Publications by category
Journal articles
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
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
Witt M, Hawkes L, Pikesley SK, Doherty P, Solandt J-L, Speedie C, Johnson L, Henderson S, Inger R (In Press). Predicting habitat suitability for basking sharks (Cetorhinus maximus) in UK waters using ensemble ecological niche modelling. Journal of Sea Research
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
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
Parton KJ, Doherty PD, Parrish M, Shearer P, Myrick K, Shipley ON, Gallagher AJ (2023). Opportunistic camera surveys provide insight into discrete foraging behaviours in nurse sharks (Ginglymostoma cirratum).
Environmental Biology of Fishes,
106(1), 19-30.
Abstract:
Opportunistic camera surveys provide insight into discrete foraging behaviours in nurse sharks (Ginglymostoma cirratum)
Elasmobranch fishes (sharks, skates and rays) are some of the most morphologically and behaviourally diverse vertebrates on the planet, demonstrating a wide range of feeding strategies. The nurse shark (Ginglymostoma cirratum) is a large, widely distributed shark species which is commonly associated with tropical and subtropical reefs worldwide; yet it remains vastly understudied relative to other large species. To advance our understanding of nurse shark behaviour and ecology, we used opportunistic video observations gathered throughout the islands of Turks and Caicos from September 2020 to April 2021. We made 233 observations from 78 camera deployments and identified five behaviours, four of which were attributed to foraging. Stationary feeding behaviour was most commonly observed and strongly influenced by habitat type with a greater number of observations occurring on sand banks relative to reef habitat. Unique to this study was the first empirical description of pectoral positioning, by which individuals can position their body relative to a food-source through mobilization of the pectoral fins. We discuss these findings in relation to mechanical processes and kinematics, and the implications of expanding our knowledge of the functional role nurse sharks play in the transfer of energy across tropical seascapes.
Abstract.
Andrzejaczek S, Lucas TCD, Goodman MC, Hussey NE, Armstrong AJ, Carlisle A, Coffey DM, Gleiss AC, Huveneers C, Jacoby DMP, et al (2022). Diving into the vertical dimension of elasmobranch movement ecology.
Sci Adv,
8(33).
Abstract:
Diving into the vertical dimension of elasmobranch movement ecology.
Knowledge of the three-dimensional movement patterns of elasmobranchs is vital to understand their ecological roles and exposure to anthropogenic pressures. To date, comparative studies among species at global scales have mostly focused on horizontal movements. Our study addresses the knowledge gap of vertical movements by compiling the first global synthesis of vertical habitat use by elasmobranchs from data obtained by deployment of 989 biotelemetry tags on 38 elasmobranch species. Elasmobranchs displayed high intra- and interspecific variability in vertical movement patterns. Substantial vertical overlap was observed for many epipelagic elasmobranchs, indicating an increased likelihood to display spatial overlap, biologically interact, and share similar risk to anthropogenic threats that vary on a vertical gradient. We highlight the critical next steps toward incorporating vertical movement into global management and monitoring strategies for elasmobranchs, emphasizing the need to address geographic and taxonomic biases in deployments and to concurrently consider both horizontal and vertical movements.
Abstract.
Author URL.
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.
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).
Abstract:
Fulfilling global marine commitments; lessons learned from Gabon
AbstractAs part of the Post‐2020 Biodiversity Framework, nations are assessing progress over the past decade in addressing the underlying drivers that influence direct pressures on biodiversity and formulating new policies and strategies for the decade to come. For marine conservation, global marine protected area (MPA) coverage is still falling short of the 10% target set in 2010. Here we show that while this reflects a lack of progress in many low‐ and middle‐income countries, a few of these nations have met or exceeded international commitments. To provide an in‐depth explanation of how this was achieved in Gabon, we summarize the lessons learnt by our consortium of policy makers and practitioners who helped implement a comprehensive and ecologically representative network of 20 MPAs. We show the importance of creating a national framework, building long‐term stakeholder support, and focusing on research that guides implementation and policy; and outline a four‐step approach that countries and donors could use as an example to help meet international commitments. By responding to calls to share lessons learned to inform future Convention on Biological Diversity targets, we show how Gabon's experiences could inform change elsewhere.
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
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
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.
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.
Mov Ecol,
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.
Author URL.
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.
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
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.
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.
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
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.
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
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.
Reports
Bicknell A, Turner R, Metcalfe K, Doherty P, Callow M, Witt M (2016). Field manual for socio-economic, fisheries & marine vertebrate surveys in Myanmar.
Birth F, Pikesley S, Bicknell A, Callow M, Doherty P, Exeter O, Kerry C, Metcalfe K, Turner R, Witt M, et al (2016). Myanmar Marine Biodiversity Atlas.
Publications by year
In Press
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
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
Witt M, Hawkes L, Pikesley SK, Doherty P, Solandt J-L, Speedie C, Johnson L, Henderson S, Inger R (In Press). Predicting habitat suitability for basking sharks (Cetorhinus maximus) in UK waters using ensemble ecological niche modelling. Journal of Sea Research
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
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
2023
Parton KJ, Doherty PD, Parrish M, Shearer P, Myrick K, Shipley ON, Gallagher AJ (2023). Opportunistic camera surveys provide insight into discrete foraging behaviours in nurse sharks (Ginglymostoma cirratum).
Environmental Biology of Fishes,
106(1), 19-30.
Abstract:
Opportunistic camera surveys provide insight into discrete foraging behaviours in nurse sharks (Ginglymostoma cirratum)
Elasmobranch fishes (sharks, skates and rays) are some of the most morphologically and behaviourally diverse vertebrates on the planet, demonstrating a wide range of feeding strategies. The nurse shark (Ginglymostoma cirratum) is a large, widely distributed shark species which is commonly associated with tropical and subtropical reefs worldwide; yet it remains vastly understudied relative to other large species. To advance our understanding of nurse shark behaviour and ecology, we used opportunistic video observations gathered throughout the islands of Turks and Caicos from September 2020 to April 2021. We made 233 observations from 78 camera deployments and identified five behaviours, four of which were attributed to foraging. Stationary feeding behaviour was most commonly observed and strongly influenced by habitat type with a greater number of observations occurring on sand banks relative to reef habitat. Unique to this study was the first empirical description of pectoral positioning, by which individuals can position their body relative to a food-source through mobilization of the pectoral fins. We discuss these findings in relation to mechanical processes and kinematics, and the implications of expanding our knowledge of the functional role nurse sharks play in the transfer of energy across tropical seascapes.
Abstract.
2022
Andrzejaczek S, Lucas TCD, Goodman MC, Hussey NE, Armstrong AJ, Carlisle A, Coffey DM, Gleiss AC, Huveneers C, Jacoby DMP, et al (2022). Diving into the vertical dimension of elasmobranch movement ecology.
Sci Adv,
8(33).
Abstract:
Diving into the vertical dimension of elasmobranch movement ecology.
Knowledge of the three-dimensional movement patterns of elasmobranchs is vital to understand their ecological roles and exposure to anthropogenic pressures. To date, comparative studies among species at global scales have mostly focused on horizontal movements. Our study addresses the knowledge gap of vertical movements by compiling the first global synthesis of vertical habitat use by elasmobranchs from data obtained by deployment of 989 biotelemetry tags on 38 elasmobranch species. Elasmobranchs displayed high intra- and interspecific variability in vertical movement patterns. Substantial vertical overlap was observed for many epipelagic elasmobranchs, indicating an increased likelihood to display spatial overlap, biologically interact, and share similar risk to anthropogenic threats that vary on a vertical gradient. We highlight the critical next steps toward incorporating vertical movement into global management and monitoring strategies for elasmobranchs, emphasizing the need to address geographic and taxonomic biases in deployments and to concurrently consider both horizontal and vertical movements.
Abstract.
Author URL.
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.
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).
Abstract:
Fulfilling global marine commitments; lessons learned from Gabon
AbstractAs part of the Post‐2020 Biodiversity Framework, nations are assessing progress over the past decade in addressing the underlying drivers that influence direct pressures on biodiversity and formulating new policies and strategies for the decade to come. For marine conservation, global marine protected area (MPA) coverage is still falling short of the 10% target set in 2010. Here we show that while this reflects a lack of progress in many low‐ and middle‐income countries, a few of these nations have met or exceeded international commitments. To provide an in‐depth explanation of how this was achieved in Gabon, we summarize the lessons learnt by our consortium of policy makers and practitioners who helped implement a comprehensive and ecologically representative network of 20 MPAs. We show the importance of creating a national framework, building long‐term stakeholder support, and focusing on research that guides implementation and policy; and outline a four‐step approach that countries and donors could use as an example to help meet international commitments. By responding to calls to share lessons learned to inform future Convention on Biological Diversity targets, we show how Gabon's experiences could inform change elsewhere.
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
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
2021
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.
2020
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.
Mov Ecol,
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.
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.
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.
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
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.
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.
2019
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
2018
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.
2017
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
2016
Bicknell A, Turner R, Metcalfe K, Doherty P, Callow M, Witt M (2016). Field manual for socio-economic, fisheries & marine vertebrate surveys in Myanmar.
Birth F, Pikesley S, Bicknell A, Callow M, Doherty P, Exeter O, Kerry C, Metcalfe K, Turner R, Witt M, et al (2016). Myanmar Marine Biodiversity Atlas.
2014
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.