed information on the spatiotemporal distribution of fishing effort to support resource management at a country level is scarce. Here, using a national-scale study in the Republic of Congo, we engaged with fishers from 23 of 28 small-scale fisheries landing sites along the coast to demonstrate how combining community engagement and relatively low cost Global Positioning System (GPS) trackers can rapidly provide fine-scale information on: (1) the behavioral dynamics of the fishers and fleets that operate within this sector; and (2) the location, size and attributes of important fishing grounds upon which communities are dependent. This multidisciplinary approach should be considered within a global context where uncertainty over the behavior of marine and terrestrial resource-users can lead to management decisions that potentially compromise local livelihoods, conservation, and resource sustainability goals.
Abstract.
Bicknell AWJ, Godley BJ, Sheehan EV, Votier SC, Witt MJ (2016). Camera technology for monitoring marine biodiversity and human impact.
Frontiers in Ecology and the Environment,
14(8), 424-432.
Abstract:
Camera technology for monitoring marine biodiversity and human impact
Human activities have fundamentally altered the marine environment, creating a need for effective management in one of Earth's most challenging habitats. Remote camera imagery has emerged as an essential tool for monitoring at all scales, from individuals to populations and communities up to entire marine ecosystems. Here we review the use of remote cameras to monitor the marine environment in relation to human activity, and consider emerging and potential future applications. Rapid technological advances in equipment and analytical tools influence where, why, and how remote camera imagery can be applied. We encourage the inclusion of cameras within multi-method and multi-sensor approaches to improve our understanding of ecosystems and help manage human activities and minimize impacts.
Abstract.
Greaves D, Conley D, Magagna D, Aires E, Chambel Leitão J, Witt M, Embling CB, Godley BJ, Bicknell AWJ, Saulnier JB, et al (2016). Environmental Impact Assessment: Gathering experiences from wave energy test centres in Europe.
International Journal of Marine Energy,
14, 68-79.
Abstract:
Environmental Impact Assessment: Gathering experiences from wave energy test centres in Europe
The wave energy industry is an emerging sector and a new user of maritime space that has potential to contribute significantly to the EU renewable energy goals. International and national regulatory frameworks necessitate Environmental Impact Assessments (EIA) that provide important data to inform development consent decisions. Here we have evaluated experience related to the assessment programmes at EU wave energy test centres combined with knowledge gained from EIA produced for other similar renewable energy developments. From this we have identified key receptors of concern, as well as the type and magnitude of impacts which may be expected. The key environmental receptors of concern for wave energy EIA include the physical environment (e.g. morphology, waves and current) and flora and fauna1 as represented by marine mammals, seabirds, benthos, fish and shellfish. From a review of the EIAs performed at wave energy test centres, we identified several lessons regarding the wave energy EIA process. There is clear evidence that the receptors of primary interest are dependent on factors such as the local environmental characteristics, the presence/absence of protected species and the regulatory authority under which the EIA is performed. Furthermore, it is recommended that concerns relating to cumulative impacts, from an expanding level of wave energy development taking place in a background of growing utilisation of the marine environment, which are largely unknown at this early stage of the industry may be comprehensively addressed at the national level as part of a Strategic Environmental Assessment (EIA) and/or in Maritime Spatial Planning (MSP) and that it should be regularly reassessed.
Abstract.
Colman LP, Patrício ARC, McGowan A, Santos AJB, Marcovaldi MÂ, Bellini C, Godley BJ (2016). Long-term growth and survival dynamics of green turtles (Chelonia mydas) at an isolated tropical archipelago in Brazil.
Marine Biology,
162(1), 111-122.
Abstract:
Long-term growth and survival dynamics of green turtles (Chelonia mydas) at an isolated tropical archipelago in Brazil
© 2014, Springer-Verlag Berlin Heidelberg.For effective management of species of conservation concern, knowledge of life history parameters is essential. Here, we present the results of one of the longest ongoing capture-mark-recapture studies of juvenile green turtles (Chelonia mydas) worldwide. From 1988 to 2013, 1,279 individual turtles were tagged in Fernando de Noronha, Brazil (3°51′S, 32°25′W). The size distribution at first capture varied between 27 and 87 cm (mean ± SD 47.9 ± 11.3 cm) curved carapace length (CCL). Median residence time was 2.4 year (with long-term residence of up to 11.2 year), with individuals exhibiting some site fidelity within the Archipelago. Turtles at this site are slow growing (mean 2.6 ± 1.6 cm year−1; range −0.9 to 7.9 cm year−1; n = 1,022), with a non-monotonic expected growth rate function and a peak in growth rates occurring at 50–60 cm CCL. At these rates, turtles in Fernando de Noronha would need to spend ca. 22 years to grow from 30 to 87 cm CCL and even longer to reach minimum adult breeding size. A Cormack–Jolly–Seber model was used to estimate the apparent survival of the residents and recapture probabilities (2001–2012). The estimated annual abundance ranged from 420 to 1,148 individuals. Confidence around abundance estimates was low, and there was no significant trend over the period, despite steep recent increases at the major source rookery. Slow growth and stable stocking numbers may be suggestive of density-dependent regulation having taken place following initial population recovery that occurred prior to the current study.
Abstract.
Garrett JK, Blondel P, Godley BJ, Pikesley SK, Witt MJ, Johanning L (2016). Long-term underwater sound measurements in the shipping noise indicator bands 63 Hz and 125 Hz from the port of Falmouth Bay, UK. Marine Pollution Bulletin, 110(1), 438-448.
Varo-Cruz N, Bermejo JA, Calabuig P, Cejudo D, Godley BJ, López-Jurado LF, Pikesley SK, Witt MJ, Hawkes LA (2016). New findings about the spatial and temporal use of the Eastern Atlantic Ocean by large juvenile loggerhead turtles.
Diversity and DistributionsAbstract:
New findings about the spatial and temporal use of the Eastern Atlantic Ocean by large juvenile loggerhead turtles
© 2016 John Wiley & Sons Ltd. Aims: Effective conservation of threatened or endangered species requires a robust understanding of their spatio-temporal distribution. Although a huge amount is known about the movements of Atlantic adult sea turtles, much less is known about juvenile turtles, and much of the life history model is therefore inferred. We set out to describe the spatio-temporal distribution of juvenile loggerheads turtles found around the Canary Islands. Location: Eastern North Atlantic Ocean. Methods: Between 1999 and 2012, we satellite-tracked 24 healthy large juvenile loggerhead turtles (mean straight carapace length = 47.4 cm, range = 34.6-54.5 cm) captured in the waters around the Canary Islands. We describe their regional distribution, identify high-use areas and create a model for habitat suitability using minimum convex polygons, density rasters and ensemble ecological niche modelling, integrated with physical and biological environmental data. Results: Turtles used a huge oceanic area (2.5 million km2) with particularly high usage around the Canary Islands, Spain, Portugal, Morocco and Western Sahara. In spring and summer, turtles generally moved further north towards the Iberian Peninsula. Ecological niche modelling identified sea surface temperature as the most important contributory variable to the habitat models. We also recorded three juvenile turtles making westward migrations away from the eastern Atlantic Ocean, presumably back towards their original natal beaches near sexual maturity. Main conclusions: the results of the present study provide insight into a significant knowledge gap on the spatio-temporal distribution of large juvenile loggerhead turtles in the eastern Atlantic Ocean. The data highlight that turtles occupy a vast open oceanic area, which hampers the ability of static conservation approaches to afford effective protection. However, ensemble ecological niche modelling highlights key suitable habitat for juvenile loggerhead turtles, which could be used in dynamic conservation protection.
Abstract.
Patrício AR, Diez CE, Van Dam RP, Godley BJ (2016). Novel insights into the dynamics of green turtle fibropapillomatosis.
Marine Ecology Progress Series,
547, 247-255.
Abstract:
Novel insights into the dynamics of green turtle fibropapillomatosis
Outbreaks of fibropapillomatosis (FP), a neoplastic infectious disease of marine turtles, have occurred worldwide since the 1980s. Its most likely aetiological agent is a virus, but disease expression depends on external factors, typically associated with altered environments. The scarcity of robust long-term data on disease prevalence has limited interpretations on the impacts of FP on turtle populations. Here we model the dynamics of FP at 2 green turtle foraging aggregations in Puerto Rico, through 18 yr of capture-mark-recapture data (1997-2014). We observed spatiotemporal variation in FP prevalence, potentially modulated via individual site-fidelity. FP ex pression was residency dependent, and FP-free individuals developed tumours after 1.8 ± 0.8 yr (mean ± SD) in the infected area. Recovery from the disease was likely, with complete tumour regression occurring in 2.7 ± 0.7 yr (mean ± SD). FP does not currently seem to be a major threat to marine turtle populations; however, disease prevalence is yet unknown in many areas. Systematic monitoring is highly advisable as human-induced stressors can lead to deviations in host- pathogen relationships and disease virulence. Finally, data collection should be standardized for a global assessment of FP dynamics and impacts.
Abstract.
Pikesley SK, Godley BJ, Latham H, Richardson PB, Robson LM, Solandt J-L, Trundle C, Wood C, Witt MJ (2016). Pink sea fans (Eunicella verrucosa) as indicators of the spatial efficacy of Marine Protected Areas in southwest UK coastal waters. Marine Policy, 64, 38-45.
Nelms SE, Duncan EM, Broderick AC, Galloway TS, Godfrey MH, Hamann M, Lindeque PK, Godley BJ (2016). Plastic and marine turtles: a review and call for research.
ICES JOURNAL OF MARINE SCIENCE,
73(2), 165-181.
Author URL.
Rees AF, Alfaro-Shigueto J, Barata PCR, Bjorndal KA, Bolten AB, Bourjea J, Broderick AC, Campbell LM, Cardona L, Carreras C, et al (2016). Review: Are we working towards global research priorities for management and conservation of sea turtles?. Endangered Species Research, 31, 337-382.
Jeffers VF, Godley BJ (2016). Satellite tracking in sea turtles: How do we find our way to the conservation dividends?.
Biological Conservation,
199, 172-184.
Abstract:
Satellite tracking in sea turtles: How do we find our way to the conservation dividends?
As species of conservation concern, sea turtles have historically been difficult to study because of their elusive nature and extensive ranges, but improvements in telemetry have facilitated insights into life histories and behaviours which can potentially inform conservation policies. To date, there have been few assessments of the impact of satellite tracking data on species conservation, and it is difficult to clearly gauge whether the dividends justify the costs. Through an extensive review of the literature (369 papers, 1982-2014) and a questionnaire-based survey of 171 sea turtle tracking researchers, we evaluate the conservation dividends gained thus far from tracking and highlight conservation successes. We discuss who is tracking and where, where biases in effort exist, and evaluate the impact of tracking data on conservation. Conservation issues are increasingly being considered. Where research recommends policy change, the quality of advice varies and the level of uptake is still uncertain, with few clearly described examples of tracking-data actually influencing policy. The means to increase the conservation impact are discussed, including: disseminating findings more widely; communicating and collaborating with colleagues and stakeholders for more effective data sharing; community liaison, and endeavouring to close the gaps between researchers and conservation practitioners.
Abstract.
Nelms SE, Piniak WED, Weir CR, Godley BJ (2016). Seismic surveys and marine turtles: an underestimated global threat?.
Biological Conservation,
193, 49-65.
Abstract:
Seismic surveys and marine turtles: an underestimated global threat?
Seismic surveys are widely used in marine geophysical oil and gas exploration, employing airguns to produce sound-waves capable of penetrating the sea floor. In recent years, concerns have been raised over the biological impacts of this activity, particularly for marine mammals. While exploration occurs in the waters of at least fifty countries where marine turtles are present, the degree of threat posed by seismic surveys is almost entirely unknown. To investigate this issue, a mixed-methods approach involving a systematic review, policy comparison and stakeholder analysis was employed and recommendations for future research were identified. This study found that turtles have been largely neglected both in terms of research and their inclusion in mitigation policies. Few studies have investigated the potential for seismic surveys to cause behavioural changes or physical damage, indicating a crucial knowledge gap. Possible ramifications for turtles include exclusion from critical habitats, damage to hearing and entanglement in seismic survey equipment. Despite this, the policy comparison revealed that only three countries worldwide currently include turtles in their seismic mitigation guidelines and very few of the measures they specify are based on scientific evidence or proven effectiveness. Opinions obtained from stakeholder groups further highlight the urgent need for directed, in-depth empirical research to better inform and develop appropriate mitigation strategies. As seismic surveying is becoming increasingly widespread and frequent, it is important and timely that we evaluate the extent to which marine turtles, a taxon of global conservation concern, may be affected.
Abstract.
Snape RTE, Broderick AC, Çiçek BA, Fuller WJ, Glen F, Stokes K, Godley BJ (2016). Shelf life: Neritic habitat use of a turtle population highly threatened by fisheries.
Diversity and Distributions,
22(7), 797-807.
Abstract:
Shelf life: Neritic habitat use of a turtle population highly threatened by fisheries
Aim: it is difficult to mitigate threats to marine vertebrates until their habitat use is understood. We report on a decade of satellite tracking loggerhead turtles (Caretta caretta) from an important nesting site to determine priority habitats for their protection in a region where they are known to be heavily impacted by fisheries. Location: Cyprus, Eastern Mediterranean. Method: We tracked 27 adult female loggerheads between 2001 and 2012 from North Cyprus nesting beaches. To eliminate potential biases, we included females nesting on all coasts of our study area, at different periods of the nesting season and from a range of size classes. Results: Foraging sites were distributed over the continental shelf of Cyprus, the Levant and North Africa, up to a maximum distance of 2100 km from nesting sites. Foraging sites were clustered in (1) near-shore waters of Cyprus and Syria, (2) offshore waters of Egypt and (3) offshore and near-shore regions of Libya and Tunisia. The North Cyprus and west Egypt/east Libyan coasts are important areas for loggerhead turtles during migration. Movement patterns within foraging sites strongly suggest benthic feeding in discrete areas. Early nesters visited other rookeries in Turkey, Syria and Israel where they likely laid further clutches. Tracking suggests minimum annual mortality of 11%, comparable to other fishery-impacted loggerhead populations. Main conclusions: This work further highlights the importance of neritic habitats of Libya and Tunisia as areas likely used by loggerhead turtles from many of the Mediterranean rookeries and where the threat of fisheries bycatch is high. Our tracking data also suggest that anthropogenic mortalities may have occurred in North Cyprus, Syria and Egypt; all within near-shore marine areas where small-scale fisheries operate. Protection of this species across many geopolitical units is a major challenge and documenting their distribution is an important first step.
Abstract.
Hawkes LA, Witt MJ, Godley BJ, Broderick AC, McGowan A, Bjorndal KA, Bolten AB, Chaloupka M, Van Dam RP, Diez CE, et al (2016). Somatic growth dynamics of West Atlantic hawksbill sea turtles: a spatio-temporal perspective. Ecosphere, 7
Mills CA, Godley BJ, Hodgson DJ (2016). Take Only Photographs, Leave Only Footprints: Novel Applications of Non-Invasive Survey Methods for Rapid Detection of Small, Arboreal Animals.
PLoS One,
11(1).
Abstract:
Take Only Photographs, Leave Only Footprints: Novel Applications of Non-Invasive Survey Methods for Rapid Detection of Small, Arboreal Animals.
The development of appropriate wildlife survey techniques is essential to promote effective and efficient monitoring of species of conservation concern. Here, we demonstrate the utility of two rapid-assessment, non-invasive methods to detect the presence of elusive, small, arboreal animals. We use the hazel dormouse, Muscardinus avellanarius, a rodent of conservation concern, as our focal species. Prevailing hazel dormouse survey methods are prolonged (often taking months to years to detect dormice), dependent on season and habitat, and/or have low detection rates. Alternatives would be of great use to ecologists who undertake dormouse surveys, especially those assessing the need for mitigation measures, as legally required for building development projects. Camera traps and footprint tracking are well-established tools for monitoring elusive large terrestrial mammals, but are rarely used for small species such as rodents, or in arboreal habitats. In trials of these adapted methods, hazel dormice visited bait stations and were successfully detected by both camera traps and tracking equipment at each of two woodland study sites, within days to weeks of installation. Camera trap images and footprints were of adequate quality to allow discrimination between two sympatric small mammal species (hazel dormouse and wood mouse, Apodemus sylvaticus). We discuss the relative merits of these methods with respect to research aims, funds, time available and habitat.
Abstract.
Author URL.
Stringell TB, Clerveaux WV, Godley BJ, Kent FEA, Lewis EDG, Marsh JE, Phillips Q, Richardson PB, Sanghera A, Broderick AC, et al (2016). Taxonomic distinctness in the diet of two sympatric marine turtle species.
Marine Ecology,
37(5), 1036-1049.
Abstract:
Taxonomic distinctness in the diet of two sympatric marine turtle species
Marine turtles are considered keystone consumers in tropical coastal ecosystems and their decline through overexploitation has been implicated in the deterioration of reefs and seagrass pastures in the Caribbean. In the present study, we analysed stomach contents of green (Chelonia mydas) and hawksbill turtles (Eretmochelys imbricata) harvested in the legal turtle fishery of the Turks and Caicos Islands (Caribbean) during 2008–2010. Small juveniles to adult-sized turtles were sampled. Together with data from habitat surveys, we assessed diet composition and the taxonomic distinctness (and other species diversity measures) in the diets of these sympatric marine turtle species. The diet of green turtles (n�=�92) consisted of a total of 47 taxa: including three species of seagrass (present in 99% of individuals), 29 species of algae and eight sponge species. Hawksbill turtles (n�=�45) consumed 73 taxa and were largely spongivorous (16 species; sponges present in 100% of individuals) but also foraged on 50 species of algae (present in 73% of individuals) and three species of seagrass. Plastics were found in trace amounts in 4% of green turtle and 9% of hawksbill turtle stomach samples. We expected to find changes in diet that might reflect ontogenetic shifts from small (oceanic-pelagic) turtles to larger (coastal-benthic) turtles. Dietary composition (abundance and biomass), however, did not change significantly with turtle size, although average taxonomic distinctness was lower in larger green turtles. There was little overlap in prey between the two turtle species, suggesting niche separation. Taxonomic distinctness routines indicated that green turtles had the most selective diet, whereas hawksbill turtles were less selective than expected when compared with the relative frequency and biomass of diet items. We discuss these findings in relation to the likely important trophic roles that these sympatric turtle species play in reef and seagrass habitats.
Abstract.
Merchant ND, Brookes KL, Faulkner RC, Bicknell AWJ, Godley BJ, Witt MJ (2016). Underwater noise levels in UK waters.
Scientific Reports,
6(1).
Abstract:
Underwater noise levels in UK waters
AbstractUnderwater noise from human activities appears to be rising, with ramifications for acoustically sensitive marine organisms and the functioning of marine ecosystems. Policymakers are beginning to address the risk of ecological impact, but are constrained by a lack of data on current and historic noise levels. Here, we present the first nationally coordinated effort to quantify underwater noise levels, in support of UK policy objectives under the EU Marine Strategy Framework Directive (MSFD). Field measurements were made during 2013–2014 at twelve sites around the UK. Median noise levels ranged from 81.5–95.5 dB re 1 μPa for one-third octave bands from 63–500 Hz. Noise exposure varied considerably, with little anthropogenic influence at the Celtic Sea site, to several North Sea sites with persistent vessel noise. Comparison of acoustic metrics found that the RMS level (conventionally used to represent the mean) was highly skewed by outliers, exceeding the 97th percentile at some frequencies. We conclude that environmental indicators of anthropogenic noise should instead use percentiles, to ensure statistical robustness. Power analysis indicated that at least three decades of continuous monitoring would be required to detect trends of similar magnitude to historic rises in noise levels observed in the Northeast Pacific.
Abstract.
Revuelta O, León YM, Broderick AC, Feliz P, Godley BJ, Balbuena JA, Mason A, Poulton K, Savoré S, Raga JA, et al (2015). Assessing the efficacy of direct conservation interventions: Clutch protection of the leatherback marine turtle in the Dominican Republic.
ORYX,
49(4), 677-686.
Abstract:
Assessing the efficacy of direct conservation interventions: Clutch protection of the leatherback marine turtle in the Dominican Republic
The beaches of Jaragua National Park in the Dominican Republic are the country's last known major nesting site for the leatherback marine turtle Dermochelys coriacea. This nesting aggregation is threatened by widespread illegal egg take, and clutch relocation and artificial incubation have been carried out as protection measures since 1974. We assess the efficacy of such efforts and investigate how artificial incubation may be influencing the success and sex ratios of clutches. We compare hatching success, incubation duration and embryo mortality in in-situ clutches (n = 43) with those incubated artificially at sites in the east and west of the Park (n = 35 and n = 31, respectively). Our results show that in the west, artificial incubation significantly decreases hatching success in clutches. In the east the duration of incubation is increased, which we predict would result in an increase in the number of males from these clutches. Clutch relocation is currently the only viable conservation option for clutches on eastern beaches because of illegal egg take but action is needed to ensure that the natural sex ratio is not distorted. However, on the western beaches in situ clutch incubation seems possible through beach protection. Further community engagement and enforcement are required to improve conservation measures at eastern beaches if long-term, less sustainable intervention is to be avoided.
Abstract.
Humber F, Andriamahefazafy M, Godley BJ, Broderick AC (2015). Endangered, essential and exploited: How extant laws are not enough to protect marine megafauna in Madagascar.
Marine Policy,
60, 70-83.
Abstract:
Endangered, essential and exploited: How extant laws are not enough to protect marine megafauna in Madagascar
The decline of many marine megafauna species is of global concern; but many of these species, in particular marine mammals, have been afforded international and national protection and are the focus of conservation programmes. The existing national and international legislation are reviewed through which marine megavertebrates are afforded protection in Malagasy waters. The decline and protection of marine megafauna has followed a familiar pattern in Madagascar, with two main exceptions: marine turtles and elasmobranchs remain heavily exploited by national and international fishing fleets. The status of legislation governing both taxa is unclear and unknown by many working within the fisheries and marine sector. In Madagascar, marine turtles are fully protected from exploitation by national regulations in conjunction with a number of multilateral agreements. The numerous pieces of legislation that protect marine turtles are not coherent, regularly misunderstood and rarely enforced. Madagascar is taking steps to improve protection of marine turtles through the development of a national strategy, but it is recommended that the opportunity is also taken to improve understanding of current legislation and work more closely with local communities that consider turtle fishing a customary practice. Elasmobranchs however, receive minimal legal protection and only those listed under multilateral agreements are bound by any potential future management. Where legislation does exist to help manage elasmobranchs (eg. bycatch stipulations for foreign fishing vessels) it is incomplete and difficult to enforce. It is also recommended that Madagascar puts in place national elasmobranch legislation to help prevent their continued overfishing, especially in the face of increasing numbers of elasmobranch species on CITES and CMS. As such, both groups of species are rendered effectively unprotected and are in danger of overexploitation. With the growth and proliferation of locally managed marine areas (LMMAs) in Madagascar the potential for local communities to increase protection and management of these species should be considered, especially with the limited capacity available to monitor and enforce legislation along such a vast coastline.
Abstract.
Revuelta O, Hawkes L, León YM, Godley BJ, Raga JA, Tomás J (2015). Evaluating the importance of Marine Protected Areas for the conservation of hawksbill turtles Eretmochelys imbricata nesting in the Dominican Republic.
Endangered Species Research,
27(2), 169-180.
Abstract:
Evaluating the importance of Marine Protected Areas for the conservation of hawksbill turtles Eretmochelys imbricata nesting in the Dominican Republic
Understanding spatial and temporal habitat-use patterns to protect both foraging and breeding grounds of species of concern is crucial for successful conservation. Saona Island in Del Este National Park (DENP), south-eastern Dominican Republic (DR), hosts the only major hawksbill (Eretmochelys imbricata) nesting area in the DR (100 nests yr-1, SD = 8.4, range = 93-111), with the population having been critically reduced through hunting. We satellite tracked 9 female hawksbill turtles, and present analyses of their core-use areas with respect to Marine Protected Areas (MPAs) in both their internesting and foraging areas. Kernel utilization distributions indicated that during the internesting period all turtles remained close to their nesting beaches in small home ranges in the territorial waters of the DR, mostly over the continental shelf (
Abstract.
Hammerschlag N, Broderick AC, Coker JW, Coyne MS, Dodd M, Frick MG, Godfrey MH, Godley BJ, Griffin DB, Hartog K, et al (2015). Evaluating the landscape of fear between apex predatory sharks and mobile sea turtles across a large dynamic seascape. Ecology, 96(8), 2117-2126.
Stringell TB, Clerveaux WV, Godley BJ, Phillips Q, Ranger S, Richardson PB, Sanghera A, Broderick AC (2015). Fisher choice may increase prevalence of green turtle fibropapillomatosis disease. Frontiers in Marine Science, 2
Metcalfe K, Agamboué PD, Augowet E, Boussamba F, Cardiec F, Fay JM, Formia A, Kema Kema JR, Kouerey C, Mabert BDK, et al (2015). Going the extra mile: Ground-based monitoring of olive ridley turtles reveals Gabon hosts the largest rookery in the Atlantic.
Biological Conservation,
190, 14-22.
Abstract:
Going the extra mile: Ground-based monitoring of olive ridley turtles reveals Gabon hosts the largest rookery in the Atlantic
The management of widely dispersed marine vertebrates can be facilitated by better understanding their distribution, density, population trends and threats. Unfortunately, for some populations of sea turtle spatial and temporal data are often lacking, particularly along the Atlantic coast of Africa, a region which is considered globally important. Here we combined spatially limited monitoring data from four nesting beaches over seven seasons with an extensive ground-based coastal survey that covered 585. km of Gabon's Atlantic coast, to provide the first population assessment for the olive ridley turtle Lepidochelys olivacea. This species is currently classified as data deficient by the IUCN in the eastern Atlantic and so is considered a regional conservation priority. Whilst the logistics required to undertake such a comprehensive ground-based census were complicated, the method proved extremely effective in providing population estimates for a widely dispersed marine vertebrate and demonstrates the importance of focusing beyond intensively monitored beaches. In particular, our findings reveal that the presence of nesting activity spans almost the entirety of Gabon's coast, the density of which subsequently reveals that Gabon hosts one of the most important olive ridley rookeries in the Atlantic (2370-9814 clutches, approximating to 948-5452 breeding females per annum and a total estimate of 1422-8178 breeding females), with a significant proportion, 81. ±. 3.5% (mean. ±. 1 S.D.) of total nesting effort occurring within protected areas. These findings thus complement our existing knowledge base and further emphasise the regional and global importance of Gabon's nesting sea turtle populations.
Abstract.
Stokes KL, Broderick AC, Canbolat AF, Candan O, Fuller WJ, Glen F, Levy Y, Rees AF, Rilov G, Snape RT, et al (2015). Migratory corridors and foraging hotspots: Critical habitats identified for Mediterranean green turtles.
Diversity and DistributionsAbstract:
Migratory corridors and foraging hotspots: Critical habitats identified for Mediterranean green turtles
Levels of sea turtle bycatch in the Mediterranean are thought to be unsustainable. We provide a comprehensive overview of adult green turtle (Chelonia mydas) distribution during nesting, migration and foraging phases, highlighting transitory as well as residential areas of high use to facilitate adequate protection for this long-lived, migratory species. Location: Mediterranean Sea. Methods: Thirty-four females were satellite tracked from breeding grounds in the four countries with major nesting (Cyprus, Turkey, Israel and Syria) for a total of 8521 (mean: 251) tracking days in a collaborative effort to summarize the most comprehensive set of distribution data thus far assembled for this species in the Mediterranean. Results: Ten foraging grounds are identified, with two major hotspots in Libya accounting for >50% of turtles tracked to conclusive endpoints. The coastlines of Egypt and Libya contain high densities of migrating turtles following the nesting season, particularly July-September, and likely also pre-nesting (April-June). A high-use seasonal pelagic corridor running south-west from Turkey and Cyprus to Egypt is also evident, used by >50% of all tracked turtles. Main conclusions: Bycatch levels and mortality rates for the key foraging areas and high-density seasonal pathways identified here are largely unknown and should be investigated as a priority. We recommend that the Gulf of Sirte in Libya be explored as a potential biodiversity hotspot and considered for proposal as a marine protected area (MPA). Green turtle fidelity to nesting beaches, foraging areas and migratory pathways renders them vulnerable to localized threats but enables targeted mitigation measures and protection.
Abstract.
Stokes KL, Broderick AC, Canbolat AF, Candan O, Fuller WJ, Glen F, Levy Y, Rees AF, Rilov G, Snape RT, et al (2015). Migratory corridors and foraging hotspots: Critical habitats identified for Mediterranean green turtles.
Diversity and Distributions,
21(6), 665-674.
Abstract:
Migratory corridors and foraging hotspots: Critical habitats identified for Mediterranean green turtles
Aim: Levels of sea turtle bycatch in the Mediterranean are thought to be unsustainable. We provide a comprehensive overview of adult green turtle (Chelonia mydas) distribution during nesting, migration and foraging phases, highlighting transitory as well as residential areas of high use to facilitate adequate protection for this long-lived, migratory species. Location: Mediterranean Sea. Methods: Thirty-four females were satellite tracked from breeding grounds in the four countries with major nesting (Cyprus, Turkey, Israel and Syria) for a total of 8521 (mean: 251) tracking days in a collaborative effort to summarize the most comprehensive set of distribution data thus far assembled for this species in the Mediterranean. Results: Ten foraging grounds are identified, with two major hotspots in Libya accounting for >50% of turtles tracked to conclusive endpoints. The coastlines of Egypt and Libya contain high densities of migrating turtles following the nesting season, particularly July-September, and likely also pre-nesting (April-June). A high-use seasonal pelagic corridor running south-west from Turkey and Cyprus to Egypt is also evident, used by >50% of all tracked turtles. Main conclusions: Bycatch levels and mortality rates for the key foraging areas and high-density seasonal pathways identified here are largely unknown and should be investigated as a priority. We recommend that the Gulf of Sirte in Libya be explored as a potential biodiversity hotspot and considered for proposal as a marine protected area (MPA). Green turtle fidelity to nesting beaches, foraging areas and migratory pathways renders them vulnerable to localized threats but enables targeted mitigation measures and protection.
Abstract.
Pikesley SK, Broderick AC, Cejudo D, Coyne MS, Godfrey MH, Godley BJ, Lopez P, López-Jurado LF, Elsy Merino S, Varo-Cruz N, et al (2015). Modelling the niche for a marine vertebrate: a case study incorporating behavioural plasticity, proximate threats and climate change.
Ecography,
38(8), 803-812.
Abstract:
Modelling the niche for a marine vertebrate: a case study incorporating behavioural plasticity, proximate threats and climate change
The integration of satellite telemetry, remotely sensed environmental data, and habitat/environmental modelling has provided for a growing understanding of spatial and temporal ecology of species of conservation concern. The Republic of Cape Verde comprises the only substantial rookery for the loggerhead turtle Caretta caretta in the eastern Atlantic. A size related dichotomy in adult foraging patterns has previously been revealed for adult sea turtles from this population with a proportion of adults foraging neritically, whilst the majority forage oceanically. Here we describe observed habitat use and employ ecological niche modelling to identify suitable foraging habitats for animals utilising these two distinct behavioural strategies. We also investigate how these predicted habitat niches may alter under the influence of climate change induced oceanic temperature rises. We further contextualise our niche models with fisheries catch data and knowledge of fisheries 'hotspots' to infer threat from fisheries interaction to this population, for animals employing both strategies. Our analysis revealed repeated use of coincident oceanic habitat, over multiple seasons, by all smaller loggerhead turtles, whilst larger neritic foraging turtles occupied continental shelf waters. Modelled habitat niches were spatially distinct, and under the influence of predicted sea surface temperature rises, there was further spatial divergence of suitable habitats. Analysis of fisheries catch data highlighted that the observed and modelled habitats for oceanic and neritic loggerhead turtles could extensively interact with intensive fisheries activity within oceanic and continental shelf waters of northwest Africa. We suggest that the development and enforcement of sustainable management strategies, specifically multi-national fisheries policy, may begin to address some of these issues; however, these must be flexible and adaptive to accommodate potential range shift for this species.
Abstract.
Hart CE, Blanco GS, Coyne MS, Delgado-Trejo C, Godley BJ, Jones TT, Resendiz A, Seminoff JA, Witt MJ, Nichols WJ, et al (2015). Multinational tagging efforts illustrate regional scale of distribution and threats for east pacific green turtles (Chelonia mydas agassizii).
PLoS One,
10(2).
Abstract:
Multinational tagging efforts illustrate regional scale of distribution and threats for east pacific green turtles (Chelonia mydas agassizii).
To further describe movement patterns and distribution of East Pacific green turtles (Chelonia mydas agassizii) and to determine threat levels for this species within the Eastern Pacific. In order to do this we combined published data from existing flipper tagging and early satellite tracking studies with data from an additional 12 satellite tracked green turtles (1996-2006). Three of these were tracked from their foraging grounds in the Gulf of California along the east coast of the Baja California peninsula to their breeding grounds in Michoacán (1337-2928 km). In addition, three post-nesting females were satellite tracked from Colola beach, Michoacán to their foraging grounds in southern Mexico and Central America (941.3-3020 km). A further six turtles were tracked in the Gulf of California within their foraging grounds giving insights into the scale of ranging behaviour. Turtles undertaking long-distance migrations showed a tendency to follow the coastline. Turtles tracked within foraging grounds showed that foraging individuals typically ranged up to 691.6 km (maximum) from release site location. Additionally, we carried out threat analysis (using the cumulative global human impact in the Eastern Pacific) clustering pre-existing satellite tracking studies from Galapagos, Costa Rica, and data obtained from this study; this indicated that turtles foraging and nesting in Central American waters are subject to the highest anthropogenic impact. Considering that turtles from all three rookeries were found to migrate towards Central America, it is highly important to implement conservation plans in Central American coastal areas to ensure the survival of the remaining green turtles in the Eastern Pacific. Finally, by combining satellite tracking data from this and previous studies, and data of tag returns we created the best available distributional patterns for this particular sea turtle species, which emphasized that conservation measures in key areas may have positive consequences on a regional scale.
Abstract.
Author URL.
Scales KL, Miller PI, Varo-Cruz N, Hodgson DJ, Hawkes LA, Godley BJ (2015). Oceanic loggerhead turtles Caretta caretta associate with thermal fronts: Evidence from the Canary Current Large Marine Ecosystem.
Marine Ecology Progress Series,
519, 195-207.
Abstract:
Oceanic loggerhead turtles Caretta caretta associate with thermal fronts: Evidence from the Canary Current Large Marine Ecosystem
Oceanographic fronts are physical interfaces between water masses that differ in properties such as temperature, salinity, turbidity and chlorophyll a enrichment. Bio-physical coupling along fronts can lead to the development of pelagic biodiversity hotspots. A diverse range of marine vertebrates have been shown to associate with fronts, using them as foraging and migration habitats. Elucidation of the ecological significance of fronts generates a better understanding of marine ecosystem functioning, conferring opportunities to improve management of anthropogenic activities in the oceans. This study presents novel insights into the oceanographic drivers of habitat use in a population of marine turtles characterised by an oceanic-neritic foraging dichotomy. Using satellite tracking data from adult female loggerhead turtles Caretta caretta nesting at Cape Verde (n = 12), we tested the hypothesis that oceanic-foraging loggerheads associate with mesocale (10s to 100s of km) thermal fronts. We used high-resolution (1 km) composite front mapping to characterise frontal activity in the Canary Current Large Marine Ecosystem over 2 temporal scales: (1) seasonal front frequency and (2) 7 d front metrics. Our use-availability analysis indicated that oceanic loggerheads show a preference for the highly productive upwelling region between Cape Verde and mainland Africa, an area of intense frontal activity. Within the upwelling region, turtles appear to forage epipelagically around mesoscale thermal fronts, exploiting profitable foraging opportunities resulting from physical aggregation of prey.
Abstract.
Bourjea J, Mortimer JA, Garnier J, Okemwa G, Godley BJ, Hughes G, Dalleau M, Jean C, Ciccione S, Muths D, et al (2015). Population structure enhances perspectives on regional management of the western Indian Ocean green turtle.
Conservation Genetics,
16(5), 1069-1083.
Abstract:
Population structure enhances perspectives on regional management of the western Indian Ocean green turtle
To refine our understanding of the spatial structure of the green turtle (Chelonia mydas) populations in the South West Indian Ocean (SWIO), we analysed patterns of mitochondrial DNA (396 base pairs control region fragment) variation among 171 samples collected at five distinct locations (Kenya, Northern Mozambique, and three locations in the Republic of Seychelles: the Granitic, Amirantes, and Farquhar groups) and compared them to genetic data (n = 288), previously collected from 10 southern locations in the SWIO. We also analysed post-nesting satellite tracks (n = 4) from green turtles nesting in the Amirantes group. Pairwise comparisons of haplotype frequencies showed significant genetic differentiation amongst rookeries and suggest that the SWIO hosts two main genetic stocks of nesting green turtles that could themselves be divided in two sub-stocks that still need to be confirmed: A. the Southern Mozambique Channel, that could be composed of two sub-stocks (a1) Europa and (a2) Juan de Nova, and B. the Northern SWIO (N-SWIO) comprising two sub-stocks (b1) the Seychelles archipelago stock—SEY; and (b2) the remaining Northern SWIO rookeries. The newly revealed differentiation of the Seychelles population is supported by restricted migration of females tracked from the Amirantes group suggesting relatively limited links with other regional stocks. We hypothesize that this differentiation could be due to local and regional current patterns and to the role of the Indo-Pacific Barrier as a genetic break, enhanced during periods of sea level decrease associated with a rare but continuous flow of hatchlings and young juveniles from Western Australia.
Abstract.
Bourjea J, Mortimer JA, Garnier J, Okemwa G, Godley BJ, Hughes G, Dalleau M, Jean C, Ciccione S, Muths D, et al (2015). Population structure enhances perspectives on regional management of the western Indian Ocean green turtle.
Conservation GeneticsAbstract:
Population structure enhances perspectives on regional management of the western Indian Ocean green turtle
To refine our understanding of the spatial structure of the green turtle (Chelonia mydas) populations in the South West Indian Ocean (SWIO), we analysed patterns of mitochondrial DNA (396 base pairs control region fragment) variation among 171 samples collected at five distinct locations (Kenya, Northern Mozambique, and three locations in the Republic of Seychelles: the Granitic, Amirantes, and Farquhar groups) and compared them to genetic data (n = 288), previously collected from 10 southern locations in the SWIO. We also analysed post-nesting satellite tracks (n = 4) from green turtles nesting in the Amirantes group. Pairwise comparisons of haplotype frequencies showed significant genetic differentiation amongst rookeries and suggest that the SWIO hosts two main genetic stocks of nesting green turtles that could themselves be divided in two sub-stocks that still need to be confirmed: A. the Southern Mozambique Channel, that could be composed of two sub-stocks (a1) Europa and (a2) Juan de Nova, and B. the Northern SWIO (N-SWIO) comprising two sub-stocks (b1) the Seychelles archipelago stock—SEY; and (b2) the remaining Northern SWIO rookeries. The newly revealed differentiation of the Seychelles population is supported by restricted migration of females tracked from the Amirantes group suggesting relatively limited links with other regional stocks. We hypothesize that this differentiation could be due to local and regional current patterns and to the role of the Indo-Pacific Barrier as a genetic break, enhanced during periods of sea level decrease associated with a rare but continuous flow of hatchlings and young juveniles from Western Australia.
Abstract.
Casale P, Freggi D, Furii G, Vallini C, Salvemini P, Deflorio M, Totaro G, Raimondi S, Fortuna C, Godley BJ, et al (2014). Annual survival probabilities of juvenile loggerhead sea turtles indicate high anthropogenic impact on Mediterranean populations.
Aquatic Conservation: Marine and Freshwater EcosystemsAbstract:
Annual survival probabilities of juvenile loggerhead sea turtles indicate high anthropogenic impact on Mediterranean populations
One of the major gaps in the knowledge of sea turtle population dynamics is survival probability, in particular of juveniles, which represent the bulk of the population and whose survival has the greatest effect on population growth. One of the major global threats to sea turtles is incidental bycatch, although not all animals die in the process. This is particularly acute for the loggerhead sea turtle (Caretta caretta). Here fisheries-dependent monitoring is used to seek insights into patterns of survival at multiple Mediterranean foraging areas: north and south Adriatic, north Ionian, and the Tunisian shelf. Annual survival probability was estimated using the catch curve method. Size data of 2191 loggerhead turtles ranging from 19 to 92cm curved carapace length were converted to age according to eight age-size curves available from the Mediterranean Sea. The mean annual survival probabilities for the four areas were heterogeneous and ranged between 0.710 and 0.862. Results suggest that the survival probabilities for Mediterranean loggerheads, especially in some areas, are lower than would be expected from a healthy population. This is of particular concern for the Greek rookeries, which appear most affected by anthropogenic mortality occurring in the study areas. This supports the implementation in those areas of measures mitigating the main threats, notably bycatch. © 2014 John Wiley & Sons, Ltd.
Abstract.
Revuelta O, León YM, Broderick AC, Feliz P, Godley BJ, Balbuena JA, Mason A, Poulton K, Savoré S, Raga JA, et al (2014). Assessing the efficacy of direct conservation interventions: clutch protection of the leatherback marine turtle in the Dominican Republic.
ORYXAbstract:
Assessing the efficacy of direct conservation interventions: clutch protection of the leatherback marine turtle in the Dominican Republic
The beaches of Jaragua National Park in the Dominican Republic are the country's last known major nesting site for the leatherback marine turtle Dermochelys coriacea. This nesting aggregation is threatened by widespread illegal egg take, and clutch relocation and artificial incubation have been carried out as protection measures since 1974. We assess the efficacy of such efforts and investigate how artificial incubation may be influencing the success and sex ratios of clutches. We compare hatching success, incubation duration and embryo mortality in in-situ clutches (n = 43) with those incubated artificially at sites in the east and west of the Park (n = 35 and n = 31, respectively). Our results show that in the west, artificial incubation significantly decreases hatching success in clutches. In the east the duration of incubation is increased, which we predict would result in an increase in the number of males from these clutches. Clutch relocation is currently the only viable conservation option for clutches on eastern beaches because of illegal egg take but action is needed to ensure that the natural sex ratio is not distorted. However, on the western beaches in situ clutch incubation seems possible through beach protection. Further community engagement and enforcement are required to improve conservation measures at eastern beaches if long-term, less sustainable intervention is to be avoided. Copyright © Fauna & Flora International 2014.
Abstract.
Doherty PD, Alfaro-Shigueto J, Hodgson DJ, Mangel JC, Witt MJ, Godley BJ (2014). Big catch, little sharks: Insight into Peruvian small-scale longline fisheries.
Ecology and Evolution,
4(12), 2375-2383.
Abstract:
Big catch, little sharks: Insight into Peruvian small-scale longline fisheries
Shark take, driven by vast demand for meat and fins, is increasing. We set out to gain insights into the impact of small-scale longline fisheries in Peru. Onboard observers were used to document catch from 145 longline fishing trips (1668 fishing days) originating from Ilo, southern Peru. Fishing effort is divided into two seasons: targeting dolphinfish (Coryphaena hippurus; December to February) and sharks (March to November). A total of 16,610 sharks were observed caught, with 11,166 identified to species level. of these, 70.6% were blue sharks (Prionace glauca), 28.4% short-fin mako sharks (Isurus oxyrinchus), and 1% were other species (including thresher (Alopias vulpinus), hammerhead (Sphyrna zygaena), porbeagle (Lamnus nasus), and other Carcharhinidae species (Carcharhinus brachyurus, Carcharhinus falciformis, Galeorhinus galeus). Mean ± SD catch per unit effort of 33.6 ± 10.9 sharks per 1000 hooks was calculated for the shark season and 1.9 ± 3.1 sharks per 1000 hooks were caught in the dolphinfish season. An average of 83.7% of sharks caught (74.7% blue sharks; 93.3% mako sharks) were deemed sexually immature and under the legal minimum landing size, which for species exhibiting k-selected life history traits can result in susceptibility to over exploitation. As these growing fisheries operate along the entire Peruvian coast and may catch millions of sharks per annum, we conclude that their continued expansion, along with ineffective legislative approaches resulting in removal of immature individuals, has the potential to threaten the sustainability of the fishery, its target species, and ecosystem. There is a need for additional monitoring and research to inform novel management strategies for sharks while maintaining fisher livelihoods. © 2014 the Authors.
Abstract.
Pikesley SK, Godley BJ, Ranger S, Richardson PB, Witt MJ (2014). Cnidaria in UK coastal waters: Description of spatio-temporal patterns and inter-annual variability.
Journal of the Marine Biological Association of the United Kingdom,
94(7), 1401-1408.
Abstract:
Cnidaria in UK coastal waters: Description of spatio-temporal patterns and inter-annual variability
Concern has been expressed over future biogeographical expansion and habitat capitalization by species of the phylum Cnidaria, as this may have negative implications on human activities and ecosystems. There is, however, a paucity of knowledge and understanding of jellyfish ecology, in particular species distribution and seasonality. Recent studies in the UK have principally focused on the Celtic, Irish and North Seas, but all in isolation. In this study we analyse data from a publicly-driven sightings scheme across UK coastal waters (2003-2011; 9 years), with the aim of increasing knowledge on spatial and temporal patterns and trends. We describe inter-annual variability, seasonality and patterns of spatial distribution, and compare these with existing historic literature. Although incidentally-collected data lack quantification of effort, we suggest that with appropriate data management and interpretation, publicly-driven, citizen-science-based, recording schemes can provide for large-scale (spatial and temporal) coverage that would otherwise be logistically and financially unattainable. These schemes may also contribute to baseline data from which future changes in patterns or trends might be identified. We further suggest that findings from such schemes may be strengthened by the inclusion of some element of effort-corrected data collection.
Abstract.
Pikesley SK, Godley BJ, Ranger S, Richardson PB, Witt MJ (2014). Cnidaria in UK coastal waters: description of spatio-temporal patterns and inter-annual variability. The Journal of the Marine Biological Association of the United Kingdom
Hammerschlag N, Cooke SJ, Gallagher AJ, Godley BJ (2014). Considering the fate of electronic tags: Interactions with stakeholders and user responsibility when encountering tagged aquatic animals.
Methods in Ecology and Evolution,
5(11), 1147-1153.
Abstract:
Considering the fate of electronic tags: Interactions with stakeholders and user responsibility when encountering tagged aquatic animals
The use of electronic tagging (e.g. acoustic, archival and satellite telemetry) to study the behavior and ecology of aquatic animals has increased dramatically over the past decade. As scientists continue to use these tools, it is inevitable that other researchers and the public at-large will encounter animals carrying such tags with increasing frequency. If the animals appear burdened or injured by the tag (e.g. showing signs of trauma), or if the tag is functionally impaired (e.g. cracked or severely biofouled), these encounters have the potential to generate conflict with various wildlife stakeholders (e.g. tourists/operators, divers, fishers, hunters) that can negatively affect research efforts and undermine conservation work. Yet, these encounters also present an unparalleled opportunity to advance the field of biotelemetry by improving animal welfare, tagging technology and practices, while also gaining the trust and support of wildlife stakeholders. Therefore, as scientists, it is important to consider the fate of our electronic tags. Here we consider tagged animals as encountered by different user groups and discuss the potential steps and recommendations that scientists can take to improve tagging techniques and animal welfare as a result. We also discuss interactions with stakeholders and the manifold benefits if such interactions are taken into account and embraced. We examine the situation where a researcher encounters, and is able and trained to handle a previously tagged animal equipped with a functionally impaired tag and/or the animal is exhibiting signs of burden due to the tag. We generate a decision tree for scientists faced with such a scenario and discuss the best course of action, whereas such a situation was relatively unlikely in the past, but is now a reality in all aquatic animal tagging studies. The framework in which these issues are discussed is novel and failure to address them can significantly impede advances in the development and use of biotelemetry and even one's ability to conduct research. It is our hope that our essay stimulates further discourse, debate, technological improvements and consideration of the fate of electronic tagging.
Abstract.
Carreras C, Godley BJ, León YM, Hawkes LA, Revuelta O, Raga JA, Tomás J (2014). Correction: Contextualising the Last Survivors: Population Structure of Marine Turtles in the Dominican Republic. PLoS ONE, 9(1).
Stokes KL, Fuller WJ, Glen F, Godley BJ, Hodgson DJ, Rhodes KA, Snape RTE, Broderick AC (2014). Detecting green shoots of recovery: the importance of long-term individual-based monitoring of marine turtles.
Animal Conservation,
17(6), 593-602.
Abstract:
Detecting green shoots of recovery: the importance of long-term individual-based monitoring of marine turtles
Population monitoring is an essential part of evaluating the effectiveness of management interventions for conservation. Coastal breeding aggregations of marine vertebrate species that come ashore to pup or nest provide an opportunistic window of observation into otherwise widely dispersed populations. Green turtle (Chelonia mydas) nesting on the north and west coasts of northern Cyprus has been monitored consistently and exhaustively since 1993, with an intensive saturation tagging programme running at one key site for the same duration. This historically depleted nesting population is showing signs of recovery, possibly in response to nest protection approaching two decades, with increasing nest numbers and rising levels of recruitment. Strong correlation between year-to-year magnitude of nesting and the proportion of new breeders in the nesting cohort implies that recruitment of new individuals to the breeding population is an important driver of this recovery trend. Recent changes in fishing activities may be impacting the local juvenile neritic stage, however, which may hinder this potential recovery. Individuals returning to breed after two years laid fewer clutches than those returning after three or four years, demonstrating a trade-off between remigration interval and breeding output. Average clutch frequencies have remained stable around a median of three clutches a year per female despite the demographic shift towards new nesters, which typically lay fewer clutches in their first season. We show that where local fecundity has been adequately assessed, the use of average clutch frequencies can be a reliable method for deriving nester abundance from nest counts. Index sites where individual-based monitoring is possible will be important in monitoring long-term climate driven changes in reproductive rates.
Abstract.
Donnelly MA, Karsten KB, Pauers MJ, Shaffer HB, Kingsbury BA, Reading CJ, Green DM, Salcedo NJ, Trauth SE, Lowe MR, et al (2014). Divergent evolution in the polymorphic granular poison-dart frog, Oophaga granulifera: genetics, coloration, advertisement calls, and morphology. Ichthyology & Herpetology, 2014(1), 181-195.
Hawkes LA, Mcgowan A, Broderick AC, Gore S, Wheatley D, White J, Witt MJ, Godley BJ (2014). High rates of growth recorded for hawksbill sea turtles in Anegada, British Virgin Islands.
Ecology and Evolution,
4(8), 1255-1266.
Abstract:
High rates of growth recorded for hawksbill sea turtles in Anegada, British Virgin Islands
Management of species of conservation concern requires knowledge of demographic parameters, such as rates of recruitment, survival, and growth. In the Caribbean, hawksbill turtles (Eretmochelys imbricata) have been historically exploited in huge numbers to satisfy trade in their shells and meat. In the present study, we estimated growth rate of juvenile hawksbill turtles around Anegada, British Virgin Islands, using capture-mark-recapture of 59 turtles over periods of up to 649 days. Turtles were recaptured up to six times, having moved up to 5.9 km from the release location. Across all sizes, turtles grew at an average rate of 9.3 cm year-1 (range 2.3-20.3 cm year-1), and gained mass at an average of 3.9 kg year-1 (range 850 g-16.1 kg year-1). Carapace length was a significant predictor of growth rate and mass gain, but there was no relationship between either variable and sea surface temperature. These are among the fastest rates of growth reported for this species, with seven turtles growing at a rate that would increase their body size by more than half per year (51-69% increase in body length). This study also demonstrates the importance of shallow water reef systems for the developmental habitat for juvenile hawksbill turtles. Although growth rates for posthatching turtles in the pelagic, and turtles larger than 61 cm, are not known for this population, the implications of this study are that Caribbean hawksbill turtles in some areas may reach body sizes suggesting sexual maturity in less time than previously considered. In the present study, we estimated growth rate of juvenile hawksbill turtles around Anegada, British Virgin Islands, using capture-mark-recapture of 59 turtles over periods of up to 649 days. Across all sizes, turtles grew at an average rate of 9.3 cm per year (range 2.3-20.3 cm year-1), and gained mass at an average of 3.9 kg year-1 (range 850 g-16.1 kg year-1). These are among the fastest rates of growth reported for this species, with seven turtles growing at a rate that would increase their body size by more than half per year (51-69% increase in body length). © 2014 the Authors. Ecology and Evolution published by John Wiley & Sons Ltd.
Abstract.
Colman LP, Patrício ARC, McGowan A, Santos AJB, Marcovaldi MÂ, Bellini C, Godley BJ (2014). Long-term growth and survival dynamics of green turtles (Chelonia mydas) at an isolated tropical archipelago in Brazil. Marine Biology
Carreras C, Rees AF, Broderick AC, Godley BJ, Margaritoulis D (2014). Mitochondrial DNA markers of loggerhead marine turtles (Caretta caretta) (Testudines: Cheloniidae) nesting at Kyparissia Bay, Greece, confirm the western Greece unit and regional structuring.
Scientia Marina,
78(1), 115-124.
Abstract:
Mitochondrial DNA markers of loggerhead marine turtles (Caretta caretta) (Testudines: Cheloniidae) nesting at Kyparissia Bay, Greece, confirm the western Greece unit and regional structuring
Genetic markers have been widely used in marine turtles to assess population structuring and origin of individuals in common feeding grounds, which are key elements for understanding their ecology and for developing conservation strategies. However, these analyses are very sensitive to missing information, especially from abundant nesting sites. Kyparissia Bay (western Greece) hosts the second largest Mediterranean nesting aggregation of the loggerhead turtle (Caretta caretta), but the genetic profile of this nesting site has not, as yet, been described using the extended version of the historically used mitochondrial DNA (mtDNA) marker. This marker was genotyped for 36 individuals nesting at Kyparissia Bay and haplotype frequencies obtained were compared with published data from other Mediterranean nesting sites. The results confirmed the connection between Kyparissia and other western Greek nesting sites and the isolation of this western Greek group from other Mediterranean nesting areas. As a consequence of this isolation, this abundant group of nesting aggregations (almost 30% of the Mediterranean stock) is not likely to significantly contribute to the recovery of other declining Mediterranean units. © 2014 CSIC.
Abstract.
Carreras C, Rees AF, Broderick AC, Godley BJ, Margaritoulis D (2014). Mitochondrial DNA markers of loggerhead marine turtles (Caretta caretta) (Testudines: Cheloniidae) nesting at Kyparissia Bay, Greece, confirm the western Greece unit and regional structuring.
SCIENTIA MARINA,
78(1), 115-124.
Author URL.
Pikesley SK, Broderick AC, Cejudo D, Coyne MS, Godfrey MH, Godley BJ, Lopez P, López-Jurado LF, Elsy Merino S, Varo-Cruz N, et al (2014). Modelling the niche for a marine vertebrate: a case study incorporating behavioural plasticity, proximate threats and climate change. Ecography
Putman NF, Abreu-Grobois FA, Broderick AC, Ciofi C, Formia A, Godley BJ, Stroud S, Pelembe T, Verley P, Williams N, et al (2014). Numerical dispersal simulations and genetics help explain the origin of hawksbill sea turtles in Ascension Island.
Journal of Experimental Marine Biology and Ecology,
450, 98-108.
Abstract:
Numerical dispersal simulations and genetics help explain the origin of hawksbill sea turtles in Ascension Island
Long-distance dispersal and ontogenetic shifts in habitat use are characteristic of numerous marine species and have important ecological, evolutionary, and management implications. These processes, however, are often challenging to study due to the vast areas involved. We used genetic markers and simulations of physical transport within an ocean circulation model to gain understanding into the origin of juvenile hawksbill sea turtles (. Eretmochelys imbricata) found at Ascension Island, a foraging ground that is thousands of kilometers from known nesting beaches. Regional origin of genetic markers suggests that turtles are from Western Atlantic (86%) and Eastern Atlantic (14%) rookeries. In contrast, numerical simulations of transport by ocean currents suggest that passive dispersal from the western sources would be negligible and instead would primarily be from the East, involving rookeries along Western Africa (i.e. Principe Island) and, potentially, from as far as the Indian Ocean (e.g. Mayotte and the Seychelles). Given that genetic analysis identified the presence of a haplotype endemic to Brazilian hawksbill rookeries at Ascension, we examined the possible role of swimming behavior by juvenile hawksbills from NE Brazil on their current-borne transport to Ascension Island by performing numerical experiments in which swimming behavior was simulated for virtual particles (simulated turtles). We found that oriented swimming substantially influenced the distribution of particles, greatly altering the proportion of particles dispersing into the North Atlantic and South Atlantic. Assigning location-dependent orientation behavior to particles allowed them to reach Ascension Island, remain in favorable temperatures, encounter productive foraging areas, and return to the vicinity of their natal site. The age at first arrival to Ascension (4.5-5.5. years) of these particles corresponded well to estimates of hawksbill age based on their size. Our findings suggest that ocean currents and swimming behavior play an important role in the oceanic ecology of sea turtles and other marine animals. © 2013 Elsevier B.V.
Abstract.
Fossette S, Witt MJ, Miller P, Nalovic MA, Albareda D, Almeida AP, Broderick AC, Chacón-Chaverri D, Coyne MS, Domingo A, et al (2014). Pan-atlantic analysis of the overlap of a highly migratory species, the leatherback turtle, with pelagic longline fisheries.
Proc Biol Sci,
281(1780).
Abstract:
Pan-atlantic analysis of the overlap of a highly migratory species, the leatherback turtle, with pelagic longline fisheries.
Large oceanic migrants play important roles in ecosystems, yet many species are of conservation concern as a result of anthropogenic threats, of which incidental capture by fisheries is frequently identified. The last large populations of the leatherback turtle, Dermochelys coriacea, occur in the Atlantic Ocean, but interactions with industrial fisheries could jeopardize recent positive population trends, making bycatch mitigation a priority. Here, we perform the first pan-Atlantic analysis of spatio-temporal distribution of the leatherback turtle and ascertain overlap with longline fishing effort. Data suggest that the Atlantic probably consists of two regional management units: northern and southern (the latter including turtles breeding in South Africa). Although turtles and fisheries show highly diverse distributions, we highlight nine areas of high susceptibility to potential bycatch (four in the northern Atlantic and five in the southern/equatorial Atlantic) that are worthy of further targeted investigation and mitigation. These are reinforced by reports of leatherback bycatch at eight of these sites. International collaborative efforts are needed, especially from nations hosting regions where susceptibility to bycatch is likely to be high within their exclusive economic zone (northern Atlantic: Cape Verde, Gambia, Guinea Bissau, Mauritania, Senegal, Spain, USA and Western Sahara; southern Atlantic: Angola, Brazil, Namibia and UK) and from nations fishing in these high-susceptibility areas, including those located in international waters.
Abstract.
Author URL.
Weber SB, Weber N, Ellick J, Avery A, Frauenstein R, Godley BJ, Sim J, Williams N, Broderick AC (2014). Recovery of the South Atlantic's largest green turtle nesting population.
BIODIVERSITY AND CONSERVATION,
23(12), 3005-3018.
Author URL.
Maclean IM, Inger R, Booth CG, Embling CB, Grecian WJ, Heymans JJ, Plummer K, Shackshaft M, Sparling C, Wilson B, et al (2014). Resolving issues with environmental impact assessment of marine renewable energy installations. Frontiers in Marine Science, 1(75).
Humber F, Godley BJ, Broderick AC (2014). So excellent a fishe: a global overview of legal marine turtle fisheries. Diversity and Distributions
Humber F, Godley BJ, Broderick AC (2014). So excellent a fishe: a global overview of legal marine turtle fisheries.
Diversity and Distributions,
20(5), 579-590.
Abstract:
So excellent a fishe: a global overview of legal marine turtle fisheries
Aim: We provide a global assessment of the current legal direct take of marine turtles, including the scale and species breakdown at country level, and investigate the significance of legal take to marine turtle populations within the wider context of global threats. Location: World-wide. Methods: We undertook a comprehensive review of the literature (>500 publications) and contacted over 150 in-country experts to collate data for countries that permit the legal take of marine turtles (as of 1 January 2013). Current annual take for each country and species was estimated, and estimates were generated for the 1980s, 1990s and 2000s. Results: Currently, 42 countries and territories permit direct take of turtles and collectively take in excess of 42,000turtles per year, the majority of which (>80%) are green turtles Chelonia mydas (Linnaeus 1758). Ten countries account for more than 90% of legal take each year with Papua New Guinea (36.1%) and Nicaragua (22.3%) accounting for more than half of the total global take. Since 1980, we estimate that more than 2million turtles have been legally taken in these countries, with current levels
Abstract.
Horne CR, Fuller WJ, Godley BJ, Rhodes KA, Snape R, Stokes KL, Broderick AC (2014). The effect of thermal variance on the phenotype of marine turtle offspring.
Physiol Biochem Zool,
87(6), 796-804.
Abstract:
The effect of thermal variance on the phenotype of marine turtle offspring.
Temperature can have a profound effect on the phenotype of reptilian offspring, yet the bulk of current research considers the effects of constant incubation temperatures on offspring morphology, with few studies examining the natural thermal variance that occurs in the wild. Over two consecutive nesting seasons, we placed temperature data loggers in 57 naturally incubating clutches of loggerhead sea turtles Caretta caretta and found that greater diel thermal variance during incubation significantly reduced offspring mass, potentially reducing survival of hatchlings during their journey from the nest to offshore waters and beyond. With predicted scenarios of climate change, behavioral plasticity in nest site selection may be key for the survival of ectothermic species, particularly those with temperature-dependent sex determination.
Abstract.
Author URL.
Revuelta O, León YM, Balbuena JA, Broderick AC, Feliz P, Godley BJ, Raga JA, Tomás J (2014). The value of endangered species in protected areas at risk: the case of the leatherback turtle in the Dominican Republic.
Biodiversity and Conservation,
23(6), 1529-1539.
Abstract:
The value of endangered species in protected areas at risk: the case of the leatherback turtle in the Dominican Republic
Protected areas are considered essential elements for global biodiversity conservation. They may not necessarily result in an effective conservation of resources in developing countries due to lack of funding for management and enforcement. In addition, poor governance aligned with conflicts of economic interests related to their use can further threaten their integrity and persistence. In the Dominican Republic, the western beaches of the Jaragua National Park (JNP), a protected area which is also part of a UNESCO Biosphere Reserve, have been proposed for development using a mass-tourism model. One of the most charismatic species found in this area is the leatherback turtle (Dermochelys coriacea). In the present study, we assess hatching success, and factors affecting it, to determine the reproductive value across the area for the leatherback turtle. The main factors found driving hatching success at the study beaches are beach sector, incubation duration, date of lay and clutch size. Our results show that clutches in La Cueva (located in the buffer zone of the park) and Bahía de las Águilas (located inside the limits of the park) have an unusually high hatching success (~75 %) for this species, highlighting the importance of increasing protection efforts at these sites. We strongly recommend including La Cueva inside the limits of the JNP. © 2014 Springer Science+Business Media Dordrecht.
Abstract.
Revuelta O, León YM, Balbuena JA, Broderick AC, Feliz P, Godley BJ, Raga JA, Tomás J (2014). The value of endangered species in protected areas at risk: the case of the leatherback turtle in the Dominican Republic. Biodiversity and Conservation
McClellan CM, Brereton T, Dell'Amico F, Johns DG, Cucknell A-C, Patrick SC, Penrose R, Ridoux V, Solandt J-L, Stephan E, et al (2014). Understanding the distribution of marine megafauna in the English channel region: identifying key habitats for conservation within the busiest seaway on earth.
PLoS One,
9(2).
Abstract:
Understanding the distribution of marine megafauna in the English channel region: identifying key habitats for conservation within the busiest seaway on earth.
The temperate waters of the North-Eastern Atlantic have a long history of maritime resource richness and, as a result, the European Union is endeavouring to maintain regional productivity and biodiversity. At the intersection of these aims lies potential conflict, signalling the need for integrated, cross-border management approaches. This paper focuses on the marine megafauna of the region. This guild of consumers was formerly abundant, but is now depleted and protected under various national and international legislative structures. We present a meta-analysis of available megafauna datasets using presence-only distribution models to characterise suitable habitat and identify spatially-important regions within the English Channel and southern bight of the North Sea. The integration of studies from dedicated and opportunistic observer programmes in the United Kingdom and France provide a valuable perspective on the spatial and seasonal distribution of various taxonomic groups, including large pelagic fishes and sharks, marine mammals, seabirds and marine turtles. The Western English Channel emerged as a hotspot of biodiversity for megafauna, while species richness was low in the Eastern English Channel. Spatial conservation planning is complicated by the highly mobile nature of marine megafauna, however they are important components of the marine environment and understanding their distribution is a first crucial step toward their inclusion into marine ecosystem management.
Abstract.
Author URL.
Carreras C, Godley BJ, León YM, Hawkes LA, Revuelta O, Raga JA, Tomás J (2013). Contextualising the Last Survivors: Population Structure of Marine Turtles in the Dominican Republic.
PLoS ONE,
8(6).
Abstract:
Contextualising the Last Survivors: Population Structure of Marine Turtles in the Dominican Republic
Nesting by three species of marine turtles persists in the Dominican Republic, despite historic threats and long-term population decline. We conducted a genetic survey of marine turtles in the Dominican Republic in order to link them with other rookeries around the Caribbean. We sequenced a 740bp fragment of the control region of the mitochondrial DNA of 92 samples from three marine turtle species [hawksbill (n = 48), green (n = 2) and leatherback (n = 42)], and incorporated published data from other nesting populations and foraging grounds. The leatherback turtle (Dermochelys coriacea) in the Dominican Republic appeared to be isolated from Awala-Yalimapo, Cayenne, Trinidad and St. Croix but connected with other Caribbean populations. Two distinct nesting populations of hawksbill turtles (Eremochelys imbricata) were detected in the Dominican Republic and exhibited interesting patterns of connectivity with other nesting sites and juvenile and adult male foraging aggregations. The green sea turtle (Chelonia mydas) has almost been extirpated from the Dominican Republic and limited inference could be made from our samples. Finally, results were compared with Lagrangian drifting buoys and published Lagrangian virtual particles that travelled through the Dominican Republic and Caribbean waters. Conservation implications of sink-source effects or genetic isolation derived from these complex inter-connections are discussed for each species and population. © 2013 Carreras et al.
Abstract.
Rees AF, Margaritoulis D, Newman R, Riggall TE, Tsaros P, Zbinden JA, Godley BJ (2013). Ecology of loggerhead marine turtles Caretta caretta in a neritic foraging habitat: Movements, sex ratios and growth rates.
Marine Biology,
160(3), 519-529.
Abstract:
Ecology of loggerhead marine turtles Caretta caretta in a neritic foraging habitat: Movements, sex ratios and growth rates
Much is still to be learned about the spatial ecology of foraging marine turtles, especially for juveniles and adult males which have received comparatively little attention. Additionally, there is a paucity of ecological information on growth rates, size and age at maturity, and sex ratios at different life stages; data vital for successful population modelling. Here, we present results of a long-term (2002-2011) study on the movements, residency, growth and sex ratio of loggerhead turtles (Caretta caretta) in Amvrakikos Gulf (39°0′N 21°0′E), Greece, using satellite telemetry (N = 8) and ongoing capture-mark-recapture (CMR; N = 300 individuals). Individuals encountered at sea ranged from large juvenile to adult (46. 2-91. 5 cm straight carapace length) and demonstrated growth rates within published norms (44 % of captures above 65 cm straight carapace length), compared to region-wide female-biased hatchling production, indicating sex-biased survival or possible behavioural drivers for likelihood of capture in the region. Satellite tracking confirmed that some turtles establish discrete, protracted periods of residency spanning more than 1 year, whilst others migrated away from the site. These findings are underlined by CMR results with individual capture histories spanning up to 7 years, and only 18 % of individuals being recaptured. © 2012 Springer-Verlag Berlin Heidelberg.
Abstract.
Hawkes LA, McGowan A, Godley BJ, Gore S, Lange A, Tyler CR, Wheatley D, White J, Witt MJ, Broderick AC, et al (2013). Estimating sex ratios in Caribbean hawksbill turtles: Testosterone levels and climate effects.
Aquatic Biology,
18(1), 9-19.
Abstract:
Estimating sex ratios in Caribbean hawksbill turtles: Testosterone levels and climate effects
Evolutionary theory predicts that male and female offspring should be produced at a 1:1 ratio, but this may rarely be the case for species in which sex is determined during incubation by temperature, such as marine turtles. Estimates of primary sex ratio suggest that marine turtle sex ratios are highly skewed, with up to 9 females per male. We captured juvenile hawksbill turtles Eretmochelys imbricata in waters around Anegada, British Virgin Islands, a regionally important foraging aggregation, and analysed concentrations of plasma testosterone and oestradiol- 17β from 62 turtles to estimate sex ratio. There were 2.4 to 7.7 times more females than males. Testosterone concentrations correlated with sampling date and sea surface temperature (SST), with higher con centrations in the late summer when SST was highest, suggesting that assigning sex through threshold values of sex hormones must be carried out cautiously. The sex ratio in the juvenile foraging aggregation around Anegada is more male biased than at other locations, suggesting that turtles at Anegada have resilience against feminising effects of climate change. Future work should (1) integrate the relative contributions of different genetic stocks to foraging aggregations and (2) investigate the annual and seasonal cycles of sex hormones, and differences among individuals and life history stages. © Inter-Research 2013.
Abstract.
Griffin DBB, Murphy SR, Frick MG, Broderick AC, Coker JW, Coyne MS, Dodd MG, Godfrey MH, Godley BJ, Hawkes LA, et al (2013). Foraging habitats and migration corridors utilized by a recovering subpopulation of adult female loggerhead sea turtles: Implications for conservation.
Marine Biology,
160(12), 3071-3086.
Abstract:
Foraging habitats and migration corridors utilized by a recovering subpopulation of adult female loggerhead sea turtles: Implications for conservation
From 1998 to 2008, 68 adult female loggerhead sea turtles (Caretta caretta) were instrumented with platform transmitter terminals at nesting beaches in Georgia, North Carolina (NC) and South Carolina (SC) on the East Coast of the United States of America (30°48′N, 81°28′W to 33°51′N, 77°59′W). The majority of post-nesting loggerheads (N = 42, 62 %) migrated to foraging habitats in the Mid-Atlantic Bight during May-October, with a subsequent migration occurring during November-March to foraging habitats south of Cape Hatteras, NC. Nine (13 %) loggerheads initially foraged in the near-shore, coastal areas of the South Atlantic Bight, but moved to offshore habitats-closer to the Gulf Stream-during November-March, while fourteen (21 %) loggerheads remained in foraging areas along the mid-continental shelf off of the eastern coast of Florida and/or continued southward to Florida Bay and the Bahamas. The present study delineates important, post-nesting foraging habitats and migration corridors where loggerheads may interact with commercial fisheries-providing managers opportunities to develop and implement optimally effective conservation actions for the recovery of this threatened species. © 2013 Springer-Verlag Berlin Heidelberg.
Abstract.
Griffin DB, Murphy SR, Frick MG, Broderick AC, Coker JW, Coyne MS, Dodd MG, Godfrey MH, Godley BJ, Hawkes LA, et al (2013). Foraging habitats and migration corridors utilized by a recovering subpopulation of adult female loggerhead sea turtles: implications for conservation. Marine Biology, 1-16.
Rees AF, Hafez AA, Lloyd JR, Papathansopoulou N, Godley BJ (2013). Green turtles, chelonia mydas, in Kuwait: Nesting and movements.
Chelonian Conservation and Biology,
12(1), 157-163.
Abstract:
Green turtles, chelonia mydas, in Kuwait: Nesting and movements
There is a paucity of information on the presence and nesting of green turtles, Chelonia mydas, in Kuwait, and known nesting habitats have been altered in recent years. Through beach monitoring and satellite telemetry, we determined that green turtle nesting is now limited to Qaru Island with 1-5 turtles nesting annually and that foraging habitats occur along the northern shore of Failaka Island (n=2 turtles) and coastal region of central Saudi Arabia (n=1 turtle). Foraging habitat in Kuwait overlaps with a coastal trap-fishery, raising concerns for the conservation of this depleted population. © 2013 Chelonian Research Foundation.
Abstract.
King C, Lomolino M, Roemer G, Godley B (2013). Habitat case studies: islands.
, 204-221.
Abstract:
Habitat case studies: islands
Many important issues in conservation biology are more clearly visible on islands than on continental mainlands. This chapter summarizes a few of the key topics that concern island managers worldwide, with exemplary habitat case studies from the islands. The chapter considers primarily the land-breeding vertebrate faunas of islands, but only because there are fewer consistent and comparable databases available on plants and invertebrates. Insular species are ecologically naive to exotic competitors, predators and parasites, or imperilled by the loss of native pollinators, seed dispersers and other mutualists. In order to conserve the marvellous diversity and the natural characters of island biota, the challenge is to manage fragile, insular assemblages successfully. That means attempting to minimize intense habitat destruction and alteration, such as logging, agricultural conversion and urbanization, and reducing the threat from ecologically novel, exotic species while maintaining or replacing natural, ecological conditions that shaped the evolution of island life. © 2013 John Wiley & Sons, Ltd.
Abstract.
Pikesley SK, Agamboue PD, Bonguno EA, Boussamba F, Cardiec F, Michael Fay J, Formia A, Godley BJ, Laurance WF, Mabert BDK, et al (2013). Here today, here tomorrow: Beached timber in Gabon, a persistent threat to nesting sea turtles. Biological Conservation
Fuller WJ, Godley BJ, Hodgson DJ, Reece SE, Witt MJ, Broderick AC (2013). Importance of spatio-temporal data for predicting the effects of climate change on marine turtle sex ratios.
Marine Ecology Progress Series,
488, 267-274.
Abstract:
Importance of spatio-temporal data for predicting the effects of climate change on marine turtle sex ratios
Species with temperature-dependent sex determination (TSD) are likely to be impacted by climate change. There is a paucity of data on the contemporary sex ratios of offspring produced by regional marine turtle populations. The lack of such information inhibits the ability of researchers to accurately predict how future meteorological and climate-driven changes may affect turtle populations. Moreover, these data are integral for the development of regional and global recovery plans for declining turtle populations. We estimate offspring sex ratios for the loggerhead turtle Caretta caretta at a range of beaches on the Mediterranean island of Cyprus over a 10 yr period (1997 to 2006; 40 beaches, 628 clutches, 29402 hatchlings). Based on hatchling sex determination, we found the pivotal incubation temperature (the temperature at which a 50:50 sex ratio occurs) to be 28.9°C, and the pivotal incubation duration to be 56.3 d. From the incubation durations of over 628 in situ clutches laid on different beaches, we estimate that 89% of the offspring produced from these clutches were female. There was, however, both inter-annual (74 to 95% female) and inter-beach (58-98% female) variability in mean offspring sex ratios. These findings highlight the need for wide-scale, long-term monitoring of primary sex ratios in order to accurately predict the likely impacts of climate change. Despite spatial and temporal variation in offspring sex ratios produced, male hatchlings are certainly in the minority in Cyprus. It is therefore highly likely that beaches producing males will become increasingly critical habitats for successful clutch incubation in the face of predicted rising temperatures. © Inter-Research 2013.
Abstract.
Mills CA, Dawson DA, Horsburgh GJ, Godley BJ, Hodgson DJ (2013). Isolation and characterisation of hazel dormouse (Muscardinus avellanarius) microsatellite loci.
Conservation Genetics Resources,
5(3), 687-692.
Abstract:
Isolation and characterisation of hazel dormouse (Muscardinus avellanarius) microsatellite loci
Hazel dormice, Muscardinus avellanarius (Rodentia: Gliridae) are vulnerable to habitat loss and fragmentation, and thus protected by European Directives. We isolated hazel dormouse microsatellite sequences from enriched genomic libraries to facilitate conservation-focussed research, such as population genetics, regarding this threatened species. Fifty-three primer sets were designed from 51 newly isolated loci. Additionally, we redesigned and tested nine primer sets from previously-published hazel dormouse microsatellite sequences. These 62 marker sets were initially tested in eight unrelated individuals. Thirty-nine loci, which were polymorphic and amplified in >88 % of these samples (extracted from hair), were then genotyped and characterised in 22-26 individuals. of these, 26 autosomal loci (18 new and eight published) adhered to Hardy-Weinberg equilibrium (p ≤ 0.05) and displayed an estimated null allele frequency of
Abstract.
Richardson PB, Broderick AC, Coyne MS, Gore S, Gumbs JC, Pickering A, Ranger S, Witt MJ, Godley BJ (2013). Leatherback turtle conservation in the Caribbean UK overseas territories: Act local, think global?.
Marine Policy,
38, 483-490.
Abstract:
Leatherback turtle conservation in the Caribbean UK overseas territories: Act local, think global?
Leatherback turtles migrate across the jurisdictions of multiple sovereign states and present complex challenges to those responsible for their conservation. Concern for marine turtles has led to their protection under range state legislation and protective listing under a suite of multilateral environmental agreements. Evidence suggests that a distinct, reproductive sub-population of leatherback turtles is shared amongst a number of northern Caribbean range states, including the UK overseas territories (UKOTs) of Anguilla and the British Virgin Islands (BVI). The post-nesting movements of three female leatherbacks were tracked after they nested in Anguilla (n=1, tracked for 228 days) and the BVI (n=2, tracked for 12 and 13 days, respectively). These turtles used territories of multiple range states, with the leatherback tracked from Anguilla also migrating through high seas to foraging grounds in Canadian waters. In addition, a review of regional leatherback flipper tag return records helps define the range of this northern Caribbean nesting population (NCNP), which appears to be in recovery in some range states. While national legislation and conservation efforts appear to have contributed to these population recoveries, most relevant MEAs appear to have played little or no role. However, opportunities for constructive dialogue between NCNP range states exist under the Cartagena Convention the United Nations Convention on the Law of the Sea and the International Commission for the Conservation of Atlantic Tuna (ICCAT). UKOT conservation managers would, therefore, be justified in prioritising unilateral leatherback conservation action, and multilateral efforts through the Cartagena convention and regional fishery management mechanisms, over potentially costly accessions to additional MEAs.
Abstract.
Stringell TB, Calosso MC, Claydon JAB, Clerveaux W, Godley BJ, Lockhart KJ, Phillips Q, Ranger S, Richardson PB, Sanghera A, et al (2013). Marine turtle harvest in a mixed small-scale fishery: Evidence for revised management measures.
Ocean and Coastal Management,
82, 34-42.
Abstract:
Marine turtle harvest in a mixed small-scale fishery: Evidence for revised management measures
Small-scale fisheries (SSF) account for around half of the world's marine and inland fisheries, but their impact on the marine environment is usually under-estimated owing to difficulties in monitoring and regulation. Successful management of mixed SSF requires holistic approaches that sustainably exploit target species, consider non-target species and maintain fisher livelihoods. For two years, we studied the marine turtle fishery in the Turks and Caicos Islands (TCI) in the Wider Caribbean Region, where the main export fisheries are queen conch (Strombus gigas) and the spiny lobster (Panulirus argus); with fin-fish, green turtles (Chelonia mydas) and hawksbill turtles (Eretmochelys imbricata) taken for domestic consumption. We evaluate the turtle harvest in relation to the other fisheries and recommend legislation and management alternatives. We demonstrate the connectivity between multi-species fisheries and artisanal turtle capture: with increasing lobster catch-per-unit-effort (CPUE), hawksbill catch increased whilst green turtle catch decreased. With increasing conch CPUE, hawksbill catch declined and there was no demonstrable effect on green turtle catch. We estimate 176-324 green and 114-277 hawksbill turtles are harvested annually in TCI: the largest documented legal hawksbill fishery in the western Atlantic. of particular concern is the capture of adult turtles. Current legislation focuses take on larger individuals that are key to population maintenance. Considering these data we recommend the introduction of maximum size limits for both species and a closed season on hawksbill take during the lobster fishing season. Our results highlight the need to manage turtles as part of a broader approach to SSF management. © 2013 Elsevier Ltd.
Abstract.
Wright LI, Fuller WJ, Godley BJ, McGowan A, Tregenza T, Broderick AC (2013). No benefits of polyandry to female green turtles.
Behavioral Ecology,
24(4), 1022-1029.
Abstract:
No benefits of polyandry to female green turtles
Multiple paternity is extremely common in natural populations of almost all reptiles studied to date, suggesting that pay-offs from polyandrous mating systems are important in these taxonomic groups. However, strong evidence in support of direct or indirect benefits to females is scarce. We examined the relationship between polyandry and components of female reproductive success and offspring fitness in the promiscuous green turtle (Chelonia mydas), a species that exhibits highly variable levels of multiple paternity. We did not detect any clear fitness benefits to polyandrous females in this study, and we discuss the potential of sexual conflict to influence female mating patterns in marine turtles. We show that polyandrous females produce significantly smaller clutches than monandrous females, highlighting a potential cost to polyandry in green turtles. Furthermore, multiple paternity was more common in returning females (recorded breeding in a previous season) than in females nesting for the first time at our study site, possibly reflecting increased encounter rates with males or sperm storage across breeding seasons. Our results reveal potentially complex influences of female traits, environment, and mating strategy on components of reproductive success, and we discuss the challenges associated with unraveling the costs and benefits of multiple mating in natural populations. © 2013 the Author. Published by Oxford University Press on behalf of the International Society for Behavioral Ecology. All rights reserved.
Abstract.
Pikesley SK, Maxwell SM, Pendoley K, Costa DP, Coyne MS, Formia A, Godley BJ, Klein W, Makanga-Bahouna J, Maruca S, et al (2013). On the front line: Integrated habitat mapping for olive ridley sea turtles in the Southeast Atlantic.
Diversity and Distributions,
19(12), 1518-1530.
Abstract:
On the front line: Integrated habitat mapping for olive ridley sea turtles in the Southeast Atlantic
Aim: Knowledge and understanding of marine vertebrate spatial ecology are required to identify sources of threat and highlight areas for conservation. Olive ridley sea turtles Lepidochelys olivacea are in decline in some regions, and data for the Eastern Atlantic are sparse. Here, we seek to describe observed, and potential, post-nesting habitats for this species in the southeast Atlantic. We contextualize these with fisheries catch data to identify areas of potential threat from fisheries interaction for this species. Location: West coast of Africa, southeast Atlantic. Methods: We tracked 21 female olive ridley turtles, from two nesting sites, between 2007 and 2010. We used ensemble ecological niche modelling, integrated with knowledge on the physical and biological oceanographic environment, to identify regions where environmental variables exist that may be critical in defining post-nesting habitats for this species. We further integrate fisheries catch data to contextualize potential threat from fisheries. Results: We describe key areas of observed, and potential, olive ridley turtle occurrence at sea, and reveal that there was considerable overlap of these conspecifics, from two distinct nesting regions, within the Angolan exclusive economic zone (EEZ). With the inclusion of fisheries catch data for the region, we highlight areas that have the potential for conflict with fishing activities known to result in bycatch. Main conclusions: This study demonstrates that it is imperative that marine conservation policy recognizes the spatial extent of highly migratory species with expansive ranges. It also highlights that deficiencies exist in current knowledge of bycatch, both in gear specificity and in catch per unit effort. With integration of vessel monitoring system (VMS) data and those on fisheries catch, knowledge and understanding of bycatch may be improved, and this will ultimately facilitate development of appropriate management strategies and long-term sustainability of fisheries and their supporting ecosystems. © 2013 John Wiley & Sons Ltd.
Abstract.
Pikesley SK, Maxwell SM, Pendoley K, Costa DP, Coyne MS, Formia A, Godley BJ, Klein W, Makanga-Bahouna J, Maruca S, et al (2013). On the front line: integrated habitat mapping for olive ridley sea turtles in the southeast Atlantic. Diversity and Distributions, 19(12), 1518-1530.
Richardson PB, Broderick AC, Coyne MS, Ekanayake L, Kapurusinghe T, Premakumara C, Ranger S, Saman MM, Witt MJ, Godley BJ, et al (2013). Satellite telemetry reveals behavioural plasticity in a green turtle population nesting in Sri Lanka. Marine Biology, 1-12.
Richardson PB, Broderick AC, Coyne MS, Ekanayake L, Kapurusinghe T, Premakumara C, Ranger S, Saman MM, Witt MJ, Godley BJ, et al (2013). Satellite telemetry reveals behavioural plasticity in a green turtle population nesting in Sri Lanka.
Marine Biology,
160(6), 1415-1426.
Abstract:
Satellite telemetry reveals behavioural plasticity in a green turtle population nesting in Sri Lanka
Satellite transmitters were deployed on ten green turtles (Chelonia mydas) nesting in Rekawa Sanctuary (RS-80.851°E 6.045°N), Sri Lanka, during 2006 and 2007 to determine inter-nesting and migratory behaviours and foraging habitats. Nine turtles subsequently nested at RS and demonstrated two inter-nesting strategies linked to the location of their residence sites. Three turtles used local shallow coastal sites within 60 km of RS during some or all of their inter-nesting periods and then returned to and settled at these sites on completion of their breeding seasons. In contrast, five individuals spent inter-nesting periods proximate to RS and then migrated to and settled at distant (>350 km) shallow coastal residence sites. Another turtle also spent inter-nesting periods proximate to RS and then migrated to a distant oceanic atoll and made forays into oceanic waters for 42 days before transmissions ceased. This behavioural plasticity informs conservation management beyond protection at the nesting beach. © 2013 Springer-Verlag Berlin Heidelberg.
Abstract.
Varo-Cruz N, Hawkes LA, Cejudo D, López P, Coyne MS, Godley BJ, López-Jurado LF (2013). Satellite tracking derived insights into migration and foraging strategies of male loggerhead turtles in the eastern Atlantic.
Journal of Experimental Marine Biology and Ecology,
443, 134-140.
Abstract:
Satellite tracking derived insights into migration and foraging strategies of male loggerhead turtles in the eastern Atlantic
In recent years, information about the movements and timing of migration by male sea turtles has begun to be unraveled. Here, we present the first satellite tracking of male loggerhead sea turtles (Caretta caretta) in the eastern Atlantic. Satellite linked transmitters were attached to five adult males, captured in the near shore waters off Boavista, Republic of Cape Verde. This archipelago hosts the single most important breeding site of loggerhead turtles in the eastern Atlantic. Animals were tracked for periods ranging between 48 and 537. days, including a probable annual remigration to the vicinity of the nesting ground for one turtle. Males showed a variety of movement patterns both during and after the breeding season. of three males that transmitted for 85, 329 and 537. days, two (the smallest) migrated east and remained in oceanic waters for the tracking period and another (larger turtle) migrated 810. km northeast, to neritic waters off the coast of Mauritania, Western Africa. Results suggest males may show the same size-linked dichotomy in migratory strategies, as has been shown for females from this population. © 2013 Elsevier B.V.
Abstract.
Snape RTE, Beton D, Broderick AC, Çiçek BA, Fuller WJ, Özden O, Godley BJ (2013). Strand monitoring and anthropological surveys provide insight into marine turtle bycatch in small-scale fisheries of the Eastern Mediterranean.
Chelonian Conservation and Biology,
12(1), 44-55.
Abstract:
Strand monitoring and anthropological surveys provide insight into marine turtle bycatch in small-scale fisheries of the Eastern Mediterranean
It has become widely recognized that a large gap exists in the global knowledge of fisheries due to the continued oversight of the small-scale sector. For populations of marine turtles restricted to the eastern Mediterranean, bycatch in small-scale fisheries is a concern. By using North Cyprus as a case study for the region, we used anthropological methods to estimate the magnitude of marine turtle bycatch, while presenting novel information on the marine turtle life stages using the coast and profiling the fishery itself. Our analyses suggest that as many as 1000 turtles may be caught annually by this fishery with an estimated mortality rate of 60%. Trammel nets were the main cause of marine turtle bycatch. Strandings coincided with setting of trammel nets that target siganids (Siganus luridus and Siganus rivulatus) and the majority of bycatch registered by fishers were caught in these gear types. We demonstrate a relatively simple approach to evaluating marine turtle bycatch, providing information that will allow local authorities and conservation groups to direct further research and possible mitigation measures. © 2013 Chelonian Research Foundation.
Abstract.
Weber N, Weber SB, Godley BJ, Ellick J, Witt M, Broderick AC (2013). Telemetry as a tool for improving estimates of marine turtle abundance.
Biological Conservation,
167, 90-96.
Abstract:
Telemetry as a tool for improving estimates of marine turtle abundance
Accurate estimates of abundance are fundamental to the conservation of threatened species, but are often difficult to obtain directly. Population size assessments of marine turtles are often based on counts of nests, which are then related to abundance using the mean number of clutches laid by individuals within a season. Due to low re-encounter probabilities, clutch frequency has proven difficult to estimate reliably, particularly for large populations that make a major contribution to global stock assessments. We use a combination of VHF radio-telemetry and Argos-linked Fastloc™ GPS devices to improve clutch frequency estimates for one of the world's largest green turtle rookeries at Ascension Island. Females fitted with VHF tags at the start of the season (. n=. 40) were re-encountered with a probability of 85% and laid a minimum average of 5.8 clutches. Three of these turtles were fitted with VHF and GPS devices and using the data collected by the latter, were found to lay an average of 6.3 clutches. GPS-telemetry detected emergences observed using radio-telemetry, and confirmed that some radio-tagged turtles laid again after their last observed emergence. Correcting for missed nesting events yielded a mean clutch frequency of 6.3, more than doubling the previous estimate of 3.0 for this population. Applying this revised assessment to annual nest counts reduces the estimated size of this population by 52%. Conventional tagging approaches may considerably underestimate annual fecundity of turtles, resulting in inflated population size estimates. We call for urgent reassessment of baseline abundance values for regionally important populations. © 2013 Elsevier Ltd.
Abstract.
Mangel JC, Alfaro-Shigueto J, Witt MJ, Hodgson DJ, Godley BJ (2013). Using pingers to reduce bycatch of small cetaceans in Peru's small-scale driftnet fishery.
ORYX,
47(4), 595-606.
Abstract:
Using pingers to reduce bycatch of small cetaceans in Peru's small-scale driftnet fishery
There is growing awareness that small-scale fisheries may have large impacts on threatened marine fauna. Bycatch of small cetaceans by the Peruvian small-scale driftnet fleet results in the deaths of thousands of animals annually. We sought to assess the effectiveness of acoustic alarms (pingers) for reducing the incidental capture of dolphins and porpoises by this fleet. Forty-three experimental trips (156 fishing sets) and 47 control trips (195 fishing sets) out of Salaverry Port, northern Peru, were observed from April 2009 to August 2011. Twenty-two percent of control sets captured small cetaceans (67 individuals) and 16% of experimental sets had captures of small cetaceans (33 individuals). The bycatch rate of experimental sets was 0.50 individuals km-2h-1, whereas for control sets the rate was 0.80 individuals km-2h-1. This 37% reduction in bycatch rate suggests that pingers may be effective in reducing the bycatch of small cetaceans in this fishery. Catch rates of the fishery's target shark and ray species were unchanged. Given the vast size of this fishery and its current levels of bycatch of small cetaceans (>Â 10,000 individuals annually), even the modest declines in bycatch we observed could result in reductions in mortality of hundreds or thousands of small cetaceans per annum. Challenges, including increased costs, to large-scale utilization of pingers have yet to be overcome. The harpooning of dolphins for use as bait will also need to be addressed for further reductions in dolphin and porpoise bycatch and mortality to be achievable. © 2013 Fauna & Flora International.
Abstract.
Stipala J, Lutzmann N, Malonza PK, Wilkinson P, Godley B, Nyamache J, Evans MR (2012). A new species of chameleon (Squamata: Chamaeleonidae) from the Aberdare Mountains in the central highlands of Kenya.
Zootaxa(3391), 1-22.
Abstract:
A new species of chameleon (Squamata: Chamaeleonidae) from the Aberdare Mountains in the central highlands of Kenya
We describe a new species of chameleon, Trioceros kinangopensis sp. nov. from Kinangop Peak in the Aberdare mountains, central highlands of Kenya. The proposed new species is morphologically and genetically distinct from other member of the bitaeniatus-group. It is morphologically most similar to T. schubotzi but differs in the lack of sexual size dimorphism, smaller-sized females, smoother, less angular canthus rostrales, smaller scales on the temporal region and a bright orange gular crest in males. Mitochondrial DNA indicates that the proposed new taxon is a distinct lineage that is closely related to T. nyirit and T. schubotzi. The distribution of T. kinangopensis sp. nov. appears to be restricted to the afroalpine zone in vicintiy of Kinangop Peak and fires may pose a serious threat to the long-term survival of this species. Copyright © 2012 · Magnolia Press.
Abstract.
Grecian WJ, Attrill MJ, Votier SC, Witt MJ, Bearhop S, Godley BJ, Grémillet D, Grémillet D, Hamer KC (2012). A novel projection technique to identify important at-sea areas for seabird conservation: an example using Northern gannets breeding in the North East Atlantic.
Biological ConservationAbstract:
A novel projection technique to identify important at-sea areas for seabird conservation: an example using Northern gannets breeding in the North East Atlantic
Seabirds are well monitored and protected at their breeding grounds but spend most of their life at sea, where they are less well monitored and afforded little protection. In an attempt to address this dichotomy, attention has been directed toward establishing a network of marine reserves for seabirds, based largely on information from at-sea surveys and/or biotelemetry studies. Nevertheless, these approaches are costly, are typically only available for a limited number of locations, and not suitable for species that have either poor at-sea detectability or are unable to carry tracking devices. Here we develop a technique to identify important areas for breeding seabirds based on at-sea projections from colonies. Synthesising data from colony surveys with detailed information on population dynamics, foraging ecology and near-colony behaviour, we project colony-specific foraging distributions of the Northern gannet (Morus bassanus) at colonies in the UK, Ireland and France. We test the ability of our models to identify at-sea hotspots through comparison with existing data from biotelemetry studies and at-sea visual surveys. These models show a positive spatial correlation with one of the most intensive at-sea seabird survey datasets. While there are limitations to estimating at-sea distributions of seabirds, implemented appropriately, we propose they could prove useful in identifying potential Marine Protected Areas for seabirds. Moreover, these models could be developed to suit a range of species or whole communities and provide a theoretical framework for the study of factors such as colony size regulation. © 2012 Elsevier Ltd. All rights reserved.
Abstract.
Grecian WJ, Witt MJ, Attrill MJ, Bearhop S, Godley BJ, Grémillet D, Hamer KC, Votier SC (2012). A novel projection technique to identify important at-sea areas for seabird conservation: an example using Northern gannets breeding in the North East Atlantic.
Biological Conservation,
156, 43-52.
Abstract:
A novel projection technique to identify important at-sea areas for seabird conservation: an example using Northern gannets breeding in the North East Atlantic
Seabirds are well monitored and protected at their breeding grounds but spend most of their life at sea, where they are less well monitored and afforded little protection. In an attempt to address this dichotomy, attention has been directed toward establishing a network of marine reserves for seabirds, based largely on information from at-sea surveys and/or biotelemetry studies. Nevertheless, these approaches are costly, are typically only available for a limited number of locations, and not suitable for species that have either poor at-sea detectability or are unable to carry tracking devices. Here we develop a technique to identify important areas for breeding seabirds based on at-sea projections from colonies. Synthesising data from colony surveys with detailed information on population dynamics, foraging ecology and near-colony behaviour, we project colony-specific foraging distributions of the Northern gannet (. Morus bassanus) at colonies in the UK, Ireland and France. We test the ability of our models to identify at-sea hotspots through comparison with existing data from biotelemetry studies and at-sea visual surveys. These models show a positive spatial correlation with one of the most intensive at-sea seabird survey datasets. While there are limitations to estimating at-sea distributions of seabirds, implemented appropriately, we propose they could prove useful in identifying potential Marine Protected Areas for seabirds. Moreover, these models could be developed to suit a range of species or whole communities and provide a theoretical framework for the study of factors such as colony size regulation. © 2012 Elsevier Ltd.
Abstract.
Marco A, Abella E, Liria-Loza A, Martins S, López O, Jiménez-Bordón S, Medina M, Oujo C, Gaona P, Godley BJ, et al (2012). Abundance and exploitation of loggerhead turtles nesting in Boa Vista island, Cape Verde: the only substantial rookery in the eastern Atlantic.
Animal Conservation,
15(4), 351-360.
Abstract:
Abundance and exploitation of loggerhead turtles nesting in Boa Vista island, Cape Verde: the only substantial rookery in the eastern Atlantic
The main nesting area for loggerhead turtles in the eastern Atlantic is in the Cape Verde Islands, largely restricted to the island of Boa Vista. Extensive monitoring demonstrated a globally significant population for the species despite a sustained high level of anthropogenic take of nesting females for local consumption. Through an extensive stratified monitoring program across the island in the seasons 2007-2009, we estimated a total of 13955, 12028 and 19950 clutches in the 3 years, respectively. These values indicate that the mean number of nesting females averaged 3700. Considering that a female breed, on average, every 2.4 years, we estimate that the overall number of adult females in the population during these three seasons was 8900. These levels are much higher than those suggested in previous studies which were more constrained in spatial coverage. Our findings indicate that Cape Verde hosts the third largest nesting aggregation for this species in the world after the south-eastern US and Oman, with some sites having a particularly high density of nests, facilitating targeted monitoring and conservation. Consumption of sea turtle meat is a traditional practice in Cape Verde that continues despite national sea turtle protection laws. We estimated that 36, 18 and 5% of nesting females were harvested in the 3 years of the study, respectively. Increasing beach protection and monitoring, ongoing educational programs and cooperative projects with local communities are urgently needed to further safeguard the only major loggerhead nesting aggregation in the eastern Atlantic. © 2012 the Zoological Society of London.
Abstract.
Marco A, Abella E, Liria-Loza A, Martins S, Lopez O, Jimenez-Bordon S, Medina M, Oujo C, Gaona P, Godley BJ, et al (2012). Abundance and exploitation of loggerhead turtles nesting in Boa Vista island, Cape Verde: the only substantial rookery in the eastern Atlantic.
ANIMAL CONSERVATION,
15(4), 351-360.
Author URL.
Merchant ND, Witt MJ, Blondel P, Godley BJ, Smith GH (2012). Assessing sound exposure from shipping in coastal waters using a single hydrophone and Automatic Identification System (AIS) data.
Marine Pollution Bulletin,
64(7), 1320-1329.
Abstract:
Assessing sound exposure from shipping in coastal waters using a single hydrophone and Automatic Identification System (AIS) data
Underwater noise from shipping is a growing presence throughout the world's oceans, and may be subjecting marine fauna to chronic noise exposure with potentially severe long-term consequences. The coincidence of dense shipping activity and sensitive marine ecosystems in coastal environments is of particular concern, and noise assessment methodologies which describe the high temporal variability of sound exposure in these areas are needed. We present a method of characterising sound exposure from shipping using continuous passive acoustic monitoring combined with Automatic Identification System (AIS) shipping data. The method is applied to data recorded in Falmouth Bay, UK. Absolute and relative levels of intermittent ship noise contributions to the 24-h sound exposure level are determined using an adaptive threshold, and the spatial distribution of potential ship sources is then analysed using AIS data. This technique can be used to prioritise shipping noise mitigation strategies in coastal marine environments. © 2012 Elsevier Ltd.
Abstract.
Merchant ND, Witt MJ, Blondel P, Godley BJ, Smith GH (2012). Assessing sound exposure from shipping in coastal waters using a single hydrophone and Automatic Identification System (AIS) data.
Mar Pollut Bull,
64(7), 1320-1329.
Abstract:
Assessing sound exposure from shipping in coastal waters using a single hydrophone and Automatic Identification System (AIS) data.
Underwater noise from shipping is a growing presence throughout the world's oceans, and may be subjecting marine fauna to chronic noise exposure with potentially severe long-term consequences. The coincidence of dense shipping activity and sensitive marine ecosystems in coastal environments is of particular concern, and noise assessment methodologies which describe the high temporal variability of sound exposure in these areas are needed. We present a method of characterising sound exposure from shipping using continuous passive acoustic monitoring combined with Automatic Identification System (AIS) shipping data. The method is applied to data recorded in Falmouth Bay, UK. Absolute and relative levels of intermittent ship noise contributions to the 24-h sound exposure level are determined using an adaptive threshold, and the spatial distribution of potential ship sources is then analysed using AIS data. This technique can be used to prioritize shipping noise mitigation strategies in coastal marine environments.
Abstract.
Author URL.
Witt MJ, Sheehan EV, Bearhop S, Broderick AC, Conley DC, Cotterell SP, Crow E, Grecian WJ, Halsband C, Hodgson DJ, et al (2012). Assessing wave energy effects on biodiversity: the Wave Hub experience.
Philosophical Transactions of the Royal Society A: Mathematical, Physical and Engineering Sciences,
370(1959), 502-529.
Abstract:
Assessing wave energy effects on biodiversity: the Wave Hub experience
Marine renewable energy installations harnessing energy from wind, wave and tidal resources are likely to become a large part of the future energy mix worldwide. The potential to gather energy from waves has recently seen increasing interest, with pilot developments in several nations. Although technology to harness wave energy lags behind that of wind and tidal generation, it has the potential to contribute significantly to energy production. As wave energy technology matures and becomes more widespread, it is likely to result in further transformation of our coastal seas. Such changes are accompanied by uncertainty regarding their impacts on biodiversity. To date, impacts have not been assessed, as wave energy converters have yet to be fully developed. Therefore, there is a pressing need to build a framework of understanding regarding the potential impacts of these technologies, underpinned by methodologies that are transferable and scalable across sites to facilitate formal meta-analysis. We first review the potential positive and negative effects of wave energy generation, and then, with specific reference to our work at the Wave Hub (a wave energy test site in southwest England, UK), we set out the methodological approaches needed to assess possible effects of wave energy on biodiversity. We highlight the need for national and international research clusters to accelerate the implementation of wave energy, within a coherent understanding of potential effects-both positive and negative. © 2011 the Royal Society.
Abstract.
Witt MJ, Sheehan EV, Bearhop S, Broderick AC, Conley DC, Cotterell SP, Crow E, Grecian WJ, Halsband C, Hodgson DJ, et al (2012). Assessing wave energy effects on biodiversity: the Wave Hub experience. Philosophical Transactions of the Royal Society A: Mathematical, Physical and Engineering Sciences, 370(1959), 502-529.
Witt MJ, Hardy T, Johnson L, McClellan CM, Pikesley SK, Ranger S, Richardson PB, Solandt JL, Speedie C, Williams R, et al (2012). Basking sharks in the northeast Atlantic: Spatio-temporal trends from sightings in UK waters.
Marine Ecology Progress Series,
459, 121-134.
Abstract:
Basking sharks in the northeast Atlantic: Spatio-temporal trends from sightings in UK waters
Basking sharks Cetorhinus maximus have undergone widespread historic exploitation in the northeast Atlantic and are of conservation concern. A greater knowledge of their spatial and temporal habitat use is required to better inform subsequent monitoring and management strategies. Techniques such as light-based geolocation have provided great insights into individual movements, but currently available data do not permit extrapolation to the population level. Public recording schemes may, however, help to fill shortfalls in data gathering, especially when analysed in conjunction with data from these other techniques. We analysed 11 781 records (from 1988 to 2008) from 2 public recording databases operating in the UK. We describe 3 sightings hotspots: western Scotland, Isle of Man and southwest England, and highlight the marked seasonality of basking shark sightings, which were at their greatest during the northeast Atlantic summer (June to August). We further highlight a significant correlation between the duration of the sightings season in each year and the North Atlantic Oscillation, an atmosphere-ocean climate oscillation that has been linked to forcing of marine ecosystems. We augment patterns from public sightings records with effort-related data collected by boat-based transects at 2 regional sightings hotspots (western Scotland and southwest England). Analysis of reported body size data indicated that the annual proportion of small sharks (6 m) remained constant. These patterns may be indicative of a population recovery following systematic harvesting in the 20th century. © Inter-Research 2012.
Abstract.
Pikesley SK, Witt MJ, Hardy T, Loveridge J, Loveridge J, Williams R, Godley BJ (2012). Cetacean sightings and strandings: Evidence for spatial and temporal trends?.
Journal of the Marine Biological Association of the United Kingdom,
92(8), 1809-1820.
Abstract:
Cetacean sightings and strandings: Evidence for spatial and temporal trends?
Cetacean species and their habitats are under threat and effective marine management mitigation strategies require knowledge and understanding of cetacean ecology. This requires data that are challenging and expensive to obtain; incidental sightings/strandings data are potential underused resources. In this study, incidental cetacean sightings (N = 6631) and strandings (N = 1856) in coastal waters of Cornwall, south-west Britain (1991 to 2008) were analysed for evidence of spatial and temporal patterns or trends. Eighteen species were recorded sighted and/or stranded; key species were identified as bottlenose dolphin (Tursiops truncatus), harbour porpoise (Phocoena phocoena), common dolphin (Delphinus delphis), Risso's dolphin (Grampus griseus) and minke whale (Balaenoptera acutorostrata). There were significant decreases in bottlenose dolphin sightings and pod size but an increase in harbour porpoise and minke whale sightings. Cetacean strandings showed a recent decrease over time although there was a significant positive trend in harbour porpoise strandings that correlated with sightings. Incidence of sightings and strandings were both greater on the south coast than the north coast. When Marine Tour Operator data were analysed, distinct species-specific inshore and offshore habitat use was evident. With rigorous interrogation and editing, significant patterns and trends were gained from incidentally collected data, highlighting the importance of public engagement with such recording schemes and the potential of these underused resources. © 2012 Marine Biological Association of the United Kingdom.
Abstract.
Rees AF, Al-Kiyumi A, Broderick AC, Papathanasopoulou N, Godley BJ (2012). Conservation related insights into the behaviour of the olive ridley sea turtle Lepidochelys olivacea nesting in Oman.
Marine Ecology Progress Series,
450, 195-205.
Abstract:
Conservation related insights into the behaviour of the olive ridley sea turtle Lepidochelys olivacea nesting in Oman
We followed the movements of 9 adult female olive ridley turtles Lepidochelys olivacea after nesting on Masirah Island, Oman, using satellite tracking. Their post-breeding migrations ranged from 85 to 796 km. Three individuals travelled north to foraging grounds in Pakistan, Iran and the United Arab Emirates. The other 6 turtles remained in Omani seas for extended periods (mean ± SD = 171.3 ± 109.4 d; range = 40 to 310 d). These locally resident turtles experienced biannual cooling of sea temperatures due to the effect of the west Arabian Sea upwelling which was not experienced by those that migrated to the north. Indications of disparity in turtle size between foraging locations are identified for the first time in this species. The majority of turtles (8) settled in coastal areas of water depth
Abstract.
Rees AF, Al-Kiyumi A, Broderick AC, Papathanasopoulou N, Godley BJ (2012). Each to their own: Inter-specific differences in migrations of Masirah Island turtles.
Chelonian Conservation and Biology,
11(2), 243-248.
Abstract:
Each to their own: Inter-specific differences in migrations of Masirah Island turtles
We tracked two adult female green turtles (Chelonia mydas) from their nesting location on Masirah Island, Oman (lat 20.441°N, long 58.843°E) into the Red Sea. Comparing these tracks with published movements of nesting loggerhead (Caretta caretta) and olive ridley (Lepidochelys olivacea) turtles, also tracked from Masirah, revealed remarkably different inter-specific patterns of post-nesting dispersal. High-capacity artisanal fisheries, with undescribed levels of sea turtle bycatch, exist within the region, making introduction of effective conservation measures difficult. © 2012 Chelonian Research Foundation.
Abstract.
Rees AF, Margaritoulis D, Newman R, Riggall TE, Tsaros P, Zbinden JA, Godley BJ (2012). Ecology of loggerhead marine turtles Caretta caretta in a neritic foraging habitat: movements, sex ratios and growth rates. Marine Biology, 1-11.
Pikesley SK, Witt MJ, Hardy T, Loveridge J, Loveridge J, Williams R, Godley BJ (2012). Erratum: Cetacean sightings and strandings: Evidence for spatial and temporal trends? (Journal of the Marine Biological Association of the United Kingdom DOI: 10.1017/S0025315411000464). Journal of the Marine Biological Association of the United Kingdom, 92(8), 1821-1822.
Scott R, Hodgson DJ, Witt MJ, Coyne MS, Adnyana W, Blumenthal JM, Broderick AC, Canbolat AF, Catry P, Ciccione S, et al (2012). Global analysis of satellite tracking data shows that adult green turtles are significantly aggregated in Marine Protected Areas.
Global Ecology and Biogeography,
21(11), 1053-1061.
Abstract:
Global analysis of satellite tracking data shows that adult green turtles are significantly aggregated in Marine Protected Areas
Aim Tracking technologies are often proposed as a method to elucidate the complex migratory life histories of migratory marine vertebrates, allowing spatially explicit threats to be identified and mitigated. We conducted a global analysis of foraging areas of adult green turtles (Chelonia mydas) subject to satellite tracking (n= 145) and the conservation designation of these areas according to International Union for Conservation of Nature criteria. Location the green turtle has a largely circumtropical distribution, with adults migrating up to thousands of kilometres between nesting beaches and foraging areas, typically in neritic seagrass or algal beds. Methods We undertook an assessment of satellite tracking projects that followed the movements of green turtles in tropical and subtropical habitats. This approach was facilitated by the use of the Satellite Tracking and Analysis Tool (http://www.seaturtle.org) and the integration of publicly available data on Marine Protected Areas (MPAs). Results We show that turtles aggregate in designated MPAs far more than would be expected by chance when considered globally (35% of all turtles were located within MPAs) or separately by ocean basin (Atlantic 67%, Indian 34%, Mediterranean 19%, Pacific 16%). Furthermore, we show that the size, level of protection and time of establishment of MPAs affects the likelihood of MPAs containing foraging turtles, highlighting the importance of large, well-established reserves. Main conclusions Our findings constitute compelling evidence of the world-wide effectiveness of extant MPAs in circumscribing important foraging habitats for a marine megavertebrate. © 2012 Blackwell Publishing Ltd.
Abstract.
Scott R, Hodgson DJ, Witt MJ, Coyne MS, Blumenthal JM, Broderick AC, Richardson PB, Rees AF, Godley BJ, Coyne MS, et al (2012). Global analysis of satellite tracking data shows that adult green turtles are significantly aggregated in Marine Protected Areas.
Global Ecology and BiogeographyAbstract:
Global analysis of satellite tracking data shows that adult green turtles are significantly aggregated in Marine Protected Areas
Aim Tracking technologies are often proposed as a method to elucidate the complex migratory life histories of migratory marine vertebrates, allowing spatially explicit threats to be identified and mitigated. We conducted a global analysis of foraging areas of adult green turtles (Chelonia mydas) subject to satellite tracking (n= 145) and the conservation designation of these areas according to International Union for Conservation of Nature criteria. Location the green turtle has a largely circumtropical distribution, with adults migrating up to thousands of kilometres between nesting beaches and foraging areas, typically in neritic seagrass or algal beds. Methods We undertook an assessment of satellite tracking projects that followed the movements of green turtles in tropical and subtropical habitats. This approach was facilitated by the use of the Satellite Tracking and Analysis Tool () and the integration of publicly available data on Marine Protected Areas (MPAs). Results We show that turtles aggregate in designated MPAs far more than would be expected by chance when considered globally (35% of all turtles were located within MPAs) or separately by ocean basin (Atlantic 67%, Indian 34%, Mediterranean 19%, Pacific 16%). Furthermore, we show that the size, level of protection and time of establishment of MPAs affects the likelihood of MPAs containing foraging turtles, highlighting the importance of large, well-established reserves. Main conclusions Our findings constitute compelling evidence of the world-wide effectiveness of extant MPAs in circumscribing important foraging habitats for a marine megavertebrate. © 2012 Blackwell Publishing Ltd.
Abstract.
Richardson PB, Broderick AC, Coyne MS, Gore S, Gumbs JC, Pickering A, Ranger S, Witt MJ, Godley BJ (2012). Leatherback turtle conservation in the Caribbean UK overseas territories: Act local, think global?. Marine Policy
Merchant ND, Witt MJ, Blondel P, Godley BJ, Smith GH (2012). Long-term monitoring of sound exposure from shipping in coastal waters. 11th European Conference on Underwater Acoustics 2012, ECUA 2012, 34 2(PART 3), 1026-1033.
Casale P, Broderick AC, Freggi D, Mencacci R, Fuller WJ, Godley BJ, Luschi P (2012). Long-term residence of juvenile loggerhead turtles to foraging grounds: a potential conservation hotspot in the Mediterranean.
Aquatic Conservation: Marine and Freshwater Ecosystems,
22(2), 144-154.
Abstract:
Long-term residence of juvenile loggerhead turtles to foraging grounds: a potential conservation hotspot in the Mediterranean
Identifying highly frequented areas is a priority for sea turtle conservation. Although juveniles represent the bulk of the population, a minority of studies have investigated their movement patterns. Six large juvenile loggerhead turtles that were found and released in an important foraging ground in the Mediterranean, the Tunisian continental shelf were tracked. Tracking data were obtained via satellite for periods ranging from 120 to 225days and allowed the identification of high use areas. All turtles generally performed apparently non-directed, wandering movements in waters with a wide range of seafloor depths. They showed clear residential behaviour to the region with no evident seasonal pattern. Core areas of residence were in the neritic zone or on the edge of the continental shelf, largely overlapping among individuals, and were much smaller than residential oceanic areas reported elsewhere. When integrated into current knowledge, these results suggest an ecological-behavioural model of a gradual shift from a pelagic-vagile to a benthic-sedentary life style with progressive reduction of home ranges. They also highlight an area of the continental shelf and offshore waters as potential core foraging ground for large juvenile loggerhead turtles in the Mediterranean informing future spatial management for loggerhead turtles. © 2012 John Wiley & Sons, Ltd.
Abstract.
Casale P, Broderick AC, Freggi D, Mencacci R, Fuller WJ, Godley BJ, Luschi P (2012). Long-term residence of juvenile loggerhead turtles to foraging grounds: a potential conservation hotspot in the Mediterranean. Aquatic Conservation: Marine and Freshwater Ecosystems
Leeney RH, Witt MJ, Broderick AC, Buchanan J, Jarvis DS, Richardson PB, Godley BJ (2012). Marine megavertebrates of Cornwall and the Isles of Scilly: Relative abundance and distribution.
Journal of the Marine Biological Association of the United Kingdom,
92(8), 1823-1833.
Abstract:
Marine megavertebrates of Cornwall and the Isles of Scilly: Relative abundance and distribution
We document patterns of distribution and relative abundance of marine megavertebrate fauna around Cornwall and the Isles of Scilly from a combination of aerial and boat-based surveying. Between January 2006 and November 2007, 20 aerial surveys were undertaken, comprising over 40 hours of on-effort flying time. In April to October of these years, 27 effort-corrected ferry surveys were also conducted from a passenger ferry travelling between Cornwall and the Isles of Scilly. Opportunistic sightings were also logged by the crew members of the ferry and another vessel travelling regularly along the same route on 155 days. Ten megavertebrate species were sighted: basking sharks Cetorhinus maximus, sunfish Mola mola, common dolphins Delphinus delphis, harbour porpoise Phocoena phocoena, grey seals Halichoerus grypus, Risso's dolphins Grampus griseus, bottlenose dolphins Tursiops truncatus, minke whales Balaenoptera acutorostrata, long-finned pilot whales Globicephala melas and killer whale Orcinus orca. During aerial surveys, 206 sighting events of seven species were made, compared with 145 sighting events of eight species during ferry surveys and 293 sighting events of 10 species from opportunistic ship-board data collection efforts. Seasonal and spatial patterns in species occurrence were evident. Basking sharks were the most commonly-sighted species in the region and were relatively abundant throughout the estimated 5 km-wide strip of coastal waters covered by the aerial surveys, during spring and summer. Ferry surveys and opportunistic vessel-based sightings data confirmed that the distribution of surface-feeding aggregations of this species was largely around the coasts. Despite the limited scope of this study, it has provided valuable baseline data, and possible insights into the marine biodiversity of the region. © 2012 Marine Biological Association of the United Kingdom.
Abstract.
Hawkes LA, Tomás J, Revuelta O, León YM, Blumenthal JM, Broderick AC, Fish M, Raga JA, Witt MJ, Godley BJ, et al (2012). Migratory patterns in hawksbill turtles described by satellite tracking.
Marine Ecology Progress Series,
461, 223-232.
Abstract:
Migratory patterns in hawksbill turtles described by satellite tracking
The advent of telemetry has improved knowledge of the spatio-temporal distribution of marine species of conservation concern. Among the sea turtles, the movements of the hawksbill turtle Eretmochelys imbricata are among the least well described. We tracked 10 adult female hawksbill turtles by satellite after nesting in the Dominican Republic (DR) and describe a dichotomy in patterns of movement: some (n = 2) turtles remained in the DR, while others migrated to waters off Honduras and Nicaragua (n = 5) and the Bahamas (n = 1). Transmitters on 2 turtles failed during migration, before they reached their final foraging grounds. We present results from long tracking durations for 3 turtles, including 3 entire remigration intervals, high-lighting foraging ground and nest-site fidelity. Threats to hawksbill turtles are not well documented for Nicaragua or neighbouring Honduras and represent a major information gap. We suggest that directing conservation efforts to regionally important foraging areas, such as those in Nicaragua, and strengthening national conservation in each nation with significant hawksbill nesting offers a clear way forward for the conservation of hawksbill turtles in the region. © Inter-Research 2012 · www.int-res.com.
Abstract.
Hazen EL, Maxwell SM, Bailey H, Bograd SJ, Hamann M, Gaspar P, Godley BJ, Shillinger GL (2012). Ontogeny in marine tagging and tracking science: Technologies and data gaps.
Marine Ecology Progress Series,
457, 221-240.
Abstract:
Ontogeny in marine tagging and tracking science: Technologies and data gaps
The field of marine tagging and tracking has grown rapidly in recent years as tag sizes have decreased and the diversity of sensors has increased. Tag data provide a unique view on individual movement patterns, at different scales than shipboard surveys, and have been used to discover new habitat areas, characterize oceanographic features, and delineate stock structures, among other purposes. Due to the necessity for small tag-to-body size ratio, tags have largely been deployed on adult animals, resulting in a relative paucity of data on earlier life history stages. In this study, we reviewed tagging efforts on multiple life history stages for seabirds, marine mammals, marine turtles, and fish and enumerated studies focusing on each guild that targeted larvae, juveniles or hatchlings. We found that turtles and fish had higher proportion of studies focusing on juveniles (>20%) than seabirds and marine mammals (
Abstract.
Moncada FG, Hawkes LA, Fish MR, Godley BJ, Manolis SC, Medina Y, Nodarse G, Webb GJW (2012). Patterns of dispersal of hawksbill turtles from the Cuban shelf inform scale of conservation and management.
Biological Conservation,
148(1), 191-199.
Abstract:
Patterns of dispersal of hawksbill turtles from the Cuban shelf inform scale of conservation and management
Conserving and managing populations of marine vertebrates can be complex when they occupy the waters of multiple nations, crossing heterogeneous legal and management landscapes. Hawksbill turtles (. Eretmochelys imbricata) are subject to varying levels of use in Caribbean countries and their conservation and management is complicated by the extent to which they are a 'shared' resource. In 1997 and 2000, Cuba attempted to 'downlist' hawksbills from Cuban waters to CITES Appendix II to allow limited international trade. The research on movement and dispersal of hawksbills reported here was undertaken to better inform discussion about the impacts of their harvest. Flipper tagging and satellite tracking demonstrate that the majority of study turtles remained in Cuban territorial waters. of 1170 hawksbills tagged (525 adults and 606 juveniles), 12% (. n=. 143) were recaptured. All recaptured adults (. n=. 16 males, 38 nesting females and 30 adult females in-water) were in Cuban waters. of the 59 juveniles recaptured, only four recaptures were outside Cuban waters (Nicaragua. =. 2, Colombia. =. 1, USA. =. 1). Fourteen hawksbills tagged in the waters of other nations were recaptured in Cuban waters. We also satellite tracked 21 turtles (one adult male, ten nesting females and ten non-nesting adult females), of which five tags failed, 11 stayed in Cuban waters for the duration of transmissions (1-809. days) and five foraged in the waters of other nations (Mexico. n=. 1 an adult female; Honduras. n=. 2, both post-nesting turtles; Colombia. n=. 1 an adult female; and the eastern Lesser Antilles. n=. 1, an adult male), with differences for nesting and non-nesting turtles. Our results, demonstrating extended site fidelity within Cuban waters, suggest that strengthening national management within national jurisdictions that host hawksbill turtles is fundamental to improving regional conservation as a whole. © 2012 Elsevier Ltd.
Abstract.
Revuelta O, León YM, Feliz P, Godley BJ, Raga JA, Tomás J (2012). Protected areas host important remnants of marine turtle nesting stocks in the Dominican Republic.
ORYX,
46(3), 348-358.
Abstract:
Protected areas host important remnants of marine turtle nesting stocks in the Dominican Republic
Nesting by marine turtles in the Caribbean has declined considerably, mainly because of human exploitation, but there has previously been no monitoring in the Dominican Republic. We present the first detailed assessment of the status of marine turtle nesting in the country, based on surveys during 2006-2010. Nesting populations of hawksbill Eretmochelys imbricata and leatherback turtle Dermochelys coriacea are of regional importance and the green turtle Chelonia mydas is still present, although nesting in low numbers. The two main nesting sites are within protected areas: the Jaragua National Park in the south-west, important for leatherback turtles (mean of 126 nests per season), and Del Este National Park on Saona Island in the south-east, principally for hawksbill turtles (mean of 100 nests per season). Comparison with historical data suggests all rookeries are profoundly reduced in size. Although the main nesting beaches are within protected areas, illegal egg-take and meat consumption continues there, and also elsewhere in the country. © 2012 Fauna & Flora International.
Abstract.
Wright LI, Fuller WJ, Godley BJ, McGowan A, Tregenza T, Broderick AC (2012). Reconstruction of paternal genotypes over multiple breeding seasons reveals male green turtles do not breed annually.
Molecular Ecology,
21(14), 3625-3635.
Abstract:
Reconstruction of paternal genotypes over multiple breeding seasons reveals male green turtles do not breed annually
For species of conservation concern, knowledge of key life-history and demographic components, such as the number and sex ratio of breeding adults, is essential for accurate assessments of population viability. Species with temperature-dependent sex determination can produce heavily biased primary sex ratios, and there is concern that adult sex ratios may be similarly skewed or will become so as a result of climate warming. Prediction and mitigation of such impacts are difficult when life-history information is lacking. In marine turtles, owing to the difficultly in observing males at sea, the breeding interval of males is unknown. It has been suggested that male breeding periodicity may be shorter than that of females, which could help to compensate for generally female-biased sex ratios. Here we outline how the use of molecular-based paternity analysis has allowed us, for the first time, to assess the breeding interval of male marine turtles across multiple breeding seasons. In our study rookery of green turtles (Chelonia mydas), 97% of males were assigned offspring in only one breeding season within the 3-year study period, strongly suggesting that male breeding intervals are frequently longer than 1 year at this site. Our results also reveal a sex ratio of breeding adults of at least 1.3 males to each female. This study illustrates the utility of molecular-based parentage inference using reconstruction of parental genotypes as a method for monitoring the number and sex ratio of breeders in species where direct observations or capture are difficult. © 2012 Blackwell Publishing Ltd.
Abstract.
Wright LI, Fuller WJ, Godley BJ, McGowan A, Tregenza T, Broderick AC (2012). Reconstruction of paternal genotypes over multiple breeding seasons reveals male green turtles do not breed annually.
Mol Ecol,
21(14), 3625-3635.
Abstract:
Reconstruction of paternal genotypes over multiple breeding seasons reveals male green turtles do not breed annually.
For species of conservation concern, knowledge of key life-history and demographic components, such as the number and sex ratio of breeding adults, is essential for accurate assessments of population viability. Species with temperature-dependent sex determination can produce heavily biased primary sex ratios, and there is concern that adult sex ratios may be similarly skewed or will become so as a result of climate warming. Prediction and mitigation of such impacts are difficult when life-history information is lacking. In marine turtles, owing to the difficultly in observing males at sea, the breeding interval of males is unknown. It has been suggested that male breeding periodicity may be shorter than that of females, which could help to compensate for generally female-biased sex ratios. Here we outline how the use of molecular-based paternity analysis has allowed us, for the first time, to assess the breeding interval of male marine turtles across multiple breeding seasons. In our study rookery of green turtles (Chelonia mydas), 97% of males were assigned offspring in only one breeding season within the 3-year study period, strongly suggesting that male breeding intervals are frequently longer than 1year at this site. Our results also reveal a sex ratio of breeding adults of at least 1.3 males to each female. This study illustrates the utility of molecular-based parentage inference using reconstruction of parental genotypes as a method for monitoring the number and sex ratio of breeders in species where direct observations or capture are difficult.
Abstract.
Author URL.
Lewison R, Oro D, Godley BJ, Underhill L, Bearhop S, Wilson RP, Ainley D, Arcos JM, Boersma PD, Borboroglu PG, et al (2012). Research priorities for seabirds: Improving conservation and management in the 21st century.
Endangered Species Research,
17(2), 93-121.
Abstract:
Research priorities for seabirds: Improving conservation and management in the 21st century
Seabirds are facing a growing number of threats in both terrestrial and marine habitats, and many populations have experienced dramatic changes over past decades. Years of seabird research have improved our understanding of seabird populations and provided a broader understanding of marine ecological processes. In an effort to encourage future research and guide seabird conservation science, seabird researchers from 9 nations identified the 20 highest priority research questions and organized these into 6 general categories: (1) population dynamics, (2) spatial ecology, (3) tropho-dynamics, (4) fisheries interactions, (5) response to global change, and (6) management of anthropogenic impacts (focusing on invasive species, contaminants and protected areas). For each category, we provide an assessment of the current approaches, challenges and future directions. While this is not an exhaustive list of all research needed to address the myriad conservation challenges seabirds face, the results of this effort represent an important synthesis of current expert opinion across sub-disciplines within seabird ecology. As this synthesis highlights, research, in conjunction with direct management, education, and community engagement, can play an important role in facilitating the conservation and management of seabird populations and of the ocean ecosystems on which they and we depend. © Inter-Research 2012.
Abstract.
Graham RT, Witt MJ, Castellanos DW, Remolina F, Maxwell S, Godley BJ, Hawkes LA (2012). Satellite tracking of manta rays highlights challenges to their conservation.
PLoS One,
7(5).
Abstract:
Satellite tracking of manta rays highlights challenges to their conservation.
We describe the real-time movements of the last of the marine mega-vertebrate taxa to be satellite tracked - the giant manta ray (or devil fish, Manta birostris), the world's largest ray at over 6 m disc width. Almost nothing is known about manta ray movements and their environmental preferences, making them one of the least understood of the marine mega-vertebrates. Red listed by the International Union for the Conservation of Nature as 'Vulnerable' to extinction, manta rays are known to be subject to direct and incidental capture and some populations are declining. Satellite-tracked manta rays associated with seasonal upwelling events and thermal fronts off the Yucatan peninsula, Mexico, and made short-range shuttling movements, foraging along and between them. The majority of locations were received from waters shallower than 50 m deep, representing thermally dynamic and productive waters. Manta rays remained in the Mexican Exclusive Economic Zone for the duration of tracking but only 12% of tracking locations were received from within Marine Protected Areas (MPAs). Our results on the spatio-temporal distribution of these enigmatic rays highlight opportunities and challenges to management efforts.
Abstract.
Author URL.
Garnier J, Hill N, Guissamulo A, Silva I, Witt M, Godley B (2012). Status and community-based conservation of marine turtles in the northern Querimbas Islands (Mozambique).
ORYX,
46(3), 359-367.
Abstract:
Status and community-based conservation of marine turtles in the northern Querimbas Islands (Mozambique)
Situated in the northernmost part of Mozambique, the northern Querimbas Islands support some of the most diverse and pristine coral reefs in the Western Indian Ocean. The community-based turtle conservation programme that we developed on Vamizi Island has facilitated the identification and protection of a key nesting site for the green marine turtle Chelonia mydas in Mozambique, with a mean of 122 nests per year. The area is also used by nesting female and immature hawksbill turtles Eretmochelys imbricata. Nesting activity of green turtles was observed all year round, with a peak in the summer (February-March). Incubation periods of this species showed seasonal fluctuations inversely correlated with air temperature. Hatching success was high (87%) when nests were not lost through tidal overwash and erosion, which affected nearly 40% of all nests in 2007. Using satellite tracking of four green turtles nesting on Vamizi we identified foraging grounds in marine protected areas in Kenya, Tanzania and north-west Madagascar. Migratory routes of two individuals along the East African coast were generally neritic and all passed through the waters of multiple nations and as many as six marine conservation areas, emphasizing the importance of regional cooperation. Awareness programmes were also conducted with resource users, and the development of a community-based management system triggered the creation of a marine sanctuary by the local community. © 2012 Fauna & Flora International.
Abstract.
Shillinger GL, Bailey H, Bograd SJ, Hazen EL, Hamann M, Gaspar P, Godley BJ, Wilson RP, Spotila JR (2012). Tagging through the stages: Technical and ecological challenges in observing life histories through biologging.
Marine Ecology Progress Series,
457, 165-170.
Abstract:
Tagging through the stages: Technical and ecological challenges in observing life histories through biologging
Biologging data have provided important insights into the biology of marine mammals, sea turtles, birds, fish, and some invertebrates. These techniques have primarily targeted adult organisms. As a result, the early life histories of many marine species are still poorly understood. Technological advances have enabled attachment of smaller tags to young animals, although equipment limitations, access to and capture/handling of animals, and equipment and data recovery pose additional challenges to researchers. In this Theme Section, we highlight novel uses of biologging data on juvenile animals, including reviews of tagging efforts on multiple lifehistory stages and the integration of oceanographic data in tagging efforts. © Inter-Research 2012.
Abstract.
Alfaro-Shigueto J, Mangel JC, Dutton PH, Seminoff JA, Godley BJ (2012). Trading information for conservation: a novel use of radio broadcasting to reduce sea turtle bycatch.
ORYX,
46(3), 332-339.
Author URL.
Wright LI, Stokes KL, Fuller WJ, Godley BJ, McGowan A, Snape R, Tregenza T, Broderick AC (2012). Turtle mating patterns buffer against disruptive effects of climate change.
Proc Biol Sci,
279(1736), 2122-2127.
Abstract:
Turtle mating patterns buffer against disruptive effects of climate change.
For organisms with temperature-dependent sex determination (TSD), skewed offspring sex ratios are common. However, climate warming poses the unique threat of producing extreme sex ratio biases that could ultimately lead to population extinctions. In marine turtles, highly female-skewed hatchling sex ratios already occur and predicted increases in global temperatures are expected to exacerbate this trend, unless species can adapt. However, it is not known whether offspring sex ratios persist into adulthood, or whether variation in male mating success intensifies the impact of a shortage of males on effective population size. Here, we use parentage analysis to show that in a rookery of the endangered green turtle (Chelonia mydas), despite an offspring sex ratio of 95 per cent females, there were at least 1.4 reproductive males to every breeding female. Our results suggest that male reproductive intervals may be shorter than the 2-4 years typical for females, and/or that males move between aggregations of receptive females, an inference supported by our satellite tracking, which shows that male turtles may visit multiple rookeries. We suggest that male mating patterns have the potential to buffer the disruptive effects of climate change on marine turtle populations, many of which are already seriously threatened.
Abstract.
Author URL.
Stipala J, Lutzmánn N, Malonza PK, Borghesio L, Wilkinson P, Godley B, Evans MR (2011). A new species of chameleon (Sauria: Chamaeleonidae) from the highlands of northwest Kenya.
Zootaxa(3002), 1-16.
Abstract:
A new species of chameleon (Sauria: Chamaeleonidae) from the highlands of northwest Kenya
A new species of chameleon, Trioceros nyirit sp. nov. is described from the northwest highlands of Kenya. It is morphologically similar to T. hoehnelii and T. narraioca, possessing a short rostral appendage, but differs from them by having a straight or weakly curved parietal crest and forward-pointing rostral projection. A phylogeny based on mitochondrial DNA shows that the proposed new taxon is a distinct clade within the bitaeniatus-group and a sister lineage to T. schubotzi. Its distribution appears to be restricted to the Cherangani Hills and adjacent Mtelo massif to the north. It is associated with afromontane forest edge, afroalpine ericaceous vegetation and also occurs in agricultural landscapes. © 2011 Magnolia Press.
Abstract.
Merchant ND, Witt MJ, Blondel P, Godley BJ, Smith GH (2011). Ambient noise in the western English channel: Temporal variability due to shipping and biological sources. Proceedings of the Institute of Acoustics, 33(PART 5), 27-29.
Pikesley SK, Witt MJ, Hardy T, Loveridge J, Loveridge J, Williams R, Godley BJ (2011). Cetacean sightings and strandings: evidence for spatial and temporal trends?. Journal of the Marine Biological Association of the United Kingdom, FirstView, 1-12-1-12.
Weber SB, Broderick AC, Groothuis TGG, Ellick J, Godley BJ, Blount JD (2011). Fine-scale thermal adaptation in a green turtle nesting population.
Proceedings of the Royal Society of London B: Biological SciencesAbstract:
Fine-scale thermal adaptation in a green turtle nesting population
The effect of climate warming on the reproductive success of ectothermic animals is currently a subject of major conservation concern. However, for many threatened species we still know surprisingly little about the extent of naturally-occurring adaptive variation in heat tolerance. Here, we show that the thermal tolerances of green turtle (Chelonia mydas) embryos in a single, island-breeding population have diverged in response to the contrasting incubation temperatures of nesting beaches just a few kilometres apart. In natural nests and in a common-garden rearing experiment, the offspring of females nesting on a naturally hot (black sand) beach survived better and grew larger at hot incubation temperatures compared to the offspring of females nesting on a cooler (pale sand) beach nearby. These differences were due to shallower thermal reaction norms in the hot beach population, rather than a shift in thermal optima, and were not related to maternal provisioning of resources into eggs. Our results suggest that marine turtle nesting behaviour can drive adaptive differentiation at surprisingly fine spatial scales, and have important implications for how we define conservation units for protection. In particular, previous studies may have underestimated the extent of adaptive structuring in marine turtle populations which may significantly affect their capacity to respond to environmental change.
Abstract.
Hawkes LA, Witt MJ, Broderick AC, Coker JW, Coyne MS, Dodd M, Frick MG, Godfrey MH, Griffin DB, Murphy SR, et al (2011). Home on the range: Spatial ecology of loggerhead turtles in Atlantic waters of the USA.
Diversity and Distributions,
17(4), 624-640.
Abstract:
Home on the range: Spatial ecology of loggerhead turtles in Atlantic waters of the USA
Aim Although satellite tracking has yielded much information regarding the migrations and habitat use of threatened marine species, relatively little has been published about the environmental niche for loggerhead sea turtles Caretta caretta in north-west Atlantic waters. Location North Carolina, South Carolina and Georgia, USA. Methods We tracked 68 adult female turtles between 1998 and 2008, one of the largest sample sizes to date, for 372.2±210.4days (mean±SD). Results We identified two strategies: (1) 'seasonal' migrations between summer and winter coastal areas (n=47), although some turtles made oceanic excursions (n=4) and (2) occupation of more southerly 'year-round' ranges (n=18). Seasonal turtles occupied summer home ranges of 645.1km2 (median, n = 42; using α-hulls) predominantly north of 35° latitude and winter home ranges of 339.0km2 (n=24) in a relatively small area on the narrow shelf off North Carolina. We tracked some of these turtles through successive summer (n=8) and winter (n=3) seasons, showing inter-annual home range repeatability to within 14.5km of summer areas and 10.3km of winter areas. For year-round turtles, home ranges were 1889.9km2. Turtles should be tracked for at least 80days to reliably estimate the home range size in seasonal habitats. The equivalent minimum duration for 'year-round' turtles is more complex to derive. We define an environmental envelope of the distribution of North American loggerhead turtles: warm waters (between 18.2 and 29.2°C) on the coastal shelf (in depths of 3.0-89.0m). Main conclusions Our findings show that adult female loggerhead turtles show predictable, repeatable home range behaviour and do not generally leave waters of the USA, nor the continental shelf (
Abstract.
Scales KL, Lewis JA, Lewis JP, Castellanos D, Godley BJ, Graham RT (2011). Insights into habitat utilisation of the hawksbill turtle, Eretmochelys imbricata (Linnaeus, 1766), using acoustic telemetry.
Journal of Experimental Marine Biology and Ecology,
407(1), 122-129.
Abstract:
Insights into habitat utilisation of the hawksbill turtle, Eretmochelys imbricata (Linnaeus, 1766), using acoustic telemetry
Patterns of distribution, key biometric parameters and home range extent were determined for hawksbill turtles at Lighthouse Reef Atoll (LRA), Belize over two field seasons (16days, 2009; 30days, 2010). Relative abundance was determined using 49 sightings transects (≈1km) distributed across the atoll and of all turtles encountered (n=68), 91% were immature (CCLmin≤65cm). Habitat type was significantly correlated with abundance, with more turtles encountered on the coral reef than in the lagoon (GzLMM, Χ22=6.85, p
Abstract.
Mangel JC, Whitty T, Medina-Vogel G, Alfaro-Shigueto J, Cáceres C, Godley BJ (2011). Latitudinal variation in diet and patterns of human interaction in the marine otter.
Marine Mammal Science,
27(2).
Abstract:
Latitudinal variation in diet and patterns of human interaction in the marine otter
The marine otter (Lontra felina) inhabits patches of rocky coastline from central Peru to southern Chile and is classified as Endangered by the IUCN. Given the limited information available about the species, we set out to assess marine otter diet with a view to detecting latitudinal differences, and to assess marine otter activity budgets and interspecific interactions (including anthropogenic) at Peruvian fishing villages and to compare results with similar Chilean studies. Nine study sites from central Chile to southern Peru were sampled for otter spraints to assess relative frequency of prey types and two fishing ports in southern Peru were monitored through focal and scan observations to assess activity patterns, interspecific interactions, habitat use patterns, and dive durations. Results indicate that toward the northern part of its range, crustaceans become less important and fish more important in the diet. Interactions were observed between marine otters and other species, including stray dogs and cats. The strong dependence of marine otters on the availability of safe rocky shelters, and the species' apparent tolerance to living alongside humans raise conservation concerns about vulnerability to anthropogenic threats. These factors, if not correctly managed, could turn some of these rocky seashore patches into population sinks. © 2010 by the Society for Marine Mammalogy.
Abstract.
Zbinden JA, Bearhop S, Bradshaw P, Gill B, Margaritoulis D, Newton J, Godley BJ (2011). Migratory dichotomy and associated phenotypic variation in marine turtles revealed by satellite tracking and stable isotope analysis.
Marine Ecology Progress Series,
421, 291-302.
Abstract:
Migratory dichotomy and associated phenotypic variation in marine turtles revealed by satellite tracking and stable isotope analysis
Linking foraging and breeding habitats is key to the understanding of behaviour, ecology and demography of migratory species Establishing such connections has long been hampered by the logistical problems of following individuals between foraging and breeding areas, especially in the marine realm We used variation in nitrogen stable isotope patterns between 2 foraging regions of loggerhead sea turtles Caretta caretta determined from samples of satellite-tracked individuals to assign untracked turtles to a foraging region We sought to enhance determination of the relative importance of geographically separated foraging regions and to investigate the relationship between fitness correlates and inferred migratory strategies of 18 turtles followed by satellite tracking from Zakynthos (Greece), 10 moved north to foraging areas in the Adriatic Sea and the Gulf of Amvrakikos and 8 moved south to foraging areas off the coast of North Africa of 51 untracked individuals sampled for stable isotope analysis, we considered the stable isotope signature of 47 to qualify for assignment to foraging areas in the north (n = 22) and south (n = 25) Females foraging north were significantly larger (curved carapace length), and the former group laid larger clutches (even after correction for body length) than turtles foraging south, a fact that can be interpreted as a carry-over effect Combining satellite tracking with stable isotope signatures in marine turtles opens new perspectives into how forensic tracking methodologies may be used to scale up knowledge from electronic tracking of a limited number of individuals to sample sizes that are more meaningful from a population perspective © Inter-Research 2011.
Abstract.
Mangel JC, Alfaro-Shigueto J, Witt MJ, Dutton PH, Seminoff JA, Godley BJ (2011). Post-capture movements of loggerhead turtles in the southeastern Pacific Ocean assessed by satellite tracking.
Marine Ecology Progress Series,
433, 261-272.
Abstract:
Post-capture movements of loggerhead turtles in the southeastern Pacific Ocean assessed by satellite tracking
The post-capture movements made by loggerhead sea turtles Caretta caretta in the southeastern Pacific Ocean were monitored from 2003 to 2007. Fourteen loggerhead turtles were fitted with satellite transmitters and released off the coast of Peru. All turtles were juveniles (curved carapace length range: 40.5 to 68.5 cm) incidentally captured by small-scale longline fishing vessels from southern or central Peru. Track durations were highly variable (mean ± SD: 143 ± 90 d; range: 8 to 297 d) with no clear signs of immediate post-release mortality. Upon release, all turtles moved offshore beyond the continental shelf. Eight of 11 turtles tracked for 750 km, suggesting that loggerhead turtles often maintain extended residency in these waters and that this area is an important foraging zone for loggerhead turtles of southwest Pacific origin. Satellite tracks also showed a substantial overlap of areas used by turtles with known Peruvian longline fishing effort. Turtles spent 75% of their time within the area fished by this fleet (based upon observed sets). This suggests that turtles are vulnerable to fishery interactions and that bycatch mitigation measures should be employed to minimize fishery impacts on loggerhead turtles. The loggerhead turtles tracked during this study spent ca. 51% of their time in Peruvian waters, 39% in international waters and 9% in Chilean waters, which emphasizes the need for a multinational approach to sea turtle conservation and fisheries management in the region. © 2011 Inter-Research.
Abstract.
Weber SB, Blount JD, Godley BJ, Witt MJ, Broderick AC (2011). Rate of egg maturation in marine turtles exhibits 'universal temperature dependence'.
J Anim Ecol,
80(5), 1034-1041.
Abstract:
Rate of egg maturation in marine turtles exhibits 'universal temperature dependence'.
1. The metabolic theory of ecology (MTE) predicts that, after correcting for body mass variation among organisms, the rates of most biological processes will vary as a universal function of temperature. However, empirical support for 'universal temperature dependence' (UTD) is currently equivocal and based on studies of a limited number of traits. 2. In many ectothermic animals, the rate at which females produce mature eggs is temperature dependent and may be an important factor in determining the costs of reproduction. 3. We tested whether the rate of egg maturation in marine turtles varies with environmental temperature as predicted by MTE, using the time separating successive clutches of individual females to estimate the rate at which eggs are formed. We also assessed the phenotypic contribution to this rate, by using radio telemetry to make repeated measurements of interclutch intervals for individual green turtles (Chelonia mydas). 4. Rates of egg maturation increased with seasonally increasing water temperatures in radio-tracked green turtles, but were not repeatable for individual females, and did not vary according to maternal body size or reproductive investment (number and size of eggs produced). 5. Using a collated data set from several different populations and species of marine turtles, we then show that a single relationship with water temperature explains most of the variation in egg maturation rates, with a slope that is statistically indistinguishable from the UTD predicted by MTE. However, several alternative statistical models also described the relationship between temperature and egg maturation rates equally parsimoniously. 6. Our results offer novel support for the MTE's predicted UTD of biological rates, although the underlying mechanisms require further study. The strong temperature dependence of egg maturation combined with the apparently weak phenotypic contribution to this rate has interesting behavioural implications in ectothermic animals. We suggest that maternal thermoregulatory behaviour in marine turtles, and many other reptiles, is consistent with a strategy of adaptively increasing body temperatures to accelerate egg maturation.
Abstract.
Author URL.
Alfaro-Shigueto J, Mangel JC, Bernedo F, Dutton PH, Seminoff JA, Godley BJ (2011). Small-scale fisheries of Peru: a major sink for marine turtles in the Pacific.
Journal of Applied Ecology,
48(6), 1432-1440.
Abstract:
Small-scale fisheries of Peru: a major sink for marine turtles in the Pacific
1. Over the last few decades, evidence of marine vertebrate bycatch has been collected for a range of industrial fisheries. It has recently been acknowledged that large impacts may also result from similar interactions with small-scale fisheries (SSF) due largely to their diffuse effort and large number of vessels in operation. Marine mammals, seabirds, turtles as well as some shark species have been reported as being impacted by SSF worldwide. 2. From 2000 to 2007, we used both shore-based and onboard observer programmes from three SSF ports in Peru to assess the impact on marine turtles of small-scale longline, bottom set nets and driftnet fisheries. 3. We reported a total of 807 sea turtles captured, 91·8% of which were released alive. For these three sites alone, we estimated c. 5900 turtles captured annually (3200 loggerhead turtles Caretta caretta, 2400 green turtles Chelonia mydas, 240 olive ridleys Lepidochelys olivacea and 70 leatherback turtles Dermochelys coriacea). 4.SSF in Peru are widespread and numerous (>100 ports, >9500 vessels, >37000 fishers), and our observed effort constituted c. 1% of longline and net deployments. We suggest that the number of turtles captured per year is likely to be in the tens of thousands. Thus, the impacts of Peruvian SSF have the potential to severely impact sea turtles in the Pacific especially green, loggerhead and leatherback turtles. 5. Implications of the human use of turtle products as 'marine bushmeat' are also raised as an important issue. Although such utilization is illegal, it is difficult to foresee how it can be managed without addressing the constraints to the livelihoods of those depending almost entirely on coastal resources. 6. Syntheses and applications. Our analysis demonstrates that, despite logistical challenges, it is feasible to estimate the bycatch per unit of effort in SSF by combining methods that account for fishing effort and bycatch, such as using onboard and shore-based observers. We highlight sea turtle bycatch in SSF in the southeast Pacific as a major conservation concern but also suggest possible paths for mitigation. © 2011 the Authors. Journal of Applied Ecology © 2011 British Ecological Society.
Abstract.
Witt MJ, Godley BJ, Broderick AC, Coyne MS (2011). Tracking leatherback turtles from the world's largest rookery: assessing threats across the South Atlantic.
Proceedings of the Royal Society BAbstract:
Tracking leatherback turtles from the world's largest rookery: assessing threats across the South Atlantic
Despite extensive work carried out on leatherback turtles (Dermochelys coriacea) in the North Atlantic and Indo-Pacific, very little is known of the at-sea distribution of this species in the South Atlantic, where the world's largest population nests in Gabon (central Africa). This paucity of data is of marked concern given the pace of industrialization in fisheries with demonstrable marine turtle bycatch in African/Latin American waters. We tracked the movements of 25 adult female leatherback turtles obtaining a range of fundamental and applied insights, including indications for methodological advancement. Individuals could be assigned to one of three dispersal strategies, moving to (i) habitats of the equatorial Atlantic, (ii) temperate habitats off South America or (iii) temperate habitats off southern Africa. While occupying regions with high surface chlorophyll concentrations, these strategies exposed turtles to some of the world's highest levels of longline fishing effort, in addition to areas with coastal gillnet fisheries. Satellite tracking highlighted that at least 11 nations should be involved in the conservation of this species in addition to those with distant fishing fleets. The majority of tracking days were, however, spent in the high seas, where effective implementation of conservation efforts is complex to achieve.
Abstract.
Humber F, Godley BJ, Ramahery V, Broderick AC (2011). Using community members to assess artisanal fisheries: the marine turtle fishery in Madagascar. Animal Conservation(14), 175-185.
Maxwell SM, Breed GA, Nickel BA, Makanga-Bahouna J, Pemo-Makaya E, Parnell RJ, Formia A, Ngouessono S, Godley BJ, Costa DP, et al (2011). Using satellite tracking to optimize protection of long-lived marine species: olive ridley sea turtle conservation in Central Africa.
PLoS One,
6(5).
Abstract:
Using satellite tracking to optimize protection of long-lived marine species: olive ridley sea turtle conservation in Central Africa.
Tractable conservation measures for long-lived species require the intersection between protection of biologically relevant life history stages and a socioeconomically feasible setting. To protect breeding adults, we require knowledge of animal movements, how movement relates to political boundaries, and our confidence in spatial analyses of movement. We used satellite tracking and a switching state-space model to determine the internesting movements of olive ridley sea turtles (Lepidochelys olivacea) (n = 18) in Central Africa during two breeding seasons (2007-08, 2008-09). These movements were analyzed in relation to current park boundaries and a proposed transboundary park between Gabon and the Republic of Congo, both created to reduce unintentional bycatch of sea turtles in marine fisheries. We additionally determined confidence intervals surrounding home range calculations. Turtles remained largely within a 30 km radius from the original nesting site before departing for distant foraging grounds. Only 44.6 percent of high-density areas were found within the current park but the proposed transboundary park would incorporate 97.6 percent of high-density areas. Though tagged individuals originated in Gabon, turtles were found in Congolese waters during greater than half of the internesting period (53.7 percent), highlighting the need for international cooperation and offering scientific support for a proposed transboundary park. This is the first comprehensive study on the internesting movements of solitary nesting olive ridley sea turtles, and it suggests the opportunity for tractable conservation measures for female nesting olive ridleys at this and other solitary nesting sites around the world. We draw from our results a framework for cost-effective protection of long-lived species using satellite telemetry as a primary tool.
Abstract.
Author URL.
Leeney RH, Broderick AC, Mills C, Sayer S, Witt MJ, Godley BJ (2010). Abundance, distribution and haul-out behaviour of grey seals (Halichoerus grypus) in Cornwall and the Isles of Scilly, UK.
Journal of the Marine Biological Association of the United Kingdom,
90(5), 1033-1040.
Abstract:
Abundance, distribution and haul-out behaviour of grey seals (Halichoerus grypus) in Cornwall and the Isles of Scilly, UK
This study investigated the phenology, patterns of haul-out habitat use and distribution of the grey seal around Cornwall and the Isles of Scilly. A full census of the coast was carried out by boat over 4 days, in order to make a full count of seals hauled out and close to the coast, and to document all haul-out sites. Regular land-based surveys were made of three haul-out sites in Cornwall, to investigate the effects of spatial, temporal and environmental factors on seal haul-out behaviour. Data from 2004 to 2007 were analysed to describe long-term temporal variation in seal abundance at two haul-out sites. A total of 592 sightings were made along the coast of Cornwall and the Isles of Scilly over the four-day census period; 476 of these sightings (80.4%) were recorded at six main haul-out sites. The highest proportion of seals was observed at three haul-out areas on the Isles of Scilly. In Cornwall, seals were observed in higher numbers on the north coast, where the three largest mainland haul-out sites were documented, than on the south coast. At one key haul-out site in Cornwall, a distinct seasonal pattern was evident in data collected between 2004 and 2007, with higher numbers of seals present during the moulting and breeding seasons than over the summer months. There was considerable inter-annual variability in peak seal abundance, during the moulting season, at this site. There was no significant variation in haul-out behaviour with tidal state at this site, although haul-out counts were generally highest at mid-ebb tides. Data on seal abundance, distribution and haul-out behaviour may aid the designation of Special Areas of Conservation for the protection of grey seals in Cornwall and the Isles of Scilly. © 2010 Marine Biological Association of the United Kingdom.
Abstract.
Witt MJ, Åkesson S, Broderick AC, Coyne MS, Ellick J, Formia A, Hays GC, Luschi P, Stroud S, Godley BJ, et al (2010). Assessing accuracy and utility of satellite-tracking data using Argos-linked Fastloc-GPS. Animal Behaviour, 80(3), 571-581.
Rees AF, Al Saady S, Broderick AC, Coyne MS, Papathanasopoulou N, Godley BJ (2010). Behavioural polymorphism in one of the world's largest populations of loggerhead sea turtles Caretta caretta.
Marine Ecology Progress Series,
418, 201-212.
Abstract:
Behavioural polymorphism in one of the world's largest populations of loggerhead sea turtles Caretta caretta
To aid management and conservation of widely distributed marine vertebrate species, it is necessary to have a knowledge and understanding of their spatial ecology. We tracked 10 adult female loggerhead turtles Caretta caretta from Masirah Island, Sultanate of Oman, which hosts one of the world's largest breeding aggregations. Transmitters were specifically deployed early in the nesting season to enable tracking throughout the internesting and post-nesting habitats. Turtles displayed a dichotomy in behaviour during the internesting period, with 6 remaining close to Masirah Island and the others undertaking circuitous oceanic loops, hundreds of kilometres in length. This behaviour did not appear to be related to body size. Tracking-derived minimum clutch frequency was on average (± SD) 4.8 ±1.2 nests (n = 8 ind.). Post-nesting migrations revealed a propensity towards long-term utilisation of oceanic habitats in the region between Socotra Island (Yemen) and the mainland of Yemen/Oman, with 76 ± 15.4% of time spent in oceanic habitat (n = 8 ind.). The spatial footprint of our tracked turtles was found to be far less than that of a similar number of turtles that were tagged later in the same season (from a separate unpublished study) and from long-distance returns of flipper tags. The spatial and temporal sub-structuring of the population highlights the need for more comprehensive tracking projects, with deployments across the breeding season in multiple years, in order to obtain reliable estimations of high-use foraging habitats of widely dispersed marine vertebrates. Variation in behaviour patterns suggests the need for diverse conservation measures. © Inter-Research 2010.
Abstract.
Tomás J, Godley BJ, Castroviejo J, Raga JA (2010). Bioko: Critically important nesting habitat for sea turtles of West Africa.
Biodiversity and Conservation,
19(9), 2699-2714.
Abstract:
Bioko: Critically important nesting habitat for sea turtles of West Africa
We evaluate the conservation status and threats faced by sea turtle nesting populations at Bioko Island, Equatorial Guinea (Central Africa). Beaches were monitored to obtain a detailed sea turtle nest census and, where possible, tagging of adult females was undertaken. Four sea turtle species were found nesting in the area: the green turtle (Chelonia mydas), the leatherback (Dermochelys coriacea), the olive ridley (Lepidochelys olivacea) and the hawksbill (Eretmochelys imbricata); with the former two species nesting in regionally important numbers. Nesting activity was concentrated between November and February, with a peak in December-January. Tagging and recapture of green turtles in two consecutive seasons suggested an estimated 560 (interquartile range: 420-1,681) and 414 (interquartile range: 190-1,255) nesting females in the area, respectively. Estimated numbers of nesting leatherbacks ranged from 123 to 215 and 243 to 293 in the first and second season, respectively. The other two species were less abundant (olive ridley: 19-29 and 28-43; hawksbill: 4-10 and 2 turtles). Data were compared with more recent surveys in the area and contextualised with information on human related threats. Despite the size of nesting stocks, ongoing permitted and illegal take of adult turtles at the nesting site constitutes a serious threat for these breeding aggregations. Additionally, tag returns from throughout the Gulf of Guinea suggest that the level of take in regional fisheries may also be a major threat. © 2010 Springer Science+Business Media B.V.
Abstract.
Bograd SJ, Block BA, Costa DP, Godley BJ (2010). Biologging technologies: New tools for conservation. Introduction.
Endangered Species Research,
10(1), 1-7.
Abstract:
Biologging technologies: New tools for conservation. Introduction
Biologging technology allows researchers to take measurements from free-ranging animals as they move undisturbed through their environment. Recent advances in biologging technology, including electronic tag miniaturization and improved animal movement models, have revolutionized our understanding of the ecology of top predators and have permitted observations well beyond the reach of standard measurement techniques. Engineering has provided the biologging community with ever more sophisticated tags, and advances in the application of statistical methods to interpret these data have yielded powerful new tools for understanding animal behavior. The technology has also reached sufficient sophistication and reliability such that the data collected is often equivalent to industry standards for environmental sampling, which has led to profound advancements in the marine realm, where the sheer vastness, in 3 dimensions, limits our ability to observe. Biologging data is now being increasingly applied to marine management and conservation policy. In this introduction, we highlight a few of the research themes presented at the Third International Conference on Biologging Science, and comment on the future challenges of biologging science. © Inter-Research 2010.
Abstract.
Hamann M, Godfrey MH, Seminoff JA, Arthur K, Barata PCR, Bjorndal KA, Bolten AB, Broderick AC, Campbell LM, Carreras C, et al (2010). Global research priorities for sea turtles: Informing management and conservation in the 21st century.
Endangered Species Research,
11(3), 245-269.
Abstract:
Global research priorities for sea turtles: Informing management and conservation in the 21st century
Over the past 3 decades, the status of sea turtles and the need for their protection to aid population recovery have increasingly captured the interest of government agencies, non-governmental organisations (NGOs) and the general public worldwide. This interest has been matched by increased research attention, focusing on a wide variety of topics relating to sea turtle biology and ecology, together with the interrelations of sea turtles with the physical and natural environments. Although sea turtles have been better studied than most other marine fauna, management actions and their evaluation are often hindered by the lack of data on turtle biology, human-turtle interactions, turtle population status and threats. In an effort to inform effective sea turtle conservation a list of priority research questions was assembled based on the opinions of 35 sea turtle researchers from 13 nations working in fields related to turtle biology and/or conservation. The combined experience of the contributing researchers spanned the globe as well as many relevant disciplines involved in conservation research. An initial list of more than 200 questions gathered from respondents was condensed into 20 metaquestions and classified under 5 categories: reproductive biology, biogeography, population ecology, threats and conservation strategies. © Inter-Research 2010.
Abstract.
Witt MJ, McGowan A, Blumenthal JM, Broderick AC, Gore S, Wheatley D, White J, Godley BJ (2010). Inferring vertical and horizontal movements of juvenile marine turtles from time-depth recorders.
AQUATIC BIOLOGY,
8(2), 169-177.
Author URL.
Bell CD, Blumenthal JM, Broderick AC, Godley BJ (2010). Investigating potential for depensation in marine turtles: How low can you Go?: Contributed paper.
Conservation Biology,
24(1), 226-235.
Abstract:
Investigating potential for depensation in marine turtles: How low can you Go?: Contributed paper
Where mechanisms inherent within the biology of a species affect individual fitness at low density, demographic-scale depensation may occur, hastening further decline and leading ultimately to population extirpation and species extinction. Reduction in fertility at low population densities has been identified in marine and terrestrial species. Using data on hatch success and hatchling-emergence success as proxies for fertilization success, we conducted a global meta-analysis of data from breeding aggregations of green turtles (Chelonia mydas) and loggerhead turtles (Caretta caretta). We found that there has been no reduction in fertility in small nesting aggregations in either of these species worldwide. We considered mechanisms within the mating strategies and reproductive biology of marine turtles that may allow for novel genetic input and facilitate enhanced gene flow among rookeries. Behavioral reproductive mechanisms, such as natal philopatry and polyandry, may mitigate potential impacts of depensation and contribute to the resilience of these species. © 2009 Society for Conservation Biology.
Abstract.
Bell CD, Blumenthal JM, Broderick AC, Godley BJ (2010). Investigating potential for depensation in marine turtles: how low can you go?.
Conserv Biol,
24(1), 226-235.
Abstract:
Investigating potential for depensation in marine turtles: how low can you go?
Where mechanisms inherent within the biology of a species affect individual fitness at low density, demographic-scale depensation may occur, hastening further decline and leading ultimately to population extirpation and species extinction. Reduction in fertility at low population densities has been identified in marine and terrestrial species. Using data on hatch success and hatchling-emergence success as proxies for fertilization success, we conducted a global meta-analysis of data from breeding aggregations of green turtles (Chelonia mydas) and loggerhead turtles (Caretta caretta). We found that there has been no reduction in fertility in small nesting aggregations in either of these species worldwide. We considered mechanisms within the mating strategies and reproductive biology of marine turtles that may allow for novel genetic input and facilitate enhanced gene flow among rookeries. Behavioral reproductive mechanisms, such as natal philopatry and polyandry, may mitigate potential impacts of depensation and contribute to the resilience of these species.
Abstract.
Author URL.
Blumenthal JM, Austin TJ, Bothwell JB, Broderick AC, Ebanks-Petrie G, Olynik JR, Orr MF, Solomon JL, Witt MJ, Godley BJ, et al (2010). Life in (and out of) the lagoon: Fine-scale movements of green turtles tracked using time-depth recorders.
Aquatic Biology,
9(2), 113-121.
Abstract:
Life in (and out of) the lagoon: Fine-scale movements of green turtles tracked using time-depth recorders
Tracking fine-scale movements in relation to threats is fundamental to the management of exploited marine species, yet there is considerable difficulty associated with gathering such data at sea. By combining a capture-recapture study with deployment of time-depth recorders (TDRs) and ultrasonic tags, we elucidated distribution and daily movements of juvenile green turtles Chelonia mydas exposed to a legal marine turtle fishery in the Cayman Islands. For instrumented turtles, distinct diel activity patterns were observed: dives during the day were shorter and more active than those at night, implying diurnal foraging and nocturnal resting. Spatially, while capture and recapture locations suggested fidelity to a shallow lagoon, when turtles were fitted with TDRs and ultra-sonic tags we demonstrated that they regularly moved out of the lagoon and onto the reef, where they could legally be captured in the marine turtle fishery. Our results are thus novel and valuable in a management context in that we demonstrated that seemingly protected aggregations of juvenile green turtles within a lagoon were, in fact, exposed to legal capture on a near-daily basis. This emphasizes the importance of assessing diel activity patterns of juvenile marine turtles, particularly with respect to directed take and other threats. © Inter-Research 2010.
Abstract.
Fuller WJ, Broderick AC, Enever R, Thorne P, Godley BJ (2010). Motile homes: a comparison of the spatial distribution of epibiont communities on Mediterranean sea turtles.
Journal of Natural History,
44(27), 1743-1753.
Abstract:
Motile homes: a comparison of the spatial distribution of epibiont communities on Mediterranean sea turtles
Understanding the ecological roles performed by an individual species requires knowledge from a wide range of disciplines; here we analyze the epibiont-host relationship found in marine turtles. During the study we recorded five new species of sea turtle epibiont: Laomedea flexuosa, Caprella fretensis, Hyale nilssoni, Hyale schmidti, Parasinelobus chevreuxi; as part of a total of nine zoological epibionts present on 35 female green turtles (Chelonia mydas) and 100 loggerhead turtles (Caretta caretta) nesting in Cyprus. The two most commonly occurring epibionts were acorn barnacles Chelonibia testudinaria and Chelonibia caretta, with larger specimens of both species recorded on loggerhead turtles. We analyzed the spatial distribution of these two barnacle species upon the carapaces of their hosts. Specimens of C. testudinaria situated on the anterior half of the carapace were larger than those located at the posterior. A significantly larger proportion of loggerhead turtles (152.5%) hosted epibionts in comparison to green turtles (30.3%). All non-barnacle epibionts were associated with either posterior algal mats or carapace scars. © 2010 Taylor & Francis.
Abstract.
Fuller WJ, Broderick AC, Enever R, Thorne P, Godley BJ (2010). Motile homes: a comparison of the spatial distribution of epibiont communities on Mediterranean sea turtles.
JOURNAL OF NATURAL HISTORY,
44(27-28), 1743-1753.
Author URL.
Grecian WJ, Inger R, Attrill MJ, Bearhop S, Godley BJ, Witt MJ, Votier SC (2010). Potential impacts of wave-powered marine renewable energy installations on marine birds.
Ibis,
152, 683-697.
Abstract:
Potential impacts of wave-powered marine renewable energy installations on marine birds
One potential approach to combat the impacts of climate change is the expansion of renewable energy installations, leading to an increase in the number of wave-powered marine renewable energy installations (MREIs). The consequences of increased use of these devices for birds are unknown. Here we describe the wave-powered energy- generating devices currently either operational or in development and review the potential threats and benefits of these to marine birds, their habitats and prey. Direct neg- ative effects include risk of collision, disturbance, displacement and redirection during construction, operation and decommissioning. Above-water collision is a particular con- cern with wind-powered devices, but, because of their low profiles, the collision risk asso- ciated with wave-powered devices is likely to be much lower. Conversely, wave devices also pose the novel threat of underwater collision. Wave-energy-generating devices may indirectly impact marine birds by altering oceanographic processes and food availability, with implications for trophic cascades. Through appropriate mitigation, wave-powered MREIs offer the potential to enhance habitats. Direct positive effects may include provision of roosting sites, and indirect positive effects may include prey aggregation due to suitable substrates for sessile organisms or because they act as de facto protected areas. The cumulative effect of these could be the improvement and protection of foraging opportunities for marine birds. Recent studies have been critical of the methods used in the assessment of wind-powered MREI impacts, which lack sufficient sample sizes, controls or pre-development comparisons. Here we suggest solutions for the design of future studies into the effects of MREIs. Wave-powered MREIs are certain to become part of the marine environment, but with appropriate planning, mitigation and monitor- ing they have the potential to offer benefits to marine birds in the future.
Abstract.
Witt MJ, Hawkes LA, Godfrey MH, Godley BJ, Broderick AC (2010). Predicting the impacts of climate change on a globally distributed species: the case of the loggerhead turtle.
J Exp Biol,
213(6), 901-911.
Abstract:
Predicting the impacts of climate change on a globally distributed species: the case of the loggerhead turtle.
Marine turtles utilise terrestrial and marine habitats and several aspects of their life history are tied to environmental features that are altering due to rapid climate change. We overview the likely impacts of climate change on the biology of these species, which are likely centred upon the thermal ecology of this taxonomic group. Then, focusing in detail on three decades of research on the loggerhead turtle (Caretta caretta L.), we describe how much progress has been made to date and how future experimental and ecological focus should be directed. Key questions include: what are the current hatchling sex ratios from which to measure future climate-induced changes? What are wild adult sex ratios and how many males are necessary to maintain a fertile and productive population? How will climate change affect turtles in terms of their distribution?
Abstract.
Author URL.
Hartnoll RG, Broderick AC, Godley BJ, Musick S, Pearson M, Stroud SA, Saunders KE (2010). Reproduction in the land crab Johngarthia lagostoma on Ascension Island.
Journal of Crustacean Biology,
30(1), 83-92.
Abstract:
Reproduction in the land crab Johngarthia lagostoma on Ascension Island
Reproduction was studied in the land crab Johngarthia lagostoma on Ascension Island in the central South Atlantic from 2005 to 2008. Both sexes are mature by 60-70 mm carapace width (the sample > 4,000 crabs consisted almost entirely of mature specimens). Breeding occurs around the east and south shores of the island, but was studied predominantly at the only easily accessible site at North East Bay. The annual breeding migration extends from January to May, with peak migration in March in most years. The intensity of migration varies between years, and is not obviously related to rainfall. There is lunar entrainment, with increased numbers at the shore in the first quarter, but largest numbers in the last quarter. Both males and females migrate, but with females in greater numbers. At the shore 80 of the crabs are females. A few females mate and lay eggs in the upland residential areas, a greater number do so on the migration route, but the majority only after reaching the shore. Reproductive investment per brood averaged 5% on a dry weight basis, and fecundity averaged 72,000 eggs. © 2010 the Crustacean Society.
Abstract.
Mangel JC, Alfaro-Shigueto J, Van Waerebeek K, Cáceres C, Bearhop S, Witt MJ, Godley BJ (2010). Small cetacean captures in Peruvian artisanal fisheries: High despite protective legislation.
Biological Conservation,
143(1), 136-143.
Abstract:
Small cetacean captures in Peruvian artisanal fisheries: High despite protective legislation
We detail the first direct, at sea monitoring of small cetacean interactions with Peruvian artisanal drift gillnet and longline fisheries. A total of 253 small cetaceans were captured during 66 monitored fishing trips (Gillnet: 46 trips; Longline: 20 trips) from the port of Salaverry, northern Peru (8o14′S, 78o59′W) from March 2005 to July 2007. The most commonly captured species were common dolphins (Delphinus spp.) (47%), dusky dolphins (Lagenorhynchus obscurus) (29%), common bottlenose dolphins (Tursiops truncatus) (13%) and Burmeister's porpoises (Phocoena spinipinnis) (6%). An estimated 95% of common dolphin bycatch was of long-beaked common dolphins (Delphinus capensis). Overall bycatch per unit effort for gillnet vessels (mean ± sd) was estimated to be 0.65 ± 0.41 animals.set-1 (range 0.05-1.50) and overall catch (bycatch and harpoon) was 4.96 ± 3.33 animals.trip-1 (range 0.33-13.33). Based upon total fishing effort for Salaverry we estimated the total annual average small cetacean bycatch by gillnet vessels as 2412 animals.year-1 (95% CI 1092-4303) for 2002-2007. This work indicates that, in at least one Peruvian port, bycatch and harpooning of small cetaceans persist at high levels and on a regular basis, particularly in driftnet vessels, despite the existence since the mid-1990s of national legislation banning the capture of marine mammals and commerce in their products. It is concluded that the coast of Peru is likely still one of the world's principal areas for concern regarding high small cetacean bycatch and there is clearly an urgent need to increase the geographic scope of observer effort to elucidate the full magnitude of this issue. © 2009 Elsevier Ltd. All rights reserved.
Abstract.
Ratcliffe N, Bell M, Pelembe T, Boyle D, Benjamin R, White R, Godley B, Stevenson J, Sanders S (2010). The eradication of feral cats from Ascension Island and its subsequent recolonization by seabirds.
ORYX,
44(1), 20-29.
Abstract:
The eradication of feral cats from Ascension Island and its subsequent recolonization by seabirds
The introduction of mammal predators to islands often results in rapid declines in the number and range of seabirds. On Ascension Island the introduction of cats in 1815 resulted in extirpation of large seabird colonies from the main island, with relict populations of most species persisting only in cat-inaccessible locations. We describe the eradication of feral cats from this large and populated island. The campaign had to minimize risk to humans and maintain domestic animals in a state that prevented them re-establishing a feral population. Feral cat numbers declined rapidly in response to the strategic deployment of poisoning and live trapping, and cats were eradicated from the island within 2 years. During the project 38% of domestic cats were killed accidentally, which caused public consternation; we make recommendations for reducing such problems in future eradications. Since the completion of the eradication campaign cat predation of adult seabirds has ceased and five seabird species have recolonized the mainland in small but increasing numbers. Breeding success of seabirds at Ascension was low compared to that of conspecifics elsewhere, and the roles of food availability, inexperience of parent birds and black rat predation in causing this warrant further investigation. It is likely that the low breeding success will result in the rate of increase in seabird populations being slow. © 2009 Fauna & Flora International.
Abstract.
Godley BJ, Barbosa C, Bruford M, Broderick AC, Catry P, Coyne MS, Formia A, Hays GC, Witt MJ (2010). Unravelling migratory connectivity in marine turtles using multiple methods.
Journal of Applied Ecology,
47(4), 769-778.
Abstract:
Unravelling migratory connectivity in marine turtles using multiple methods
Comprehensive knowledge of the fundamental spatial ecology of marine species is critical to allow the identification of key habitats and the likely sources of anthropogenic threats, thus informing effective conservation strategies. Research on migratory marine vertebrates has lagged behind many similar terrestrial animal groups, but studies using electronic tagging systems and molecular techniques offer great insights. Marine turtles have complex life history patterns, spanning wide spatio-temporal scales. As a result of this multidimensional complexity, and despite extensive effort, there are no populations for which a truly holistic understanding of the spatial aspects of the life history has been attained. There is a particular lack of information regarding the distribution and habitats utilized during the first few years of life. We used satellite tracking technology to track individual turtles following nesting at the green turtle Chelonia mydas nesting colony at Poilão Island, Guinea Bissau; the largest breeding aggregation in the eastern Atlantic. We further contextualize these data with pan-Atlantic molecular data and oceanographic current modelling to gain insights into likely dispersal patterns of hatchlings and small pelagic juveniles. All adult turtles remained in the waters of West Africa, with strong connectivity demonstrated with Banc D'Arguin, Mauritania. Despite shortcomings in current molecular markers, we demonstrate evidence for profound sub-structuring of marine turtle stocks across the Atlantic; with a high likelihood based on oceanographic modelling that most turtles from Guinea-Bissau are found in the eastern Atlantic. Synthesis and applications. There is an increased need for a better understanding of spatial distribution of marine vertebrates demonstrating life histories with spatio-temporal complexity. We propose the synergistic use of the technologies and modelling used here as a working framework for the future rapid elucidation of the range and likely key habitats used by the different life stages from such species. © 2010 the Authors. Journal compilation © 2010 British Ecological Society.
Abstract.
Alfaro-Shigueto J, Mangel JC, Pajuelo M, Dutton PH, Seminoff JA, Godley BJ (2010). Where small can have a large impact: Structure and characterization of small-scale fisheries in Peru.
Fisheries Research,
106(1), 8-17.
Abstract:
Where small can have a large impact: Structure and characterization of small-scale fisheries in Peru
Small-scale fisheries in Peru constitute an important source of food and employment for coastal communities where fish is the single most important natural resource. Utilizing official statistics and extensive survey data from 30 fishing ports and by onboard observers operating from 11 ports, we review how these fisheries grew from 1995 to 2005, and provide insights into the relative importance of different fishing gears and their modes of operation. Small-scale fisheries operate along the entire Peruvian coast and have continued expanding in number of vessels and fishers in all geopolitical regions except one. Nationwide, the number of fishers grew by 34% from 28. 098 to 37. 727 and the number of vessels increased by 54% from 6268 to 9667. At 30 harbors, the number of vessels increased for purse seiners (17.8%) and longliners (357.4%), while gillnets decreased (-14.5%). These dramatic changes could jeopardize the sustainability of these fisheries and the livelihoods of those who depend upon them, especially considering the limited capacity for management. Despite increase in effort, catch and catch per vessel have decreased, especially in some of the sub-regions that previously constituted the majority of effort and landings, raising concerns regarding their sustainability. of the fishing gears monitored, gillnets were shown to have the most frequent interactions with threatened taxa such as marine mammals, seabirds and sea turtles. The total length of gillnets set in Peru was estimated at >100. 000. km of net per year, about 14 times the length used by the Taiwanese high seas driftnet fleet in the Pacific before it was banned. Longlines, although shown to be a more efficient fishing method (economically and in terms of selectivity), still had bycatch of turtles and seabirds, and marine mammals are targeted to be used as bait. We conservatively estimate that longline vessels operating in Peru set an average of 80 million hooks per year; equivalent to one-third of the annual effort of the global industrial swordfish longline fishery. We conclude that, despite their definition as small-scale, the magnitude of these fleets and their fishing effort are vast and are of concern with regard to their long term sustainability and their impacts and interactions with large marine vertebrates. We highlight the need for increased research and management measures to ensure the long term viability of these fisheries. © 2010 Elsevier B.V.
Abstract.
Witt MJ, Baert B, Broderick AC, Formia A, Fretey J, Gibudi A, Mounguengui GAM, Moussounda C, Ngouessono S, Parnell RJ, et al (2009). Aerial surveying of the world's largest leatherback turtle rookery: a more effective methodology for large-scale monitoring.
Biological Conservation,
142(8), 1719-1727.
Abstract:
Aerial surveying of the world's largest leatherback turtle rookery: a more effective methodology for large-scale monitoring
For many marine megavertebrate species it is challenging to derive population estimates and knowledge on habitat use needed to inform conservation planning. For marine turtles, the logistics required to undertake comprehensive ground-based censuses, across wide spatial and temporal scales, are often insurmountable. This frequently leads to an approach where a limited number of index nesting beaches are monitored in great detail by foot. In this study we use nationwide aerial surveying interfaced with ground assessments across three seasons of leatherback turtle nesting in Gabon (Equatorial West Africa), highlighting the importance of a synoptic approach to marine turtle monitoring. These surveys allow the first complete population assessment of this nesting aggregation to be made, identifying it as the world's largest for the species (36,185-126,480 clutches, approximating to 5865-20,499 breeding females per annum and a total estimate of 15,730 to 41,373 breeding females). Our approach also serendipitously provides insights into the spatial appropriateness of Gabon's protected areas network, for example (mean ± 1SD) 79 ± 6% (range 67-86%) of leatherback turtle activities recorded during aerial surveys (n = 8) occurred within protected areas (345 km, 58%, of surveyed coastline). We identify and discuss sources of potential error in estimating total nesting effort from aerial surveying techniques and show that interannual variation in nesting is considerable, which has implications for the detection of statistically significant changes in population size. Despite its relative costliness per day, aerial surveying can play an important role in providing estimates of relative population abundance of large vertebrates dispersed over extensive areas. Furthermore, it can provide data on habitat use and deliver real-time information on the spatial efficacy of protected area networks. © 2009 Elsevier Ltd. All rights reserved.
Abstract.
Hawkes LA, Broderick AC, Godfrey MH, Godley BJ (2009). Climate change and marine turtles.
Endangered Species Research,
7(2), 137-154.
Abstract:
Climate change and marine turtles
Marine turtles occupy a wide range of terrestrial and marine habitats, and many aspects of their life history have been demonstrated to be closely tied to climatic variables such as ambient temperature and storminess. As a group, therefore, marine turtles may be good indicators of climate change effects on coastal and marine habitats. Despite the small number of species in the taxon and a growing body of research in the field, the evidence base to predict resultant impacts of climate change remains relatively poor. We review the data from peer-reviewed publications to assess the likely impacts of climate change on marine turtles and highlight the types of data that would be most useful for an accurate assessment of future effects. The cumulative indications from these previous studies indicate that future research should focus on: (1) climate change effects on key habitats upon which turtles depend; (2) factors that influence nest site selection; (3) the consequences of skewed primary sex ratios; and (4) the effect of climate change on turtles at sea, for example range shifts and dietary breadth. Although it is too early to give detailed management recommendations, careful protection of coastlines along which turtles nest should be considered, as should the protection of beaches that produce male hatchlings, which may be of increased importance in the future. More active management approaches, for example translocation of eggs to suitable yet vacant nesting beaches, may be necessary to consider under worst-case scenarios. © Inter-Research 2009.
Abstract.
Campbell LM, Silver JJ, Gray NJ, Ranger S, Broderick AC, Fisher T, Godfrey MH, Gore S, Hodge KVD, Jeffers J, et al (2009). Co-management of sea turtle fisheries: Biogeography versus geopolitics. Marine Policy, 33, 137-145.
Blumenthal JM, Austin TJ, Bothwell JB, Broderick AC, Ebanks-Petrie G, Olynik JR, Orr MF, Solomon JL, Witt MJ, Godley BJ, et al (2009). Diving behavior and movements of juvenile hawksbill turtles Eretmochelys imbricata on a Caribbean coral reef.
Coral Reefs,
28(1), 55-65.
Abstract:
Diving behavior and movements of juvenile hawksbill turtles Eretmochelys imbricata on a Caribbean coral reef
As historically abundant spongivores, hawksbill turtles Eretmochelys imbricata likely played a key ecological role on coral reefs. However, coral reefs are now experiencing global declines and many hawksbill populations are critically reduced. For endangered species, tracking movement has been recognized as fundamental to management. Since movements in marine vertebrates encompass three dimensions, evaluation of diving behavior and range is required to characterize marine turtle habitat. In this study, habitat use of hawksbill turtles on a Caribbean coral reef was elucidated by quantifying diel depth utilization and movements in relation to the boundaries of marine protected areas. Time depth recorders (TDRs) and ultrasonic tags were deployed on 21 Cayman Islands hawksbills, ranging in size from 26.4 to 58.4 cm straight carapace length. Study animals displayed pronounced diel patterns of diurnal activity and nocturnal resting, where diurnal dives were significantly shorter, deeper, and more active. Mean diurnal dive depth (±SD) was 8 ± 5 m, range 2-20 m, mean nocturnal dive depth was 5 ± 5 m, range 1-14 m, and maximum diurnal dive depth was 43 ± 27 m, range 7-91 m. Larger individuals performed significantly longer dives. Body mass was significantly correlated with mean dive depth for nocturnal but not diurnal dives. However, maximum diurnal dive depth was significantly correlated with body mass, suggesting partitioning of vertical habitat by size. Thus, variable dive capacity may reduce intraspecific competition and provide resistance to degradation in shallow habitats. Larger hawksbills may also represent important predators on deep reefs, creating a broad ecological footprint over a range of depths. © 2008 Springer-Verlag.
Abstract.
Blumenthal JM, Austin TJ, Bell CDL, Bothwell JB, Broderick AC, Ebanks-Petrie G, Gibb JA, Luke KE, Olynik JR, Orr ME, et al (2009). Ecology of hawksbill turtles, Eretmochelys imbricata, on a western caribbean foraging ground.
Chelonian Conservation and Biology,
8(1), 1-10.
Abstract:
Ecology of hawksbill turtles, Eretmochelys imbricata, on a western caribbean foraging ground
We present results of an inwater research program focusing on basic ecology of juvenile hawksbill turtles (Eretmochelys imbricata) in the Cayman Islands. We made 206 captures of 135 hawksbills in Little Cayman and 103 captures of 97 hawksbills in Grand Cayman. The Cayman Islands aggregation demonstrated a broad size distribution (20.5-62.6 cm straight carapace length), slow growth rate (3.0 ± 0.9 cm/y), and multiple recaptures, suggesting long-term residence in some individuals. Demonstrated home range was small (mean distance from capture to recapture 545 ± 514 m, range 2-2080 m); although, an international tag return suggested a long-range developmental migration. Vertical features provided important habitat in Little Cayman, and larger turtles were generally captured in deeper waters. Behavior at sighting varied by habitat: resting, swimming, and feeding were observed in coral reef, reef wall, and hardbottom colonized by sponges and gorgonians, and resting was frequently observed in uncolonized hardbottom. Images obtained from underwater photographers show that hawksbills forage on sponges and occasionally on jellyfish. We observed an apparent commensal feeding relationship between hawksbills and 3 species of angelfish as well as aggressive interactions between hawksbills. We also documented causes of injury and mortality in the study area-including legal, illegal and incidental take, vessel collisions, hurricanes, and natural predation. © 2009 ChelonIan Research Foundation.
Abstract.
Godley BJ (2009). Forensic methods in conservation research. Endangered Species Research, 9(3), 167-168.
Pintus KJ, Godley BJ, McGowan A, Broderick AC (2009). Impact of clutch relocation on green turtle offspring.
Journal of Wildlife Management,
73(7), 1151-1157.
Abstract:
Impact of clutch relocation on green turtle offspring
For species with temperature-dependent sex determination, such as marine turtles, global climate change poses numerous threats. At the nesting beach, rising temperatures are predicted to further skew already female-biased sex ratios and increase embryonic mortality; sea-level rise and resultant coastal squeeze may leave few alternative breeding habitats in developed regions. As a result, clutch relocation, a commonly used management tool to reduce egg loss, may become necessary for safeguarding populations. Although studies have examined the impact of relocation on clutch success, few have examined the impact of this practice on the sex or phenotypic characteristics of hatchlings produced. We used a randomized block design experiment to examine effects of relocation on green turtle (Chelonia mydas) clutches. We compared hatching success, thermal conditions, and size (length and mass) of hatchlings from in situ control clutches with those subjected to 2 relocation methods, while controlling for maternal and other environmental effects. Relocated clutches did not vary significantly from control clutches in incubation temperature or inferred sex ratios during the critical middle third of incubation when sex is thought to be determined. Hatchling size was also unaffected by relocation. Both relocation methods, however, resulted in a 20 reduction in hatching success in comparison to in situ clutches. Clutch relocation is, however, likely to affect the population primary sex ratio, when clutches are relocated from sites in proximity to the sea where tidal inundation is a threat. Here, cooler conditions are likely to produce more males than are the warmer female-producing temperatures higher up the beach. For clutches at risk, relocation is a viable process and does not appear to affect hatchling size or predicted sex ratios if relocation sites are selected in areas utilized by other females. We urge caution, however, when moving clutches from potentially male-producing sites, particularly given predicted impacts of climate change on already female-biased sex ratios. © 2009 the Wildlife Society.
Abstract.
Godley BJ (2009). Incorporating climate change into endangered species conservation: Introduction. Endangered Species Research, 7(2), 85-86.
Fuller WJ, Broderick AC, Hooker SK, Witt MJ, Godley BJ (2009). Insights into habitat utilization by Green Turtles (Chelonia Mydas) during the inter-nesting period animal-borne digital cameras.
Marine Technology Society Journal,
43(3), 51-59.
Abstract:
Insights into habitat utilization by Green Turtles (Chelonia Mydas) during the inter-nesting period animal-borne digital cameras
Many marine turtle habitat utilization studies have historically relied on inferences from logged data or direct visual observation. Here we remotely investigate aspects of the habitat utilization of inter-nesting female green turtles (Chelonia mydas) nesting on the Mediterranean island of Cyprus. Using an animal- borne digital video camera set to take only still images, with an integrated time-depth recorder, we recorded a total of 2, 375 images and 2, 899 dives for two nesting female green turtles. Both turtles spent over 80% of their time at depths of 5 m or less. Photographic evidence allowed us to categorize subsurface behaviors from 66 of the deeper dives (turtle a with 40 dives and turtle B with 26 dives) containing more than 900 images into three categories: swimming, probable foraging and resting. Methodologically, our study highlights future utility in using camera technologies to clarify at-sea behavior of marineorganisms, with a view to generating reliable time budgets.
Abstract.
Inger R, Attrill MJ, Bearhop S, Broderick AC, Grecian WJ, Hodgson DJ, Sheehan E, Votier SC, Witt MJ, Godley BJ, et al (2009). Marine Renewable Energy: potential benefits to biodiversity? an urgent call for research.
Journal of Applied Ecology,
46, 1145-1153.
Abstract:
Marine Renewable Energy: potential benefits to biodiversity? an urgent call for research.
1. The evidence for anthropogenically induced climate change is overwhelming with the production of greenhouse gases from burning fossil fuels being a key driver. In response, many governments have initiated programmes of energy production from renewable sources.
2. The marine environment presents a relatively untapped energy source and offshore installations are likely to produce a significant proportion of future energy production. Wind power is the most advanced, with development of wave and tidal energy conversion devices expected to increase worldwide in the near future.
3. Concerns over the potential impacts on biodiversity of marine renewable energy installations (MREI) include: habitat loss, collision risks, noise and electromagnetic fields. These factors have been posited as having potentially important negative environmental impacts.
4. Conversely, we suggest that if appropriately managed and designed, MREI may increase local biodiversity and potentially benefit the wider marine environment. Installations have the capacity to act as both artificial reefs and fish aggregation devices, which have been used previously to facilitate restoration of damaged ecosystems, and de facto marine-protected areas, which have proven successful in enhancing both biodiversity and fisheries.
5. The deployment of MREI has the potential to cause conflict among interest groups including energy companies, the fishing sector and environmental groups. Conflicts should be minimized by integrating key stakeholders into the design, siting, construction and operational phases of the installations, and by providing clear evidence of their potential environmental benefits.
6. Synthesis and applications. MREI have the potential to be both detrimental and beneficial to the environment but the evidence base remains limited. To allow for full biodiversity impacts to be assessed, there exists an urgent need for additional multi and inter-disciplinary research in this area ranging from engineering to policy. Whilst there are a number of factors to be considered, one of the key decisions facing current policy makers is where installations should be sited, and, dependent upon site, whether they should be designed to either minimize negative environmental impacts or as facilitators of ecosystem restoration.
Abstract.
Author URL.
Greaves D, Smith G, Attrill M, Belmont M, Chadwick A, Conley D, Eccleston A, Godley B, Harrington N, Hor CL, et al (2009). Marine renewable energy development - research, design, install.
PROCEEDINGS OF THE INSTITUTION OF CIVIL ENGINEERS-MARITIME ENGINEERING,
162(4), 187-196.
Author URL.
Inger R, Attrill MJ, Bearhop S, Broderick AC, James Grecian W, Hodgson DJ, Mills C, Sheehan E, Votier SC, Witt MJ, et al (2009). Marine renewable energy: Potential benefits to biodiversity? an urgent call for research.
Journal of Applied Ecology,
46(6), 1145-1153.
Abstract:
Marine renewable energy: Potential benefits to biodiversity? an urgent call for research
The evidence for anthropogenically induced climate change is overwhelming with the production of greenhouse gases from burning fossil fuels being a key driver. In response, many governments have initiated programmes of energy production from renewable sources. 2. The marine environment presents a relatively untapped energy source and offshore installations are likely to produce a significant proportion of future energy production. Wind power is the most advanced, with development of wave and tidal energy conversion devices expected to increase worldwide in the near future. 3. Concerns over the potential impacts on biodiversity of marine renewable energy installations (MREI) include: habitat loss, collision risks, noise and electromagnetic fields. These factors have been posited as having potentially important negative environmental impacts. 4. Conversely, we suggest that if appropriately managed and designed, MREI may increase local biodiversity and potentially benefit the wider marine environment. Installations have the capacity to act as both artificial reefs and fish aggregation devices, which have been used previously to facilitate restoration of damaged ecosystems, and de facto marine-protected areas, which have proven successful in enhancing both biodiversity and fisheries. 5. The deployment of MREI has the potential to cause conflict among interest groups including energy companies, the fishing sector and environmental groups. Conflicts should be minimized by integrating key stakeholders into the design, siting, construction and operational phases of the installations, and by providing clear evidence of their potential environmental benefits. 6. Synthesis and applications. MREI have the potential to be both detrimental and beneficial to the environment but the evidence base remains limited. To allow for full biodiversity impacts to be assessed, there exists an urgent need for additional multi and inter-disciplinary research in this area ranging from engineering to policy. Whilst there are a number of factors to be considered, one of the key decisions facing current policy makers is where installations should be sited, and, dependent upon site, whether they should be designed to either minimize negative environmental impacts or as facilitators of ecosystem restoration. © 2009 British Ecological Society.
Abstract.
Richardson PB, Bruford MW, Calosso MC, Campbell LM, Clerveaux W, Formia A, Godley BJ, Henderson AC, McClellan K, Newman S, et al (2009). Marine turtles in the Turks and Caicos Islands: Remnant rookeries, regionally significant foraging stocks, and a major turtle fishery.
Chelonian Conservation and Biology,
8(2), 192-204.
Abstract:
Marine turtles in the Turks and Caicos Islands: Remnant rookeries, regionally significant foraging stocks, and a major turtle fishery
This study reviews the status of marine turtles in the Turks and Caicos Islands (TCI) using data gathered during a multidisciplinary study involving field surveys, questionnaire-based interviews, and molecular genetics between 2002 and 2006. Large aggregations of foraging turtles in the archipelago's waters are dominated by juvenile green (Chelonia mydas) and hawksbill turtles (Eretmochelys imbricata), with provisional mixed-stock analysis of these species suggesting that the aggregations originate predominantly from larger and relatively proximate source rookeries in the Wider Caribbean region. This study also suggests that the islands host remnant nesting populations of turtles, with hawksbill turtle nests recorded more frequently than green and loggerhead turtle (Caretta caretta) nests. The TCI islanders retain a culture of turtle use, with the current regulated and legitimate harvest likely to be one of the largest among the Caribbean Islands. This study suggests that historic and current harvest of turtles and their eggs in the TCI may have contributed to the apparent decline in the country's nesting populations. In order to address this conservation concern, changes to the regulation and management of the TCI's turtle fishery are necessary, but further research is needed to inform these changes. © 2009 Chelonian Research Foundation.
Abstract.
Hartnoll RG, Broderick AC, Godley BJ, Saunders KE (2009). POPULATION STRUCTURE OF THE LAND CRAB JOHNGARTHIA LAGOSTOMA ON ASCENSION ISLAND (VOL 29, PG 57, 2009).
JOURNAL OF CRUSTACEAN BIOLOGY,
29(2), 281-281.
Author URL.
Hartnoll RG, Broderick AC, Godley BJ, Saunders KE (2009). Population structure of the land crab Johngarthia lagostoma on ascension Island.
Journal of Crustacean Biology,
29(1), 57-61.
Abstract:
Population structure of the land crab Johngarthia lagostoma on ascension Island
The population structure of the land crab Johngarthia lagostoma was studied on Ascension Island from 2005-2007, predominantly during the period of the seaward breeding migrations; approximately 4000 crabs were examined. Sex ratio varied according to location of sampling. Males predominated in permanent residential areas on high ground. Sexes were equal along migration routes to the sea. Females predominated in the breeding sites on the shore. Very few immature crabs (< 60 mm CW) were found. Males had modal and maximum sizes of 100-109 mm and 120 mm CW, females of 90-99 mm and 110 mm, respectively. An aging population is indicated. Crabs < 40 mm CW were all dark coloured, and colour variation into yellow, purple and intermediate morphs developed between 40-50 mm CW.Overall colour distribution of the population was 85% yellow, 5% intermediate, and 10% purple. Yellow morphs were more abundant in females (89%) than males (81%). The predominance of yellow morphs may be an adaptation to reduce heat stress.
Abstract.
Hawkes LA, Broderick AC, Godfrey MH, Godley BJ (2009). REVIEW: Climate change and marine turtles.
,
7, 137-154.
Abstract:
REVIEW: Climate change and marine turtles
ABSTRACT: Marine turtles occupy a wide range of terrestrial and marine habitats, and many aspects
of their life history have been demonstrated to be closely tied to climatic variables such as ambient
temperature and storminess. As a group, therefore, marine turtles may be good indicators of climate
change effects on coastal and marine habitats. Despite the small number of species in the taxon and
a growing body of research in the field, the evidence base to predict resultant impacts of climate
change remains relatively poor. We review the data from peer-reviewed publications to assess the
likely impacts of climate change on marine turtles and highlight the types of data that would be most
useful for an accurate assessment of future effects. The cumulative indications from these previous
studies indicate that future research should focus on: (1) climate change effects on key habitats upon
which turtles depend; (2) factors that influence nest site selection; (3) the consequences of skewed
primary sex ratios; and (4) the effect of climate change on turtles at sea, for example range shifts and
dietary breadth. Although it is too early to give detailed management recommendations, careful
protection of coastlines along which turtles nest should be considered, as should the protection of
beaches that produce male hatchlings, which may be of increased importance in the future. More
active management approaches, for example translocation of eggs to suitable yet vacant nesting
beaches, may be necessary to consider under worst-case scenarios.
Abstract.
Godfrey M, Godley B, Mrosovsky N, Seminoff J, Shanker K, Webb G (2009). Save the Red List. New Scientist, 202(2707).
Robinson RA, Crick HQP, Learmonth JA, Maclean IMD, Thomas CD, Bairlein F, Forchhammer MC, Francis CM, Gill JA, Godley BJ, et al (2009). Travelling through a warming world - climate change and migratory species. Endangered Species Research, 7, 87-99.
Blumenthal JM, Abreu-Grobois FA, Austin TJ, Broderick AC, Bruford MW, Coyne MS, Ebanks-Petrie G, Formia A, Meylan PA, Meylan AB, et al (2009). Turtle groups or turtle soup: dispersal patterns of hawksbill turtles in the Caribbean.
Mol Ecol,
18(23), 4841-4853.
Abstract:
Turtle groups or turtle soup: dispersal patterns of hawksbill turtles in the Caribbean.
Despite intense interest in conservation of marine turtles, spatial ecology during the oceanic juvenile phase remains relatively unknown. Here, we used mixed stock analysis and examination of oceanic drift to elucidate movements of hawksbill turtles (Eretmochelys imbricata) and address management implications within the Caribbean. Among samples collected from 92 neritic juvenile hawksbills in the Cayman Islands we detected 11 mtDNA control region haplotypes. To estimate contributions to the aggregation, we performed 'many-to-many' mixed stock analysis, incorporating published hawksbill genetic and population data. The Cayman Islands aggregation represents a diverse mixed stock: potentially contributing source rookeries spanned the Caribbean basin, delineating a scale of recruitment of 200-2500 km. As hawksbills undergo an extended phase of oceanic dispersal, ocean currents may drive patterns of genetic diversity observed on foraging aggregations. Therefore, using high-resolution Aviso ocean current data, we modelled movement of particles representing passively drifting oceanic juvenile hawksbills. Putative distribution patterns varied markedly by origin: particles from many rookeries were broadly distributed across the region, while others would appear to become entrained in local gyres. Overall, we detected a significant correlation between genetic profiles of foraging aggregations and patterns of particle distribution produced by a hatchling drift model (Mantel test, r = 0.77, P < 0.001; linear regression, r = 0.83, P < 0.001). Our results indicate that although there is a high degree of mixing across the Caribbean (a 'turtle soup'), current patterns play a substantial role in determining genetic structure of foraging aggregations (forming turtle groups). Thus, for marine turtles and other widely distributed marine species, integration of genetic and oceanographic data may enhance understanding of population connectivity and management requirements.
Abstract.
Author URL.
Aiken JJ, Godley BJ, Broderick AC, Austin T, Ebanks-Petrie G, Hays GC (2009). Two hundred years after a commercial marine turtle fishery: the current status of marine turtles nesting in the Cayman Islands. Oryx, 35(02), 145-145.
Godfrey MH, Godley BJ (2008). AS WE SEE IT: Seeing past the red: flawed IUCN global listings for sea turtles. Endangered Species Research, 6, 155-159.
Tomás J, Gozalbes P, Raga JA, Godley BJ (2008). Bycatch of loggerhead sea turtles: Insights from 14 years of stranding data.
Endangered Species Research,
5(2-3), 161-169.
Abstract:
Bycatch of loggerhead sea turtles: Insights from 14 years of stranding data
We present a detailed analysis of sea turtle strandings (n = 619) over a 14 yr period (1993 to 2006) from the Valencian Community (eastern Spain). Loggerhead turtles Caretta caretta accounted for 98.1 % of recorded strandings. Although we detected an increasing trend in the annual number of strandings over the study period, we expect that this Was driven primarily by the increase in detection effort. Loggerhead turtles were mainly juveniles (mean ± SD curved carapace length from notch to tip [CCL] = 53.6 ± 12.6; range: 16 to 80.2 cm, n = 312) and strandings were far more frequent in summer months (69.6 % June to September). We believe that interaction with longline fisheries was by far the main cause of observed stranding (> 28 % of all cases, 43.5 % of 393 turtles with likely mortality cause identified). Turtles showing signs of interaction with longlines were, on average, larger (CCL = 57.5 ± 10.4; range: 29.8 to 80.2 cm, n = 116) than turtles stranded due to other causes (CCL = 51.4 ± 13.3; range: 16 to 79 cm, n = 196; t-test: t = -4.49, p < 0.001) and were more frequent in summer months, when longline fishing effort off the coast was highest. Recent reductions in longline effort may have led to a decrease in recent years in the proportion of stranded turtles with evidence of longline interaction. Although inferences from stranding data must be subject to a number of caveats, when considered over wide spatio-temporal extents and in conjunction with other data sources, they can offer useful insights into the geographic ranges, seasonal distribution and life history of marine species of conservation concern. © Inter-Research 2008.
Abstract.
Broderick, A.C. Frett, G. Gore, S. (2008). Down But Not Out: Marine Turtles of the British Virgin Islands. Animal Conservation
Patino-Martinez J, Marco A, Quinones L, Godley B (2008). Globally significant nesting of the leatherback turtle (Dermochelys coriacea) on the Caribbean coast of Colombia and Panama.
BIOLOGICAL CONSERVATION,
141(8), 1982-1988.
Author URL.
Jackson AL, Broderick AC, Fuller WJ, Glen F, Ruxton GD, Godley BJ (2008). Sampling design and its effect on population monitoring: How much monitoring do turtles really need?.
Biological ConservationAbstract:
Sampling design and its effect on population monitoring: How much monitoring do turtles really need?
Marine turtles are a taxon of world-wide conservation concern. Effective long-term monitoring is hampered by the fact that populations are widely dispersed except during the breeding season. Thus most monitoring programmes focus on nesting beaches, necessitating resource intensive studies, often over months, that could conceivably, be less comprehensive and focus on more parsimonious sampling. We analyse 11 years of exhaustive monitoring data for two species of Mediterranean marine turtles (Chelonia mydas and Caretta caretta). We resample using a variety of plausible sub-sampling regimens to estimate the total annual nesting population. We project our dataset into the future applying a range of population change rates to explore how adopting a monitoring programme based on sub-sampling would, for example, affect our ability to detect population decline. We show that accurate annual population estimates can be achieved with as few as 14 days of survey effort providing monitoring spans the peak of nesting. Furthermore, the modelled impact of sampling-based monitoring suggests that the duration to detect population change is not increased greatly. Our findings have implications for all marine turtle monitoring and have applicability to other animal groups. It is often considered desirable to perform exhaustive monitoring, with aversion of basing policy recommendations on partial data. However, comprehensive long-term monitoring programmes, particularly in developing nations, although presenting a number of advantages, are often impossible. Accurate total annual censuses can be achieved through a variety of sub-sampling regimens without sacrificing the ability to detect changes in the population trends over time. In this example, a solid block of at least 3 weeks sampling that encompasses the peak of the nesting season is advised. © 2008 Elsevier Ltd. All rights reserved.
Abstract.
Jackson AL, Broderick AC, Fuller WJ, Glen F, Ruxton GD, Godley BJ (2008). Sampling design and its effect on population monitoring: How much monitoring do turtles really need?.
BIOLOGICAL CONSERVATION,
141(12), 2932-2941.
Author URL.
Broderick, A.C. Coyne, M.S. Formia, A. (2008). Satellite tracking highlights difficulties in the design of effective protected areas for leatherback turtles during the internesting period. Oryx
Rees AF, Jony M, Margaritoulis D, Godley BJ (2008). Satellite tracking of a green turtle, chelonia mydas, from syria further highlights importance of north africa for mediterranean turtles.
Zoology in the Middle East,
45(1), 49-54.
Abstract:
Satellite tracking of a green turtle, chelonia mydas, from syria further highlights importance of north africa for mediterranean turtles
In 2006, we tracked a single Green Turtle after nesting Latakia, providing the first evidence of foraging grounds and migratory routes from this rookery which is one of the most important nesting areas in the Mediterranean. Tracking lasted 95 days during which time the turtle migrated southward (minimum average speed=0.9 km/h) and then westward (minimum average speed=1.6 km/h), following the coast. The turtle settled in the Bay of As Sallum, western Egypt where it remained in neritic, coastal waters for the final 26 days of transmissions. These results, when combined with findings from Cyprus, Turkey and Greece, further highlight the importance of the North African coast for foraging adult turtles and the need for effective conservation measures to be adopted there. © 2008 Taylor & Francis Group, LLC.
Abstract.
Godley BJ, Blumenthal JM, Broderick AC, Coyne MS, Godfrey MH, Hawkes LA, Witt MJ (2008). Satellite tracking of sea turtles: Where have we been and where do we go next?.
Endangered Species Research,
4, 3-22.
Author URL.
Mcgowan A, Broderick AC, Godley BJ (2008). Seabird populations of the Chagos Archipelago, Indian Ocean: an evaluation of IBA sites.
ORYX,
42(3), 424-429.
Author URL.
Godfrey MH, Godley BJ (2008). Seeing past the red: Flawed IUCN global listings for sea turtles.
Endangered Species Research,
6(2), 155-159.
Abstract:
Seeing past the red: Flawed IUCN global listings for sea turtles
The Red List of Threatened Species, produced by the International Union for the Conservation of Nature and Natural Resources/World Conservation Union (IUCN) classifies the global populations of all 7 sea turtle species, except the flatback Natator depressus, as Endangered or Critically Endangered. However, the IUCN Marine Turtle Specialist Group (MTSG), which carries out the assessments for the IUCN, is experiencing internal debate over the relevance and usefulness of such statements. Assigning a distinct Red List category to the global population, as a single management unit, does not capture the reality of regional and local populations that tend to have different (positive or negative) trajectories. From a technical viewpoint, setting the time scale for assessment at 3 generations, which is 60 to 100+ yr for sea turtles, means few reference points are available for quantifying past changes in abundance. Moreover, it hardly establishes a sense of urgency for action to prevent future changes over long time scales. The application of current Red List criteria, resulting in flawed categorizations, creates problems of credibility. When a species that may number in the millions in an ocean basin is classified as being at the same 'very high risk of extinction in the wild,' as a species represented by just a few individuals, there is something fundamentally wrong with the assessment system. We suggest that MTSG members desist from using the current Red List criteria to generate implausible global assessments of extinction risk and instead concentrate their efforts on developing more realistic and credible criteria, perhaps for application at the regional level. © Inter-Research 2008.
Abstract.
Leeney RH, Amies R, Broderick AC, Witt MJ, Loveridge J, Doyle J, Godley BJ (2008). Spatio-temporal analysis of cetacean strandings and bycatch in a UK fisheries hotspot.
BIODIVERSITY AND CONSERVATION,
17(10), 2323-2338.
Author URL.
Godfrey MH, Roberts DL, Godley BJ (2008). Taking it as red: an introduction to the Theme Section on the IUCN Red List of Threatened Species.
Endangered Species Research,
6(2), 109-111.
Abstract:
Taking it as red: an introduction to the Theme Section on the IUCN Red List of Threatened Species
The IUCN Red List of Threatened Species (www.redlist.org) is a comprehensive list of relative extinction risk for species throughout the world, and it is commonly referenced in the scientific literature. Established in 1963, the IUCN Red List and its Criteria have been revised regularly to make them more scientific and objective. Nevertheless, the aim of the IUCN Red List to establish global standards across varied taxa has generated some controversy, particularly in terms of what is the most appropriate scale for both assessing the threat of extinction and setting conservation priorities for particular species. The papers included in this Theme Section of Endangered Species Research focus on the IUCN Red List and provide several recommendations for strengthening this conservation tool. © Inter-Research 2008.
Abstract.
Godley BJ, Wilson RP (2008). Tracking vertebrates for consevation: Introduction.
Endangered Species Research,
4, 1-2.
Author URL.
Robinson RA, Crick HQP, Learmonth JA, Maclean IMD, Thomas CD, Bairlein F, Forchhammer MC, Francis CM, Gill JA, Godley BJ, et al (2008). Travelling through a warming world: climate change and migratory species.
Endangered Species Research,
7(2), 87-99.
Abstract:
Travelling through a warming world: climate change and migratory species
Long-distance migrations are among the wonders of the natural world, but this multitaxon review shows that the characteristics of species that undertake such movements appear to make them particularly vulnerable to detrimental impacts of climate change. Migrants are key components of biological systems in high latitude regions, where the speed and magnitude of climate change impacts are greatest. They also rely on highly productive seasonal habitats, including wetlands and ocean upwellings that, with climate change, may become less food-rich and predictable in space and time. While migrants are adapted to adjust their behaviour with annual changes in the weather, the decoupling of climatic variables between geographically separate breeding and nonbreeding grounds is beginning to result in mistimed migration. Furthermore, human land-use and activity patterns will constrain the ability of many species to modify their migratory routes and may increase the stress induced by climate change. Adapting conservation strategies for migrants in the light of climate change will require substantial shifts in site designation policies, flexibility of management strategies and the integration of forward planning for both people and wildlife. While adaptation to changes may be feasible for some terrestrial systems, wildlife in the marine ecosystem may be more dependent on the degree of climate change mitigation that is achievable
Abstract.
Fuller WJ, Broderick AC, Phillips RA, Silk JRD, Godley BJ (2008). Utility of geolocating light loggers for indicating at-sea movements in sea turtles.
Endangered Species Research,
4, 139-146.
Author URL.
Fuller WJ, Broderick AC, Phillips RA, Silk JRD, Godley BJ (2008). Utility of geolocating light loggers for indicating at-sea movements in sea turtles. Endangered Species Research, 4, 139-146.
McGowan A, Woodfield NK, Hilton G, Broderick AC, Godley BJ (2007). A rigorous assessment of the Avifauna of a small Caribbean Island: a case study in Anegada, British Virgin Islands.
Caribbean Journal of Science,
43(1), 99-116.
Abstract:
A rigorous assessment of the Avifauna of a small Caribbean Island: a case study in Anegada, British Virgin Islands
The avifauna of the British Virgin Islands (BVI) has received little attention from researchers. The lack of baseline information is therefore a major hindrance to the construction of management plans. Here we present detailed monitoring data on the species composition and numbers of each-species for the island of Anegada, BVI. We surveyed the birds of Anegada between November 2003 and March 2005 utilising a combination of coastal transects, wetland bird counts, point counts, and species-specific survey methods for nocturnal species. A total of 99 different species were recorded, with a large increase in the number of species and number of individuals centred around peak migration in September. Although there is a depauperate terrestrial bird community consisting of predominately generalist species, it holds important populations of regional avifauna. For example, it hosts five regionally important breeding seabird colonies and its wetlands provide an important stop-over and over-wintering site for many species of shorebirds and waterbirds. In addition, the Eastern salt ponds are also the only breeding site for the greater flamingo, Phoenicopterus ruber, within the territory. We discuss our findings within the current framework of regional conservation and provide recommendations for the implementation of a territory wide monitoring program as a first step towards meeting the UK's commitments under several multilateral environmental agreements. Copyright 2007 College of Arts and Science.
Abstract.
Godley, B.J. (2007). A step towards seascape scale conservation: using VMS to map fishing activity.
PLoS ONE Author URL.
Witt MJ, Godley BJ (2007). A step towards seascape scale conservation: using vessel monitoring systems (VMS) to map fishing activity.
PLoS One,
2(10).
Abstract:
A step towards seascape scale conservation: using vessel monitoring systems (VMS) to map fishing activity.
BACKGROUND: Conservation of marine ecosystems will require a holistic understanding of fisheries with concurrent spatial patterns of biodiversity. METHODOLOGY/PRINCIPAL FINDINGS: Using data from the UK Government Vessel Monitoring System (VMS) deployed on UK-registered large fishing vessels we investigate patterns of fisheries activity on annual and seasonal scales. Analysis of VMS data shows that regions of the UK European continental shelf (i.e. Western Channel and Celtic Sea, Northern North Sea and the Goban Spur) receive consistently greater fisheries pressure than the rest of the UK continental shelf fishing zone. CONCLUSIONS/SIGNIFICANCE: VMS provides a unique and independent method from which to derive patterns of spatially and temporally explicit fisheries activity. Such information may feed into ecosystem management plans seeking to achieve sustainable fisheries while minimising putative risk to non-target species (e.g. cetaceans, seabirds and elasmobranchs) and habitats of conservation concern. With multilateral collaboration VMS technologies may offer an important solution to quantifying and managing ecosystem disturbance, particularly on the high-seas.
Abstract.
Author URL.
Woodfield, N.K. Hilton, G. Broderick, A.C. (2007). An assessment of the avifauna of a small remote island: a case study of Anegada, British Virgin Islands. Caribbean Journal of Science
Broderick AC, Coyne MS, Fuller WJ, Glen F, Godley BJ (2007). Correction for Broderick. <i>et al.</i>. Fidelity and over-wintering of sea turtles.
Proceedings of the Royal Society B: Biological Sciences,
274(1629), 3183-3183.
Abstract:
Correction for Broderick. et al.. Fidelity and over-wintering of sea turtles
. Correction for ‘Fidelity and over-wintering of sea turtles’ by Annette C. Broderick, Michael S. Coyne, Wayne J. Fuller, Fiona Glen and Brendan J. Godley (Proc. R. Soc. B
. 274
. 1533–1538.
(doi:
. 10.1098/rspb.2007.0211
. )).
.
. The scale bar in figure 2b was incorrect, and should read as follows: 5 km.
Abstract.
Berrow, S. McGrath, D. O’Brien, J. (2007). Effects of pingers on the behaviour of bottlenose dolphins. Journal of the Marine Biological Association of the United Kingdom, 87, 129-133.
Broderick AC, Coyne MS, Fuller WJ, Glen F (2007). Fidelity and over-wintering of sea turtles. Proceedings of the Royal Society B Biological Sciences, 274(1617), 1533-1538.
Formia A, Broderick AC, Glen F, Godley BJ, Hays GC, Bruford MW (2007). Genetic composition of the Ascension Island green turtle rookery based on mitochondrial DNA: implications for sampling and diversity.
Endangered Species Research,
3, 145-158.
Author URL.
HAWKES LA, BRODERICK AC, GODFREY MH, GODLEY BJ (2007). Investigating the potential impacts of climate change on a marine turtle population. Global Change Biology, 0(0), 070621084512044-???.
Hawkes LA, Broderick AC, Godfrey MH, Godley BJ (2007). Investigating the potential impacts of climate change on marine turtles. Global Change Biology, 13(5), 923-932.
Solomon, J.L. Blumenthal, J.M. Austin, T.J. (2007). Monitoring and conservation of critically reduced marine turtle nesting populations: lessons from the Cayman Islands. Animal Conservation, 10, 39-47.
Hawkes LA, Broderick AC, Godfrey MS, Coyne MS, Godley BJ (2007). Only some like it hot: quantifying the environmental niche of loggerhead sea turtles. Diversity and Distributions, 13(4), 447-457.
Witt MJ, Broderick AC, Johns DJ, Martin C, Penrose R, Hoogmoed MS, Godley BJ (2007). Prey landscapes help identify potential foraging habitats for leatherback turtles in the NE Atlantic.
Marine Ecology Progress Series,
337, 231-243.
Abstract:
Prey landscapes help identify potential foraging habitats for leatherback turtles in the NE Atlantic
Identifying key marine megavertebrate habitats has become ever more important as concern increases regarding global fisheries bycatch and accelerated climate change. This will be aided by a greater understanding of the patterns and processes determining the spatiotemporal distribution of species of conservation concern. We identify probable foraging grounds for leatherback turtles in the NE Atlantic using monthly landscapes of gelatinous organism distribution constructed from Continuous Plankton Recorder Survey data. Using sightings data (n = 2013 records, 1954 to 2003) from 9 countries (UK, Ireland, France, Belgium, the Netherlands, Denmark, Germany, Norway and Sweden), we show sea surface temperatures of approximately 10 to 12°C most likely indicate the lower thermal threshold for accessible habitats during seasonal foraging migrations to high latitudes. Integrating maps of gelatinous plankton as a possible indicator of prey distribution with thermal tolerance parameters demonstrates the dynamic (spatial and temporal) nature of NE Atlantic foraging habitats. We highlight the importance of body size-related thermal constraints in structuring leatherback foraging populations and demonstrate a latitudinal gradient in body size (Bergmann's rule) where smaller animals are excluded from higher latitude foraging areas. We highlight the marine area of the European continental shelf edge as being both thermally accessible and prey rich, and therefore potentially supporting appreciable densities of foraging leatherbacks, with some suitable areas not yet extensively surveyed. © Inter-Research 2007.
Abstract.
Broderick, A.C. Johns, D.J. Martin, C.S. (2007). Prey landscapes help identify potential foraging habitats for leatherback turtles in the northeast Atlantic. Marine Ecology Progress Series, 337, 231-244.
Witt MJ, Penrose R, Godley BJ (2007). Spatio-temporal patterns of juvenile marine turtle occurrence in waters of the European continental shelf.
Marine Biology,
151(3), 873-885.
Abstract:
Spatio-temporal patterns of juvenile marine turtle occurrence in waters of the European continental shelf
We present data spanning approximately 100 years regarding the spatial and temporal occurrence of marine turtle sightings and strandings in the northeast Atlantic from two public recording schemes and demonstrate potential signals of changing population status. Records of loggerhead (n = 317) and Kemp's ridley (n = 44) turtles occurring on the European continental shelf were most prevalent during the autumn and winter, when waters were coolest. In contrast, endothermic leatherback turtles (n = 1,668) were most common during the summer. Analysis of the spatial distribution of hard-shell marine turtle sightings and strandings highlights a pattern of decreasing records with increasing latitude. The spatial distribution of sighting and stranding records indicates that arrival in waters of the European continental shelf is most likely driven by North Atlantic current systems. Future patterns of spatial-temporal distribution, gathered from the periphery of juvenile marine turtles habitat range, may allow for a broader assessment of the future impacts of global climate change on species range and population size. © 2006 Springer-Verlag.
Abstract.
Penrose, R. Godley, B.J. (2007). Spatio-temporal patterns of juvenile marine turtle occurrence in waters of the European continental shelf. Marine Biology, 151, 873-885.
Broderick AC, Frauenstein R, George T, Glen F (2006). Are green turtles globally endangered?. Global Ecology and Biogeography, 15(1), 21-26.
McGowan A, Broderick A, Gore S, Hilton G, Woodfield N, Godley B (2006). Breeding seabirds in the British Virgin Islands. Endangered Species Research, 2, 15-20.
Broderick, A.C. Gore, S. Hilton, G. (2006). Breeding seabirds in the British Virgin Islands.
Endangered Species Research,
3, 1-6.
Author URL.
Godley B (2006). Editorial: Endangered Species Research—a journal on the move!. Endangered Species Research, 2, i-ii.
Broderick, A.C. Campbell, L.M. Godley, B.J. (2006). Marine turtle fisheries in the UK Overseas Territories of the Caribbean: domestic legislation and the requirements of multilateral agreements. Journal of International Wildlife Law and Policy, 9, 223-246.
Godley, B.J. Dontaine, M.W. Bruford (2006). Mitochondrial DNA diversity and phylogeography of endangered green turtle (Chelonia mydas) populations in Africa. Conservation Genetics, 7, 353-369.
Abreu-Grobois, A. Muhlia-Melo, A.. Bell, C. (2006). Movement Patterns of Green Turtles (Chelonia mydas) in Cuba Adjacent Caribbean Waters Inferred from Flipper Tag Recaptures. Journal of Herpetology, 40, 22-34.
Hawkes LA, Broderick AC, Coyne MS, Godfrey MH, Lopez-Jurado LF, Lopez-Suarez P, Merino SE, Varo-Cruz N, Godley BJ (2006). Phenotypically linked dichotomy in sea turtle foraging strategies requires multiple conservation approaches. Current Biology, 16(10), 990-995.
Broderick, A.C. Godley, B.J. Hays, G.C. (2006). Rhythmic Throat Oscillations in Nesting Green Turtles (Chelonia mydas). Chelonian Conservation and Biology, 5, 299-301.
Solomon, J.L. Bell, C.D. Austin, T.J. (2006). Satellite tracking highlights the need for international cooperation in marine turtle management.
Endangered Species Research,
2, 51-61.
Author URL.
Broderick, A.C. Godley, B.J. Hays, G.C. (2006). Thermal control of hatchling emergence patterns in marine turtles. Journal of Experimental Marine Biology and Ecology, 334, 31-42.
Godley B, Coyne M (2006). Tracking all over the world.
Planet Earth(SPRING).
Abstract:
Tracking all over the world
Fitting marine animals that migrate through different international maritime jurisdictions with satellite transmitters and following them from space can enable the retrieval of the data about their environments from anywhere in the world via Internet. A new web-based Satellite Tracking and Analysis Tool (STAT) helps biologists to track animals by automating the work with satellite-tracking data, including downloading of the data daily, updating maps, and creating backups. It also links in information on water depths, sea surface temperatures, ocean currents, and chlorophyll concentrations, helping animal-biologists to understand the behavior and needs of elusive marine animals. It also makes available a database of locations that is automatically available to all of them.
Abstract.
Blumenthal, J.M. Austin, T.J. Solomon, J.L. (2006). Traditional Caymanian fishery may impede local marine turtle population recovery.
Endangered Species Research,
2, 63-69.
Author URL.
Broderick, A.C. Godley, B.J. Hays, G.C. (2005). Patterns in the emergence of. green (Chelonia mydas) and loggerhead (Caretta caretta) turtle hatchlings from their nests. Marine Biology, 146, 1039-1049.
Godley, B.J. (2005). Satellite Tracking and Analysis Tool (STAT): an Integrated System for Archiving, Analyzing and Mapping Animal Tracking Data.
Marine Ecology Progress Series,
301(1), 1-7.
Author URL.
Parsons, J. Austin, T.J. Broderick, A.C. (2005). Some of them came home: the Cayman Turtle Farm headstarting project for the green turtle Chelonia mydas. Oryx, 39, 137-148.
Hawkes LA, Broderick, A.C. Godfrey, M.H. Godley, B.J. (2005). Status of nesting loggerhead turtles Caretta caretta at Bald Head Island (North Carolina, USA) after 24 years of intensive monitoring and conservation. Oryx, 39, 65-72.
Jeffers, J. Godley, B.J. (2005). The Status of Marine Turtles in Montserrat (Eastern Caribbean). Animal and Biodiversity Conservation, 28, 159-168.
Kelly A, Godley BJ, Furness RW (2004). Magpies, pica pica, at the southern limit of their range actively select their thermal environment at high ambient temperatures.
Zoology in the Middle East,
32(1), 13-26.
Abstract:
Magpies, pica pica, at the southern limit of their range actively select their thermal environment at high ambient temperatures
The effect of high ambient temperatures on the behaviour of Magpies (Pica pica) was assessed in northern Cyprus, which marks the southern limit of their European range. Magpies actively selected their thermal environment when temperatures rose above 31°C, by retreating to shaded areas. On days when the temperature was higher, Magpies appeared to spend more time perched in the shade and less time foraging. Flying and foraging activities were generally restricted to cooler parts of the day. Magpies were rarely seen panting or drinking and gular fluttering was not observed. We suggest that utilisation of shade is important for Magpies to regulate their body temperature, allowing them to remain common at the southern limit of their range despite experiencing high temperatures. © 2004 Taylor & Francis Group, LLC.
Abstract.
Hays GC, Broderick AC, Godley BJ, Luschi P, Nichols WJ, Chaloupka M, Parker D, Balazs G (2004). Tracking turtles to their death. Marine Ecology Progress Series, 283, 299-302.
Broderick, A.C. Glen, F. Godley, B.J. (2003). Climate change and sea turtles: a 150-year reconstruction of incubation temperatures at a major marine turtle rookery. Global Change Biology, 9, 642-646.
Broderick, A.C. Godley, B.J. Hays, G.C. (2003). Incubation environment affects phenotype of naturally incubated green turtle hatchlings. Journal of the Marine Biological Association of the United Kingdom, 83, 1183-1186.
Åkesson, S. Broderick, A.C. Glen, F. (2003). Island finding ability of marine turtles. Proceedings of the Royal Society B, 270, S5-S7.
Lima, E. HS, M. Åkesson, S. (2003). Movement patterns of green turtles in Brazilian coastal waters described by satellite tracking and flipper tagging. Marine Ecology Progress Series, 253:279-288
Lima, E. HS, M. Åkesson, S. (2003). Movement patterns of green turtles in Brazilian coastal waters described by satellite tracking and flipper tagging. Marine Ecology Progress Series, 253, 279-288.
Broderick, A.C. Glen, F. Godley, B.J. (2003). Multiple paternity assessed using microsatellite markers, in green turtles Chelonia mydas (Linnaeus, 1758) of Ascension Island, South Atlantic. Journal of Experimental Marine Biology and Ecology, 291, 149-160.
Broderick, A.C. Glen, F. Godley, B.J. (2003). Navigation by green turtles: which strategy do displaced adults use to find Ascension Island?. Oikos, 103, 363-372.
Broderick, A.C. Glen, F. Hays, G.C. (2003). Post-nesting movements and submergence patterns of loggerhead marine turtles in the Mediterranean assessed by satellite tracking. Journal of Experimental Marine Biology and Ecology, 287, 119-134.
Broderick, A.C. Godley, B.J. Luschi, P. (2003). Satellite telemetry suggests high levels of fishing-induced mortality in marine turtles. Marine Ecology Progress Series, 262, 305-309.
Glen, F. Godley, B.J. Hays, G.C. (2003). Variation in reproductive output of marine turtles. Journal of Experimental Marine Biology and Ecology, 288, 95-109.
Glen, F. Broderick, A.C. Godley, B.J. (2002). Behavioural plasticity in a large marine herbivore: contrasting patterns of depth utilisation between two green turtle (Chelonia mydas) populations. Marine Biology, 141, 985-990.
Broderick, A.C. Godley, B.J. Lovell, P. (2002). Bi-phasal long-distance migration in green turtles. Animal Behaviour, 64, 895-898.
Broderick, A.C. Godley, B.J. Hays, G.C. (2002). Diving behaviour during the internesting interval for loggerhead turtles (Caretta caretta) nesting in Cyprus. Marine Ecology Progress Series, 227, 63-70.
Glen, F. Godley, B.J. Hays, G.C. (2002). Estimating the number of Green and Loggerhead Turtles nesting annually in the Mediterranean. Oryx, 36: 227-236
Broderick AC, Glen F, Godley BJ, Hays GC (2002). Estimating the size of nesting populations of Green and Loggerhead turtles in the Mediterranean. Oryx, 36, 227-236.
Barbosa, C. Indjai, B. Almeida, A. (2002). First census of the green turtle at Poilao, Bijagos Archipelago, Guinea-Bissau: the most important nesting colony on the Atlantic coast of Africa. Oryx, 36, 400-403.
Godley BJ, Broderick AC, Coyne MS, Richardson S (2002). Long-term satellite telemetry of the movements and habitat utilisation by green turtles in the Mediterranean. Ecography, 25(3), 352-362.
Broderick, A.C. Frauenstein, R. (2002). Reproductive seasonality and sexual dimorphism in green turtles. Marine Ecology Progress Series, 226, 125-133.
Broderick, A.C. Glen, F. (2002). Temperature dependent sex determination of Ascension Island green turtles. Marine Ecology Progress Series, 226, 115-124.
Broderick, A.C. Godley, B.J. West, S.A. (2002). The effects of incubation environment, sex and pedigree on the hatchling phenotype in a natural population of loggerhead turtles. Evolutionary Ecology Research, 4, 737-748.
Broderick, A.C. Glen, F. Godley, B.J. (2002). Water temperature and internesting intervals for loggerhead (Caretta caretta) and green (Chelonia mydas) sea turtles. Journal of Thermal Biology, 27, 429-432.
Broderick, A.C. Glen, F. Godley, B.J. (2002). Weight change associated with long-term fasting in a marine reptile: the case of green turtles (Chelonia mydas) at Ascension Island. Canadian Journal of Zoology, 80, 1299-1302.
Broderick, A.C. Glen, F. Godley, B.J. (2002). Weight change associated with long-term fasting in a marine reptile: the case of green turtles (Chelonia mydas) at Ascension Island. Canadian Journal of Zoology 80: 1299-1302. Canadian Journal of Zoology, 80, 1299-1302.
Godley B (2001). Asian Turtle Trade: Proceedings of a workshop on Conservation and Trade of Freshwater Turtles and Tortoises in Asia (Phnom Penh, Cambodia, 1–4 December 1999). Oryx, 35(3), 269-269.
Broderick, A.C. Deeming, J. Godley, B.J. (2001). Dipteran infestation of loggerhead (Caretta caretta), and green (Chelonia mydas), sea turtle nests in northern Cyprus. Journal of natural History, 35, 573-581.
Broderick, A.C. Godley, B.J. Metcalfe, J.D. (2001). Dive angles for a green turtle (Chelonia mydas). Journal of Marine Biological Association(UK), 81, 683-686.
Godley BJ, Broderick AC, Mrosovsky N (2001). Estimating hatchling sex ratios of loggerhead turtles in Cyprus from incubation durations.
MARINE ECOLOGY PROGRESS SERIES,
210, 195-201.
Author URL.
Mickleburgh S, Godley B, Ghazanfar SA (2001). Loch Lomondside. Oryx, 35(3), 269-269.
Broderick AC, Godley BJ, Hays GC (2001). Metabolic heating and the prediction of sex ratios for green turtles (Chelonia mydas). Physiological and Biochemical Zoology, 74(2), 161-170.
McGowan A, Rowe, L.V. Broderick, A.C. Godley, B.J. (2001). Nest factors predisposing loggerhead sea turtle (Caretta caretta) clutches to infestation by dipteran larvae on northern Cyprus. Copeia, 2001(3), 808-812.
Godley BJ, Broderick AC, Hays GC (2001). Nesting of green turtles (Chelonia mydas) at Ascension Island, South Atlantic.
BIOLOGICAL CONSERVATION,
97(2), 151-158.
Author URL.
Godley, B.J. Broderick, A.C. (2001). Nesting of the Green Turtle, Chelonia mydas, in the Mediterranean: a review of status and conservation needs. Zoology in the Middle East, 24, 45-74.
Akesson S, Luschi P, Papi F, Broderick AC, Glen F, Godley BJ, Hays GC (2001). Oceanic long-distance navigation: Do experienced migrants use the Earth's magnetic field?.
JOURNAL OF NAVIGATION,
54(3), 419-427.
Author URL.
Åkesson S, Luschi P, Broderick AC, Glen F, Godley BJ, Papi F, Hays GC (2001). Oceanic long-distance navigation: Do experienced migrants use the earth's magnetic field?.
Journal of Navigation,
54(3), 419-427.
Abstract:
Oceanic long-distance navigation: Do experienced migrants use the earth's magnetic field?
Albatrosses and sea turtles are known to perform extremely long-distance journeys between disparate feeding areas and breeding sites located on small, isolated, oceanic islands or at specific coastal sites. These oceanic journeys, performed mainly over or through apparently featureless mediums, indicate impressive navigational abilities, and the sensory mechanisms used are still largely unknown. This research used three different approaches to investigate whether bi-coordinate navigation based on magnetic field gradients is likely to explain the navigational performance of wandering albatrosses in the South Atlantic and Indian Oceans and of green turtles breeding on Ascension Island in the South Atlantic Ocean. The possibility that magnetic field parameters can potentially be used in a bi-coordinate magnetic map by wandering albatrosses in their foraging area was investigated by analysing satellite telemetry data published in the literature. The possibilities for using bi-coordinate magnetic navigation varied widely between different areas of the Southern Oceans, indicating that a common mechanism, based on a bi-coordinate geomagnetic map alone, was unlikely for navigation in these areas. In the second approach, satellite telemetry was used to investigate whether Ascension Island green turtles use magnetic information for navigation during migration from their breeding island to foraging areas in Brazilian coastal waters. Disturbing magnets were applied to the heads and carapaces of the turtles, but these appeared to have little effect on their ability to navigate. The only possible effect observed was that some of the turtles with magnets attached were heading for foraging areas slightly south of the control turtles along the Brazilian coast. In the third approach, breeding female green turtles were deliberately displaced in the waters around Ascension Island to investigate which cues these turtles might use to locate and return to the island; the results suggested that cues transported by wind might be involved in the final stages of navigation.
Abstract.
Luschi, P. Papi, F. Hays, G. (2001). Oceanic long-distance navigation: do experienced migrants use the Earth's magnetic field?. Proceedings of the Royal Society of navigation, 27, 1-10.
Mickleburgh S, Godley B, Ghazanfar SA (2001). Publications. Oryx, 35(03).
Oerghi, A. Coyne, M.S. (2001). Resources available to individuals and organisations involved with marine turtle research and conservation in the Mediterranean. Zoology in the Middle East, 24, 55-60.
Godley BJ, Ouerghi A, Coyne MS (2001). Resources available to individuals and organisations involved with marine turtle research and conservation in the mediterranean.
Zoology in the Middle East,
24(1), 155-160.
Abstract:
Resources available to individuals and organisations involved with marine turtle research and conservation in the mediterranean
We review some key resources freely or cheaply available to those involved with marine turtle research and conservation in the Mediterranean. These include: Marine Turtle Newsletter, Listservs, bibliographic databases, Mediterranean specific technical manuals, IUCN Marine Turtle Specialist Group publications, internet sources and books. © 2001 Taylor & Francis Group, LLC.
Abstract.
Luschi P, Akesson S, Broderick AC, Glen F, Godley BJ, Papi F, Hays GC (2001). Testing the navigational abilities of ocean migrants: displacement experiments on green sea turtles (Chelonia mydas).
BEHAVIORAL ECOLOGY AND SOCIOBIOLOGY,
50(6), 528-534.
Author URL.
Hays GC, Akesson S, Broderick AC, Glen F, Godley BJ, Luschi P, Martin C, Metcalfe JD, Papi F (2001). The diving behaviour of green turtles undertaking oceanic migration to and from Ascension Island: dive durations, dive profiles and depth distribution.
JOURNAL OF EXPERIMENTAL BIOLOGY,
204(23), 4093-4098.
Author URL.
Åkesson, S. Godley, B.J. Luschi, P. (2001). The implications of location accuracy for the interpretation of satellite tracking data. Animal Behaviour, 61, 1035-1040.
Hays GC, Ashworth JS, Barnsley MJ, Broderick AC, Emery DR, Godley BJ, Henwood A, Jones EL (2001). The importance of sand albedo for the thermal conditions on sea turtle nesting beaches.
OIKOS,
93(1), 87-94.
Author URL.
Godley, B.J. Broderick, A.C. Glen, F. (2001). The movements and submergence behaviour of male green turtles at Ascension Island. Marine Biology, 139, 395-399.
Godley BJ, Broderick AC, Downie JR, Glen F, Houghton JDR, Kirkwood I, Reece S, Hays GC (2001). Thermal conditions in nests of loggerhead turtles: further evidence suggesting female skewed sex ratios of hatchling production in the Mediterranean.
JOURNAL OF EXPERIMENTAL MARINE BIOLOGY AND ECOLOGY,
263(1), 45-63.
Author URL.
Broderick AC, Godley BJ, Hays GC (2001). Trophic status drives interannual variability in nesting numbers of marine turtles.
Proc Biol Sci,
268(1475), 1481-1487.
Abstract:
Trophic status drives interannual variability in nesting numbers of marine turtles.
Large annual fluctuations are seen in breeding numbers in many populations of non-annual breeders. We examined the interannual variation in nesting numbers of populations of green (Chelonia mydas) (n = 16 populations), loggerhead (Caretta caretta) (n = 10 populations), leatherback (Dermochelys coriacea) (n = 9 populations) and hawksbill turtles (Eretmochelys imbricata) (n = 10 populations). Interannual variation was greatest in the green turtle. When comparing green and loggerhead turtles nesting in Cyprus we found that green turtles were more likely to change the interval between laying seasons and showed greater variation in the number of clutches laid in a season. We suggest that these differences are driven by the varying trophic statuses of the different species. Green turtles are herbivorous, feeding on sea grasses and macro-algae, and this primary production will be more tightly coupled with prevailing environmental conditions than the carnivorous diet of the loggerhead turtle.
Abstract.
Author URL.
Godley, B.J. Broderick, A.C. Austin, T. (2001). Two hundred years after a commercial marine turtle fishery: the current status of marine turtles nesting in the Cayman Islands. Oryx, 35, 145-152.
Hochscheid, S. Broderick, A.C. Godley, B.J. (2000). Diving behaviour of green turtles: dive depth, dive duration and activity levels. Marine Ecology Progress Series, 208, 297-298.
Godley, B.J. Reece, S. Downie, J.R. (2000). Incubation periods and sex ratios of green turtles: highly female biased hatchling production in the eastern Mediterranean. Marine Ecology Progress Series, 202, 273-281.
Adams, C.R. Broderick, A.C. Godley, B.J. (2000). The diving behaviour of green turtles at Ascension island. Animal Behaviour, 59, 577-586.
Thompson, D.R. Furness, R.W. (1999). Do heavy metal concentrations pose a threat to marine turtles from the Mediterranean Sea?. Mar Poll Bull, 38, 497-502.
Godley, B.J. Furness, R.W. Wells, D.E. (1999). Concentrations and Patterns of Organochlorine Contaminants in Marine Turtles from Mediterranean and Atlantic Waters. Marine Environmental Research, 47(2), 117-135.
Godley, B.J. (1999). Effect of tagging marine turtles on nesting behaviour and reproductive success. Animal Behaviour, 58, 587-591.
Godley, B.J. Broderick, A.C. (1999). Long-term thermal conditions on the nesting beaches of green turtles on Ascension Island. Marine Ecology Progress Series, 185, 297-299.
Godley, B.J. Broderick, A.C. Wilson, R.P. (1999). Reptilian diving: highly variable dive patterns in the green turtle (Chelonia mydas). Marine Ecology Progress Series, 185, 101-112.
Broderick, A.C. Moraghan, S. (1999). Short term effectiveness of Passive Integrated Transponders (PITs) used in the study of Mediterranean marine turtles. Chelonian Conservation and Biology, 3, 477-479.
Gucu, A.C. Broderick, A.C. Furness, R.W. (1998). Interaction between marine turtles and artisanal fisheries in the eastern Mediterranean: a probable cause for concern?. Zoology in the Middle East, 16, 49-64.
Casale, P. Bradai, M.N. Godley, B.J. (1998). Molecular Resolution of Marine Turtle Stock composition in fishery bycatch: a case study in the Mediterranean. Molecular Ecology, 7, 1529-1542.
Gaywood, M.J. Law, R.J. McCarthy, C.J. (1998). Patterns of Marine Turtle Mortality in British Waters (1992 - 1996) with Reference to Tissue Contaminant Levels. Journal of Marine Biological Association(UK), 78, 973-984.
Godley BJ, Gaywood MJ, Law RJ, Mccarthy CJ, Mckenzie C, Patterson IAP, Penrose RS, Reid RJ, Ross HM (1998). Patterns of marine turtle mortality in British waters (1992-1996) with reference to tissue contaminant levels.
Journal of the Marine Biological Association of the United Kingdom,
78(3), 973-984.
Abstract:
Patterns of marine turtle mortality in British waters (1992-1996) with reference to tissue contaminant levels
Mortality patterns of marine turtles entangled in fishing gear, found dead at sea or stranded dead on and around the coast of Britain in the period 1992-1996 are described. of a total of 38 dead turtles identified, 35 were leatherback turtles (Dermochelys coriacea) and three were loggerhead turtles (Caretta caretta). All D. coriacea were considered adults or subadults nearing sexual maturity. Six individuals were assessed as females, ten were classified as males and 19 were not sexed. Dermochelys coriacea (N=20 measured) ranged from 120 to 210 cm in curved carapace length (mean, 152 cm). The three C. caretta were juveniles, and ranged from 15 to 30 cm curved carapace length. Possible origins, causes of mortality and interactions with fisheries are discussed. In addition, contaminant levels were determined in the tissues of three D. coriacea. Concentrations of organic contaminants determined were found to be low.
Abstract.
Thompson, D.R. Waldron, S. Furness, R.W. (1998). The trophic status of marine turtles determined by stable isotope analysis. Marine Ecology Progress Series, 166, 277-284.
Reid SWJ, Godley BJ, Henderson SM, Lawrie GJ, Lloyd D, Small K, Swannie N, Thomas RL (1997). Ecology and behaviour of the feral donkey, equus asinus, population of the karpas peninsula, northern cyprus.
Zoology in the Middle East,
14(1), 27-36.
Abstract:
Ecology and behaviour of the feral donkey, equus asinus, population of the karpas peninsula, northern cyprus
The ecology and behaviour of a population of feral donkeys (Equus asinus) in the Karpas peninsula, northern Cyprus, was investigated. The population size in the area occupied by the donkeys was estimated by independent subjective assessment and by two mark and recapture techniques as being approximately 300 to 400 animals with a density of 8–10 animals/km2. It was concluded that subjective assessments after a period of familiarisation with the study area can provide estimates close to those obtained by other systematic sampling techniques. During daylight hours the donkeys were most frequently observed in groups of one to four animals although larger grazing associations were also formed. The animals exhibited features of social organisation typical of feral asses appropriate to the length of time the population had been established. In the Karpas, control measures should be implemented to prevent possible animal welfare problems. © 1997 Taylor & Francis Group, LLC.
Abstract.
Godley B (1997). Marine turtles in British waters.
VETERINARY RECORD,
140(5), 136-136.
Author URL.
Godley BJ, Smith SM, Clark PF, Taylor JD (1997). Molluscan and crustacean items in the diet of the loggerhead turtle, Caretta caretta (Linnaeus, 1758) [Testudines: Chelonidae] in the eastern Mediterranean. Journal of Molluscan Studies, 63(3), 474-476.
Smith, S.M. Clark, P.F. Taylor, J.D. (1997). Molluscan and crustacean items in the diet of the loggerhead turtle, Caretta caretta (Linnaeus, 1758) [Testudines: Chelonidae] in the eastern Mediterranean. Journal of Molluscan Studies, 63, 476-478.
Godley, B.J. (1997). Observations of reproductive behaviour of male green turtles (Chelonia mydas) at a nesting beach in Cyprus. Chelonian Conservation and Biology, 2(4), 615-616.
Godley, B.J. (1996). Population and nesting ecology of the green turtle, Chelonia mydas, and loggerhead turtle, Caretta caretta, in northern Cyprus. Zoology in the Middle East, 13, 27-46.