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Pinti J, Shatley M, Carlisle A, Block BA, Oliver MJ. Using pseudo-absence models to test for environmental selection in marine movement ecology: the importance of sample size and selection strength. MOVEMENT ECOLOGY 2022; 10:60. [PMID: 36581885 PMCID: PMC9798696 DOI: 10.1186/s40462-022-00362-1] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 08/26/2022] [Accepted: 12/19/2022] [Indexed: 06/17/2023]
Abstract
BACKGROUND Understanding the selection of environmental conditions by animals requires knowledge of where they are, but also of where they could have been. Presence data can be accurately estimated by direct sampling, sightings, or through electronic tag deployments. However, absence data are harder to determine because absences are challenging to measure in an uncontrolled setting. To address this problem, ecologists have developed different methods for generating pseudo-absence data relying on theoretical movement models. These null models represent the movement of environmentally naive individuals, creating a set of locations that animals could have been if they were not exhibiting environmental selection. METHODS Here, we use four different kinds of null animal movement models-Brownian motion, Lévy walks, Correlated random walks, and Joint correlated random walks to test the ability and power of each of these null movement models to serve as appropriate animal absence models. We use Kolmogorov-Smirnov tests to detect environmental selection using two data sets, one of simulated animal tracks biased towards warmer sea surface temperatures, and one of 57 observed blue shark tracks of unknown sea surface temperature selection. RESULTS The four different types of movement models showed minimal difference in the ability to serve as appropriate null models for environmental selection studies. Selection strength and sample size were more important in detecting true environmental selection. We show that this method can suffer from high false positive rates, especially in the case where animals are not selecting for specific environments. We provide estimates of test accuracy at different sample sizes and selection strengths to avoid false positives when using this method. CONCLUSION We show how movement models can be used to generate pseudo-absences and test for habitat selection in marine organisms. While this approach efficiently detects environmental selection in marine organisms, it cannot detect the underlying mechanisms driving this selection.
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Affiliation(s)
- Jérôme Pinti
- College of Earth, Ocean, and Environment, University of Delaware, Lewes, DE, 19958, USA.
| | - Matthew Shatley
- College of Earth, Ocean, and Environment, University of Delaware, Lewes, DE, 19958, USA
| | - Aaron Carlisle
- College of Earth, Ocean, and Environment, University of Delaware, Lewes, DE, 19958, USA
| | - Barbara A Block
- Hopkins Marine Station, Biology Department, Stanford University, Pacific Grove, CA, 93950, USA
| | - Matthew J Oliver
- College of Earth, Ocean, and Environment, University of Delaware, Lewes, DE, 19958, USA
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2
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Picard MMM, Johnson LE, Côté IM. Effects of sediment on spore performance as a potential constraint on kelp distribution. MARINE POLLUTION BULLETIN 2022; 185:114336. [PMID: 36372050 DOI: 10.1016/j.marpolbul.2022.114336] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/10/2022] [Revised: 09/24/2022] [Accepted: 10/31/2022] [Indexed: 06/16/2023]
Abstract
Kelp habitats contribute to marine productivity and diversity, making understanding the constraints on their distribution important. In the Gulf of St. Lawrence, Alaria esculenta occupies a subset of Saccharina latissima's range. Since tolerance to sedimentation by early life stages was suggested to cause this contrasting distribution, we tested the influence of sediment levels on spore attachment and development. For both species, the proportion of attached spores that developed decreased with increasing sediment. However, spore attachment and gametophyte density increased with sediment concentration but only for Saccharina. At the maximum sediment level examined, spore attachment and gametophyte densities of the two species were similar, contrary to the idea that sediment effects on early life stages explain differences in adult distribution. Further investigation, particularly with higher sediment loads, is required to confirm this conclusion. As turbidity is increasing globally, understanding the mechanisms underpinning changes in seaweed distribution will facilitate appropriate local-scale management.
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Affiliation(s)
- Manon M M Picard
- Department of Biological Sciences, Simon Fraser University, Burnaby, BC V5A 1S6, Canada.
| | - Ladd E Johnson
- Québec-Océan, Département de biologie, Université Laval, Québec, QC G1V 0A6, Canada
| | - Isabelle M Côté
- Department of Biological Sciences, Simon Fraser University, Burnaby, BC V5A 1S6, Canada
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3
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Net illumination reduces fisheries bycatch, maintains catch value, and increases operational efficiency. Curr Biol 2022; 32:911-918.e2. [PMID: 35063121 DOI: 10.1016/j.cub.2021.12.050] [Citation(s) in RCA: 6] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/20/2021] [Revised: 10/04/2021] [Accepted: 12/17/2021] [Indexed: 11/20/2022]
Abstract
Small-scale fisheries are vital for food security, nutrition, and livelihoods in coastal areas throughout the world's oceans.1-9 As intricately linked social-ecological systems, small-scale fisheries require management approaches that help ensure both ecological and socioeconomic sustainability.7,10-14 Given their ease of use and lucrative nature, coastal gillnet fisheries are globally ubiquitous.10,15 However, these fisheries often result in high discarded capture of non-target organisms (bycatch) that can lead to significant cascading effects throughout trophic chains16-18 and costly fisheries restrictions that result in important revenue losses in coastal communities with scarce economic alternatives.19,20 Despite these challenges, few solutions have been developed and broadly adopted to decrease bycatch in coastal gillnet fisheries, particularly in developing nations.5,21 Here we used controlled experiments along Mexico's Baja California peninsula to show that illuminating gillnets with green LED lights-an emerging technology originally developed to mitigate sea turtle bycatch-significantly reduced mean rates of total discarded bycatch biomass by 63%, which included significant decreases in elasmobranch (95%), Humboldt squid (81%), and unwanted finfish (48%). Moreover, illuminated nets significantly reduced the mean time required to retrieve and disentangle nets by 57%. In contrast, there were no significant differences in target fish catch or value. These findings advance our understanding of how artificial illumination affects operational efficiency and changes in catch rates in coastal gillnet fisheries, while illustrating the value of assessing broad-scale ecological and socioeconomic effects of species-specific conservation strategies.
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Morales-Zárate M, López-Ramírez J, Salinas-Zavala C. Loggerhead marine turtle (Caretta caretta) ecological facts from a trophic relationship model in a hot spot fishery area: Gulf of Ulloa, Mexico. Ecol Modell 2021. [DOI: 10.1016/j.ecolmodel.2020.109327] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/23/2022]
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Lavaniegos BE. Hyperiid amphipods from the Gulf of Ulloa and offshore region, Baja California: The possible role of the gelatinous zooplankton as a transport vector into the coastal shelf waters. PLoS One 2020; 15:e0233071. [PMID: 33151968 PMCID: PMC7643982 DOI: 10.1371/journal.pone.0233071] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/24/2020] [Accepted: 10/09/2020] [Indexed: 11/19/2022] Open
Abstract
Hyperiid amphipod species from the Gulf of Ulloa, Baja California, and the adjacent region (from the shelf break to 200 km offshore) were analyzed to evaluate diversity and abundances. This productive area supports small-scale commercial fisheries, including sand bass (Paralabrax nebulifer), California spiny lobster (Panulirus interruptus), abalones, clams, and others. Strong coastal upwelling events were observed during summer seasons of the period 2002-2008 between Punta Eugenia and Punta Abreojos. The upwelling plumes at Punta Abreojos are transported southward in slope waters bordering the coastal shelf of the Gulf of Ulloa, contributing to the separation of coastal and oceanic regions, and explain differences in amphipod diversity and abundances between both regions. In the offshore region, the most abundant species were Vibilia armata, Lestrigonus schizogeneios, Primno brevidens, and Eupronoe minuta, similar to previous findings in northern regions of Baja California and southern California. However, abundances of these species were lower (10-30 individuals/1000 m3), only reaching 20-50% of abundance levels reported off northern Baja California. In the coastal shelf of the Gulf of Ulloa, amphipods were virtually absent during 2002, 2003 and 2006. However, during 2004 and 2005, abundances of P. brevidens increased (54 and 20 ind/1000 m3, respectively). Moreover, during the late summer of 2007, abundances of L. schizogeneios, P. brevidens, Lycaea nasuta, Lycaea pulex, and Simorhynchotus antennarius increased considerably (261, 39, 31, 68, 416 ind/1000 m3, respectively), indicating occasional utilization of the coastal shelf by pelagic amphipods. Changes in gelatinous populations (medusae, siphonophores, ctenophores, doliolids, and salps) paralleled changes in hyperiid populations, with highest abundances in 2005-2008 in the coastal shelf. Significant correlations of 17 amphipod species with gelatinous taxa, which are often used as host organisms by hyperiid amphipods, suggest that gelatinous presence enhanced hyperiid abundance and promoted the progression of hyperiid amphipods onto the coastal shelf during parts of the 2002-2008 period.
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Affiliation(s)
- Bertha E. Lavaniegos
- Departamento de Oceanografía Biológica, Centro de Investigación Científica y Educación Superior de Ensenada, Baja California, México
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Maxwell SM, Scales KL, Bograd SJ, Briscoe DK, Dewar H, Hazen EL, Lewison RL, Welch H, Crowder LB. Seasonal spatial segregation in blue sharks (
Prionace glauca
) by sex and size class in the Northeast Pacific Ocean. DIVERS DISTRIB 2019. [DOI: 10.1111/ddi.12941] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/01/2022] Open
Affiliation(s)
- Sara M. Maxwell
- School of Interdisciplinary Arts and Sciences University of Washington Bothell Washington
- Department of Biological Sciences Old Dominion University Norfolk Virginia
| | - Kylie L. Scales
- Global Change Ecology Research Group University of the Sunshine Coast Maroochydore Australia
| | - Steven J. Bograd
- NOAA Southwest Fisheries Science Center, Environmental Research Division Monterey California
- Institute of Marine Sciences University of California Santa Cruz Santa Cruz California
| | - Dana K. Briscoe
- Hopkins Marine Station Stanford University Pacific Grove California
- National Institute of Water and Atmospheric Research Nelson New Zealand
| | - Heidi Dewar
- NOAA Southwest Fisheries Science Center La Jolla California
| | - Elliott L. Hazen
- NOAA Southwest Fisheries Science Center, Environmental Research Division Monterey California
- Institute of Marine Sciences University of California Santa Cruz Santa Cruz California
| | | | - Heather Welch
- NOAA Southwest Fisheries Science Center, Environmental Research Division Monterey California
- Institute of Marine Sciences University of California Santa Cruz Santa Cruz California
| | - Larry B. Crowder
- Hopkins Marine Station Stanford University Pacific Grove California
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Hays GC, Bailey H, Bograd SJ, Bowen WD, Campagna C, Carmichael RH, Casale P, Chiaradia A, Costa DP, Cuevas E, Nico de Bruyn PJ, Dias MP, Duarte CM, Dunn DC, Dutton PH, Esteban N, Friedlaender A, Goetz KT, Godley BJ, Halpin PN, Hamann M, Hammerschlag N, Harcourt R, Harrison AL, Hazen EL, Heupel MR, Hoyt E, Humphries NE, Kot CY, Lea JSE, Marsh H, Maxwell SM, McMahon CR, Notarbartolo di Sciara G, Palacios DM, Phillips RA, Righton D, Schofield G, Seminoff JA, Simpfendorfer CA, Sims DW, Takahashi A, Tetley MJ, Thums M, Trathan PN, Villegas-Amtmann S, Wells RS, Whiting SD, Wildermann NE, Sequeira AMM. Translating Marine Animal Tracking Data into Conservation Policy and Management. Trends Ecol Evol 2019; 34:459-473. [PMID: 30879872 DOI: 10.1016/j.tree.2019.01.009] [Citation(s) in RCA: 105] [Impact Index Per Article: 21.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/05/2018] [Revised: 01/21/2019] [Accepted: 01/22/2019] [Indexed: 11/18/2022]
Abstract
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.
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Affiliation(s)
| | - Helen Bailey
- Chesapeake Biological Laboratory, University of Maryland Center for Environmental Science, Solomons, MD 20688, USA
| | - Steven J Bograd
- NOAA Southwest Fisheries Science Center, Environmental Research Division, Monterey, CA 93940, USA
| | - W Don Bowen
- Population Ecology Division, Bedford Institute of Oceanography, Dartmouth, NS B2Y 4A2, Canada
| | - Claudio Campagna
- Wildlife Conservation Society, Marine Program, Buenos Aires, 1414 Argentina
| | - Ruth H Carmichael
- University Programs, Dauphin Island Sea Lab, Dauphin Island, AL 36528, USA; Department of Marine Sciences, University of South Alabama, Mobile, AL 36688, USA
| | - Paolo Casale
- Department of Biology, University of Pisa, Pisa, Italy
| | - Andre Chiaradia
- Conservation Department, Phillip Island, Nature Parks, Victoria, Australia
| | - Daniel P Costa
- Department of Ecology and Evolutionary Biology, University of California, Santa Cruz, CA 95060, USA
| | - Eduardo Cuevas
- CONACYT - Research Center of Environmental Sciences, Faculty of Natural Sciences, Universidad Autonoma del Carmen, Campeche 24180, Mexico; Pronatura Peninsula de Yucatan, Yucatan 97205, Mexico
| | - P J Nico de Bruyn
- Mammal Research Institute, Department of Zoology & Entomology, University of Pretoria, Hatfield 0028, South Africa
| | - Maria P Dias
- BirdLife International, Cambridge CB2 3QZ, UK; MARE - Marine and Environmental Sciences Center, ISPA - Instituto Universitário, 1149-041 Lisboa, Portugal
| | - Carlos M Duarte
- King Abdullah University of Science and Technology (KAUST), Red Sea Research Center (RSRC), Thuwal, 23955-6900, Saudi Arabia
| | - Daniel C Dunn
- Marine Geospatial Ecology Lab, Nicholas School of the Environment, Duke University, Durham, NC, USA
| | - Peter H Dutton
- Marine Mammal and Turtle Division, National Marine Fisheries Service, National Oceanic and Atmospheric Administration, La Jolla, CA 92037, USA
| | - Nicole Esteban
- Department of Biosciences, Swansea University, Swansea SA2 8PP, Wales, UK
| | - Ari Friedlaender
- Department of Ecology and Evolutionary Biology, University of California, Santa Cruz, CA 95060, USA; Institute for Marine Sciences, University of California Santa Cruz, Santa Cruz, CA 965060, USA
| | - Kimberly T Goetz
- National Institute of Water & Atmospheric Research Ltd (NIWA),Greta Point, Wellington, New Zealand
| | - Brendan J Godley
- Marine Turtle Research Group, Centre for Ecology and Conservation, School of Biosciences, University of Exeter, Cornwall Campus, Penryn TR10 9EZ, UK
| | - Patrick N Halpin
- Marine Geospatial Ecology Lab, Nicholas School of the Environment, Duke University, Durham, NC, USA
| | - Mark Hamann
- College of Science and Engineering, James Cook University, Townsville, QLD 4811, Australia
| | - Neil Hammerschlag
- Rosenstiel School of Marine & Atmospheric Science, Abess Center for Ecosystem Science & Policy, University of Miami, Miami, FL 33149, USA
| | - Robert Harcourt
- Department of Biological Sciences, Macquarie University, Sydney, NSW 2109, Australia
| | - Autumn-Lynn Harrison
- Migratory Bird Center, Smithsonian Conservation Biology Institute, Washington, DC 20008, USA
| | - Elliott L Hazen
- NOAA Southwest Fisheries Science Center, Environmental Research Division, Monterey, CA 93940, USA
| | - Michelle R Heupel
- Australian Institute of Marine Science, Townsville, QLD 4810, Australia
| | - Erich Hoyt
- Whale and Dolphin Conservation, Bridport, Dorset, UK; IUCN Joint SSC/WCPA Marine Mammal Protected Areas Task Force, Gland, Switzerland
| | - Nicolas E Humphries
- Marine Biological Association of the United Kingdom, The Laboratory, Plymouth PL1 2PB, UK
| | - Connie Y Kot
- Marine Geospatial Ecology Lab, Nicholas School of the Environment, Duke University, Durham, NC, USA
| | - James S E Lea
- Department of Zoology, University of Cambridge, Cambridge, UK
| | - Helene Marsh
- College of Science and Engineering, James Cook University, Townsville, QLD 4811, Australia
| | - Sara M Maxwell
- School of Interdisciplinary Arts and Sciences, University of Washington, Bothell Campus, Bothell, WA 98011, USA
| | - Clive R McMahon
- Department of Biological Sciences, Macquarie University, Sydney, NSW 2109, Australia; Ecology and Biodiversity Centre, Institute for Marine and Antarctic Studies, University of Tasmania, Hobart, TAS 7004, Australia; Sydney Institute of Marine Science, Mosman, NSW 2088, Australia
| | - Giuseppe Notarbartolo di Sciara
- Tethys Research Institute, 20121 Milano, Italy; IUCN Joint SSC/WCPA Marine Mammal Protected Areas Task Force, Gland, Switzerland
| | - Daniel M Palacios
- Marine Mammal Institute and Department of Fisheries and Wildlife, Oregon State University, Newport, OR 97365, USA
| | - Richard A Phillips
- British Antarctic Survey, Natural Environment Research Council, Cambridge, CB3 0ET, UK
| | - David Righton
- Cefas Laboratory, Suffolk, NR33 0HT, UK; School of Environmental Sciences, University of East Anglia, Norwich, NR4 7TJ, UK
| | - Gail Schofield
- School of Biological and Chemical Sciences, Queen Mary University of London, E14NS, London, UK
| | - Jeffrey A Seminoff
- Marine Turtle Ecology and Assessment Program, NOAA-Southwest Fisheries Science Center, La Jolla, CA 92037, USA
| | - Colin A Simpfendorfer
- College of Science and Engineering, James Cook University, Townsville, QLD 4811, Australia
| | - David W Sims
- Marine Biological Association of the United Kingdom, The Laboratory, Plymouth PL1 2PB, UK; Ocean and Earth Science, National Oceanography Centre Southampton, University of Southampton, Waterfront Campus, Southampton, SO14 3ZH, UK; Centre for Biological Sciences, Building 85, University of Southampton, Highfield Campus, Southampton, SO17 1BJ, UK
| | - Akinori Takahashi
- National Institute of Polar Research, Tachikawa, Tokyo 190-8518, Japan
| | - Michael J Tetley
- IUCN Joint SSC/WCPA Marine Mammal Protected Areas Task Force, Gland, Switzerland
| | - Michele Thums
- Australian Institute of Marine Science, Indian Ocean Marine Research Centre (M096), University of Western Australia, Crawley, WA 6009, Australia
| | - Philip N Trathan
- IUCN Joint SSC/WCPA Marine Mammal Protected Areas Task Force, Gland, Switzerland
| | - Stella Villegas-Amtmann
- Department of Ecology and Evolutionary Biology, University of California, Santa Cruz, CA 95060, USA
| | - Randall S Wells
- Chicago Zoological Society's Sarasota Dolphin Research Program, c/o Mote Marine Laboratory, Sarasota, FL 34236, USA
| | - Scott D Whiting
- Marine Science Program, Department of Biodiversity, Conservation, and Attractions, Kensington, WA 6151, Australia
| | - Natalie E Wildermann
- Marine Turtle Research, Ecology and Conservation Group, Department of Earth, Ocean and Atmospheric, Science, Florida State University, Tallahassee, FL 32306-4320, USA
| | - Ana M M Sequeira
- IOMRC and The University of Western Australia Oceans Institute, School of Biological Sciences, University of Western Australia, Crawley, WA 6009, Australia
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Zuercher R, Galloway AWE. Coastal marine ecosystem connectivity: pelagic ocean to kelp forest subsidies. Ecosphere 2019. [DOI: 10.1002/ecs2.2602] [Citation(s) in RCA: 17] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022] Open
Affiliation(s)
- Rachel Zuercher
- University of California Santa Cruz Santa Cruz California 95060 USA
| | - Aaron W. E. Galloway
- Oregon Institute of Marine Biology University of Oregon Charleston Oregon 97420 USA
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Palacios DM, Bailey H, Becker EA, Bograd SJ, DeAngelis ML, Forney KA, Hazen EL, Irvine LM, Mate BR. Ecological correlates of blue whale movement behavior and its predictability in the California Current Ecosystem during the summer-fall feeding season. MOVEMENT ECOLOGY 2019; 7:26. [PMID: 31360521 PMCID: PMC6637557 DOI: 10.1186/s40462-019-0164-6] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/23/2018] [Accepted: 05/26/2019] [Indexed: 05/12/2023]
Abstract
BACKGROUND Species distribution models have shown that blue whales (Balaenoptera musculus) occur seasonally in high densities in the most biologically productive regions of the California Current Ecosystem (CCE). Satellite telemetry studies have additionally shown that blue whales in the CCE regularly switch between behavioral states consistent with area-restricted searching (ARS) and transiting, indicative of foraging in and moving among prey patches, respectively. However, the relationship between the environmental correlates that serve as a proxy of prey relative to blue whale movement behavior has not been quantitatively assessed. METHODS We investigated the association between blue whale behavioral state and environmental predictors in the coastal environments of the CCE using a long-term satellite tracking data set (72 tagged whales; summer-fall months 1998-2008), and predicted the likelihood of ARS behavior at tracked locations using nonparametric multiplicative regression models. The models were built using data from years of cool, productive conditions and validated against years of warm, low-productivity conditions. RESULTS The best model contained four predictors: chlorophyll-a, sea surface temperature, and seafloor aspect and depth. This model estimated highest ARS likelihood (> 0.8) in areas with high chlorophyll-a levels (> 0.65 mg/m3), intermediate sea surface temperatures (11.6-17.5 °C), and shallow depths (< 850 m). Overall, the model correctly predicted behavioral state throughout the coastal environments of the CCE, while the validation indicated an ecosystem-wide reduction in ARS likelihood during warm years, especially in the southern portion. For comparison, a spatial coordinates model (longitude × latitude) performed slightly better than the environmental model during warm years, providing further evidence that blue whales exhibit strong foraging site fidelity, even when conditions are not conducive to successful foraging. CONCLUSIONS We showed that blue whale behavioral state in the CCE was predictable from environmental correlates and that ARS behavior was most prevalent in regions of known high whale density, likely reflecting where large prey aggregations consistently develop in summer-fall. Our models of whale movement behavior enhanced our understanding of species distribution by further indicating where foraging was more likely, which could be of value in the identification of key regions of importance for endangered species in management considerations. The models also provided evidence that decadal-scale environmental fluctuations can drive shifts in the distribution and foraging success of this blue whale population.
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Affiliation(s)
- Daniel M. Palacios
- Marine Mammal Institute and Department of Fisheries and Wildlife, Hatfield Marine Science Center, Oregon State University, Newport, OR USA
| | - Helen Bailey
- Chesapeake Biological Laboratory, University of Maryland Center for Environmental Science, Solomons, MD USA
| | - Elizabeth A. Becker
- Marine Mammal and Turtle Division, Southwest Fisheries Science Center, National Marine Fisheries Service, National Oceanic and Atmospheric Administration, La Jolla, CA USA
| | - Steven J. Bograd
- Environmental Research Division, Southwest Fisheries Science Center, National Marine Fisheries Service, National Oceanic and Atmospheric Administration, Monterey, CA USA
| | - Monica L. DeAngelis
- NOAA West Coast Regional Office, Long Beach, CA USA
- Present Address: Naval Undersea Warfare Center, Newport, RI USA
| | - Karin A. Forney
- Marine Mammal and Turtle Division, Southwest Fisheries Science Center, National Marine Fisheries Service, National Oceanic and Atmospheric Administration, Moss Landing, CA USA
- Moss Landing Marine Laboratories, Moss Landing, CA USA
| | - Elliott L. Hazen
- Environmental Research Division, Southwest Fisheries Science Center, National Marine Fisheries Service, National Oceanic and Atmospheric Administration, Monterey, CA USA
- University of California Santa Cruz, Santa Cruz, CA USA
| | - Ladd M. Irvine
- Marine Mammal Institute and Department of Fisheries and Wildlife, Hatfield Marine Science Center, Oregon State University, Newport, OR USA
| | - Bruce R. Mate
- Marine Mammal Institute and Department of Fisheries and Wildlife, Hatfield Marine Science Center, Oregon State University, Newport, OR USA
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10
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Oceanographic and Bathymetric Features as the Target for Pelagic MPA Design: A Case Study on the Cape of Gata. WATER 2018. [DOI: 10.3390/w10101403] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
Abstract
The Cape of Gata region (southeast Spain) allocates the thermo-haline Almeria–Oran front (AOF), which separates two biogeographical zones, with a very irregular bathymetry, consisting of two canyons and seamounts in an area of 100 × 100 km. An interdisciplinary oceanographic sampling strategy allowed us to solve mesoscale processes including current–bathymetry interactions. Subsurface fertilizing processes and elevated chlorophyll a concentrations were found at the front, seamount, and submarine canyons, turning an apparently oligotrophic area into a rich one. According to a horizontal tracking simulation, the deep chlorophyll maximum (DCM) at the front is located above the pycnocline and travels fast offshore, transporting productivity from the fertilization process quickly from the region. The DCM at the seamount, in contrast, develops below the pycnocline and remains for almost three weeks in this area. In spite of the coastal marine protected areas (MPAs), a high surface nitrate concentration plume with its origin in a small coastal area without any protection was detected. Local circulation patterns and bathymetry–current interactions provide elevated productivity in surface water which is vertically connected to deep-sea fauna via the daily vertical migration of zooplankton, suggesting elevated biodiversity on the seamount and canyons of the area studied. Based on these results, and considering the presence of coastal MPAs and a Coastal Area Management Program, future studies on benthic fauna, an enlargement of coastal MPAs, and a transboundary land–deep-sea management program are suggested.
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11
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Behera S, Tripathy B, Choudhury BC, Sivakumar K. Movements of Olive Ridley Turtles (Lepidochelys olivacea) in the Bay of Bengal, India, Determined via Satellite Telemetry. CHELONIAN CONSERVATION AND BIOLOGY 2018. [DOI: 10.2744/ccb-1245.1] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
Affiliation(s)
- Satyaranjan Behera
- Odisha Biodiversity Board, Regional Plant Resource Centre Campus, Nayapalli, Bhubaneswar-15, Odisha, India []
| | - Basudev Tripathy
- Zoological Survey of India, M-Block, New Alipore, Kolkata – 700 053, West Bengal, India []
| | | | - Kupuswamy Sivakumar
- Wildlife Institute of India, Chandrabani, Dehradun – 248 001, Uttarakhand, India []
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12
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Briscoe DK, Parker DM, Balazs GH, Kurita M, Saito T, Okamoto H, Rice M, Polovina JJ, Crowder LB. Active dispersal in loggerhead sea turtles (Caretta caretta) during the 'lost years'. Proc Biol Sci 2017; 283:rspb.2016.0690. [PMID: 27252021 DOI: 10.1098/rspb.2016.0690] [Citation(s) in RCA: 35] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/24/2016] [Accepted: 05/09/2016] [Indexed: 11/12/2022] Open
Abstract
Highly migratory marine species can travel long distances and across entire ocean basins to reach foraging and breeding grounds, yet gaps persist in our knowledge of oceanic dispersal and habitat use. This is especially true for sea turtles, whose complex life history and lengthy pelagic stage present unique conservation challenges. Few studies have explored how these young at-sea turtles navigate their environment, but advancements in satellite technology and numerical models have shown that active and passive movements are used in relation to open ocean features. Here, we provide the first study, to the best of our knowledge, to simultaneously combine a high-resolution physical forcing ocean circulation model with long-term multi-year tracking data of young, trans-oceanic North Pacific loggerhead sea turtles during their 'lost years' at sea. From 2010 to 2014, we compare simulated trajectories of passive transport with empirical data of 1-3 year old turtles released off Japan (29.7-37.5 straight carapace length cm). After several years, the at-sea distribution of simulated current-driven trajectories significantly differed from that of the observed turtle tracks. These results underscore current theories on active dispersal by young oceanic-stage sea turtles and give further weight to hypotheses of juvenile foraging strategies for this species. Such information can also provide critical geographical information for spatially explicit conservation approaches to this endangered population.
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Affiliation(s)
- D K Briscoe
- Biology, Stanford University, Hopkins Marine Station, 120 Oceanview Boulevard, Pacific Grove, CA 93950, USA
| | - D M Parker
- Joint Institute for Marine and Atmospheric Research, National Oceanic and Atmospheric Administration, 2032 Southeast Oregon State University Drive, Newport, OR 97365, USA
| | - G H Balazs
- Pacific Islands Fisheries Science Center, National Oceanic and Atmospheric Administration Inouye Regional Center, National Marine Fisheries Service, 1845 WASP Boulevard Building 176, Honolulu, HI 96818, USA
| | - M Kurita
- Port of Nagoya Public Aquarium, Minato-ku, Nagoya 455-0033, Japan
| | - T Saito
- Usa Marine Biological Institute, Kochi University, Usa Tosa, Kochi 781-1164, Japan
| | - H Okamoto
- Port of Nagoya Public Aquarium, Minato-ku, Nagoya 455-0033, Japan
| | - M Rice
- Hawaii Preparatory Academy, 65-1692 Kohala Mountain Road, Kamuela, HI 96743, USA
| | - J J Polovina
- Port of Nagoya Public Aquarium, Minato-ku, Nagoya 455-0033, Japan
| | - L B Crowder
- Biology, Stanford University, Hopkins Marine Station, 120 Oceanview Boulevard, Pacific Grove, CA 93950, USA Center for Ocean Solutions, Stanford University, 99 Pacific Street, Suite 555E, Monterey, CA 93949, USA
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13
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McDonald TL, Hornsby FE, Speakman TR, Zolman ES, Mullin KD, Sinclair C, Rosel PE, Thomas L, Schwacke LH. Survival, density, and abundance of common bottlenose dolphins in Barataria Bay (USA) following the Deepwater Horizon oil spill. ENDANGER SPECIES RES 2017. [DOI: 10.3354/esr00806] [Citation(s) in RCA: 32] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022] Open
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14
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Turner Tomaszewicz CN, Seminoff JA, Peckham SH, Avens L, Kurle CM. Intrapopulation variability in the timing of ontogenetic habitat shifts in sea turtles revealed using δ 15 N values from bone growth rings. J Anim Ecol 2017; 86:694-704. [PMID: 28075017 DOI: 10.1111/1365-2656.12618] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/31/2016] [Accepted: 11/24/2016] [Indexed: 11/29/2022]
Abstract
Determining location and timing of ontogenetic shifts in the habitat use of highly migratory species, along with possible intrapopulation variation in these shifts, is essential for understanding mechanisms driving alternate life histories and assessing overall population trends. Measuring variations in multi-year habitat-use patterns is especially difficult for remote oceanic species. To investigate the potential for differential habitat use among migratory marine vertebrates, we measured the naturally occurring stable nitrogen isotope (δ15 N) patterns that differentiate distinct ocean regions to create a 'regional isotope characterization', analysed the δ15 N values from annual bone growth layer rings from dead-stranded animals, and then combined the bone and regional isotope data to track individual animal movement patterns over multiple years. We used humeri from juvenile North Pacific loggerhead turtles (Caretta caretta), animals that undergo long migrations across the North Pacific Ocean (NPO), using multiple discrete regions as they develop to adulthood. Typical of many migratory marine species, ontogenetic changes in habitat use throughout their decades-long juvenile stage is poorly understood, but each potential habitat has unique foraging opportunities and spatially explicit natural and anthropogenic threats that could affect key life-history parameters. We found a bimodal size/age distribution in the timing that juveniles underwent an ontogenetic habitat shift from the oceanic central North Pacific (CNP) to the neritic east Pacific region near the Baja California Peninsula (BCP) (42·7 ± 7·2 vs. 68·3 ± 3·4 cm carapace length, 7·5 ± 2·7 vs. 15·6 ± 1·7 years). Important to the survival of this population, these disparate habitats differ considerably in their food availability, energy requirements and threats, and these differences can influence life-history parameters such as growth, survival and future fecundity. This is the first evidence of alternative ontogenetic shifts and habitat-use patterns for juveniles foraging in the eastern NPO. We combine two techniques, skeletochronology and stable isotope analysis, to reconstruct multi-year habitat-use patterns of a remote migratory species, linked to estimated ages and body sizes of individuals, to reveal variable ontogeny during the juvenile life stage that could drive alternate life histories and that has the potential to illuminate the migration patterns for other species with accretionary tissues.
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Affiliation(s)
- Calandra N Turner Tomaszewicz
- Division of Biological Sciences, Ecology, Behavior, and Evolution Section, University of California, La Jolla, CA, 92093, USA.,Southwest Fisheries Science Center, NOAA-National Marine Fisheries Service, La Jolla, CA, 92037, USA
| | - Jeffrey A Seminoff
- Southwest Fisheries Science Center, NOAA-National Marine Fisheries Service, La Jolla, CA, 92037, USA
| | - S Hoyt Peckham
- Center for Ocean Solutions, Stanford University, Pacific Grove, CA, 93950, USA
| | - Larisa Avens
- Southeast Fisheries Science Center, NOAA-National Marine Fisheries Service, Beaufort, NC, 28516, USA
| | - Carolyn M Kurle
- Division of Biological Sciences, Ecology, Behavior, and Evolution Section, University of California, La Jolla, CA, 92093, USA
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15
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Quantifying overlap between the Deepwater Horizon oil spill and predicted bluefin tuna spawning habitat in the Gulf of Mexico. Sci Rep 2016; 6:33824. [PMID: 27654709 PMCID: PMC5031980 DOI: 10.1038/srep33824] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/23/2016] [Accepted: 09/02/2016] [Indexed: 01/26/2023] Open
Abstract
Atlantic bluefin tuna (Thunnus thynnus) are distributed throughout the North Atlantic and are both economically valuable and heavily exploited. The fishery is currently managed as two spawning populations, with the GOM population being severely depleted for over 20 years. In April-August of 2010, the Deepwater Horizon oil spill released approximately 4 million barrels of oil into the GOM, with severe ecosystem and economic impacts. Acute oil exposure results in mortality of bluefin eggs and larvae, while chronic effects on spawning adults are less well understood. Here we used 16 years of electronic tagging data for 66 bluefin tuna to identify spawning events, to quantify habitat preferences, and to predict habitat use and oil exposure within Gulf of Mexico spawning grounds. More than 54,000 km2 (5%) of predicted spawning habitat within the US EEZ was oiled during the week of peak oil dispersal, with potentially lethal effects on eggs and larvae. Although the oil spill overlapped with a relatively small portion of predicted spawning habitat, the cumulative impact from oil, ocean warming and bycatch mortality on GOM spawning grounds may result in significant effects for a population that shows little evidence of rebuilding.
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16
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Wedding LM, Maxwell SM, Hyrenbach D, Dunn DC, Roberts JJ, Briscoe D, Hines E, Halpin PN. Geospatial approaches to support pelagic conservation planning and adaptive management. ENDANGER SPECIES RES 2016. [DOI: 10.3354/esr00716] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022] Open
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17
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Peckham SH, Lucero-Romero J, Maldonado-Díaz D, Rodríguez-Sánchez A, Senko J, Wojakowski M, Gaos A. Buoyless Nets Reduce Sea Turtle Bycatch in Coastal Net Fisheries. Conserv Lett 2015. [DOI: 10.1111/conl.12176] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022] Open
Affiliation(s)
- S. Hoyt Peckham
- Center for Ocean Solutions; Stanford University; Pacific Grove CA USA
| | - Jesus Lucero-Romero
- Grupo Tortuguero de las Californias; A.C; La Paz, Baja California Sur México
| | | | | | - Jesse Senko
- School of Life Sciences; Arizona State University; Tempe AZ USA
| | | | - Alexander Gaos
- Eastern Pacific Hawksbill Initiative; San Diego CA USA
- San Diego State University; San Diego CA USA
- University of California Davis; Davis CA USA
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18
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Tomaszewicz CNT, Seminoff JA, Avens L, Goshe LR, Peckham SH, Rguez-Baron JM, Bickerman K, Kurle CM. Age and residency duration of loggerhead turtles at a North Pacific bycatch hotspot using skeletochronology. BIOLOGICAL CONSERVATION 2015; 186:134-142. [PMID: 25848136 PMCID: PMC4384431 DOI: 10.1016/j.biocon.2015.03.015] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/21/2023]
Abstract
For migratory marine animals, like sea turtles, effective conservation can be challenging because key demographic information such as duration of life stages and exposure to spatially explicit threats in different habitats are often unknown. In the eastern Pacific near the Baja California Peninsula (BCP), Mexico, tens of thousands of endangered North Pacific loggerhead sea turtles (Caretta caretta) concentrate at a foraging area known to have high rates of fishery bycatch. Because stage survivorship of loggerheads in the BCP will vary significantly depending on the number of years spent in this region, we applied skeletochronology to empirically estimate residency duration in this loggerhead hotspot. The observed age distribution obtained from skeletochronology analysis of 146 dead-stranded loggerheads ranged from three to 24 years old, suggesting a BCP residency of >20 years. Given the maximum estimated age and a one-year migration to western Pacific nesting beaches, we infer age-at-maturation for BCP loggerheads at ~25 years old. We also examine survivorship at varying BCP residency durations by applying our findings to current annual mortality estimates. Predicted survivorship of loggerheads spending over 20 years in this BCP foraging habitat is less than 10%, and given that ~43,000 loggerhead turtles forage here, a significant number of turtles are at extreme risk in this region. This is the first empirical evidence supporting estimated age-at-maturation for BCP North Pacific loggerheads, and the first estimates of BCP stage survivorship. Our findings emphasize the urgent need for continued and effective international conservation efforts to minimize bycatch of this endangered species.
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Affiliation(s)
- Calandra N. Turner Tomaszewicz
- Division of Biological Sciences, Ecology, Behavior, and Evolution Section, University of California, San Diego, La Jolla, CA 92093-0116, USA
- Southwest Fisheries Science Center, NOAA-National Marine Fisheries Service, La Jolla, California 92037, USA
- Corresponding Author: CTT, , 858-334-2842 Address: University of California, San Diego, 9500 Gilman Dr., La Jolla, CA 92093-0116
| | - Jeffrey A. Seminoff
- Southwest Fisheries Science Center, NOAA-National Marine Fisheries Service, La Jolla, California 92037, USA
| | - Larisa Avens
- Southeast Fisheries Science Center, NOAA, National Marine Fisheries Service, Beaufort, North Carolina 28516, USA
| | - Lisa R. Goshe
- Southeast Fisheries Science Center, NOAA, National Marine Fisheries Service, Beaufort, North Carolina 28516, USA
| | - S. Hoyt Peckham
- Center for Ocean Solutions, Stanford University, Pacific Grove, California 93940, USA
| | - Juan M. Rguez-Baron
- Marine Biology Department, Universidad Autonoma de Baja California Sur., La Paz, Baja California Sur, Mexico
| | - Kalyn Bickerman
- School of Biology and Ecology, University of Maine, Orono, Maine 04469, USA
| | - Carolyn M. Kurle
- Division of Biological Sciences, Ecology, Behavior, and Evolution Section, University of California, San Diego, La Jolla, CA 92093-0116, USA
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19
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20
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Scales KL, Miller PI, Hawkes LA, Ingram SN, Sims DW, Votier SC. REVIEW: On the Front Line: frontal zones as priority at-sea conservation areas for mobile marine vertebrates. J Appl Ecol 2014. [DOI: 10.1111/1365-2664.12330] [Citation(s) in RCA: 135] [Impact Index Per Article: 13.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Affiliation(s)
- Kylie L. Scales
- Plymouth Marine Laboratory; Prospect Place Plymouth PL1 3DH UK
| | - Peter I. Miller
- Plymouth Marine Laboratory; Prospect Place Plymouth PL1 3DH UK
| | - Lucy A. Hawkes
- Environment and Sustainability Institute; University of Exeter; Cornwall Campus Penryn TR10 9EZ UK
| | - Simon N. Ingram
- Centre for Marine and Coastal Policy Research; Plymouth University; Plymouth PL4 8AA UK
| | - David W. Sims
- Marine Biological Association of the United Kingdom; The Laboratory; Citadel Hill Plymouth PL1 2PB UK
- Ocean and Earth Science; University of Southampton; Waterfront Campus Southampton SO14 3ZH UK
| | - Stephen C. Votier
- Environment and Sustainability Institute; University of Exeter; Cornwall Campus Penryn TR10 9EZ UK
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21
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Seminoff JA, Eguchi T, Carretta J, Allen CD, Prosperi D, Rangel R, Gilpatrick JW, Forney K, Peckham SH. Loggerhead sea turtle abundance at a foraging hotspot in the eastern Pacific Ocean: implications for at-sea conservation. ENDANGER SPECIES RES 2014. [DOI: 10.3354/esr00601] [Citation(s) in RCA: 48] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022] Open
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22
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Palacios DM, Baumgartner MF, Laidre KL, Gregr EJ. Beyond correlation: integrating environmentally and behaviourally mediated processes in models of marine mammal distributions. ENDANGER SPECIES RES 2013. [DOI: 10.3354/esr00558] [Citation(s) in RCA: 48] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022] Open
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23
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Cumulative human impacts on marine predators. Nat Commun 2013; 4:2688. [DOI: 10.1038/ncomms3688] [Citation(s) in RCA: 177] [Impact Index Per Article: 16.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/26/2013] [Accepted: 09/30/2013] [Indexed: 11/09/2022] Open
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24
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Pikesley SK, Maxwell SM, Pendoley K, Costa DP, Coyne MS, Formia A, Godley BJ, Klein W, Makanga-Bahouna J, Maruca S, Ngouessono S, Parnell RJ, Pemo-Makaya E, Witt MJ. On the front line: integrated habitat mapping for olive ridley sea turtles in the southeast Atlantic. DIVERS DISTRIB 2013. [DOI: 10.1111/ddi.12118] [Citation(s) in RCA: 44] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022] Open
Affiliation(s)
- Stephen K. Pikesley
- Centre for Ecology and Conservation; University of Exeter; Cornwall UK
- Environment and Sustainability Institute; University of Exeter; Cornwall UK
| | - Sara M. Maxwell
- Hopkins Marine Station; Stanford University; Pacific Grove CA USA
| | | | - Daniel P. Costa
- Department of Ecology and Evolutionary Biology; University of California Santa Cruz; Santa Cruz CA USA
| | - Michael S. Coyne
- Centre for Ecology and Conservation; University of Exeter; Cornwall UK
- SEATURTLE.org; Durham NC USA
| | - Angela Formia
- Wildlife Conservation Society; Global Conservation Program; New York NY USA
| | - Brendan J. Godley
- Centre for Ecology and Conservation; University of Exeter; Cornwall UK
| | | | | | - Sheryl Maruca
- Chevron Energy Technology Company; Houston TX 77042 USA
| | | | | | | | - Matthew J. Witt
- Environment and Sustainability Institute; University of Exeter; Cornwall UK
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25
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Koch V, Peckham H, Mancini A, Eguchi T. Estimating at-sea mortality of marine turtles from stranding frequencies and drifter experiments. PLoS One 2013; 8:e56776. [PMID: 23483880 PMCID: PMC3577704 DOI: 10.1371/journal.pone.0056776] [Citation(s) in RCA: 46] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/20/2012] [Accepted: 01/15/2013] [Indexed: 11/19/2022] Open
Abstract
Strandings of marine megafauna can provide valuable information on cause of death at sea. However, as stranding probabilities are usually very low and highly variable in space and time, interpreting the results can be challenging. We evaluated the magnitude and distribution of at-sea mortality of marine turtles along the Pacific coast of Baja California Sur, México during 2010–11, using a combination of counting stranded animals and drifter experiments. A total of 594 carcasses were found during the study period, with loggerhead (62%) and green turtles (31%) being the most common species. 87% of the strandings occurred in the southern Gulf of Ulloa, a known hotspot of loggerhead distribution in the Eastern Pacific. While only 1.8% of the deaths could be definitively attributed to bycatch (net marks, hooks), seasonal variation in stranding frequencies closely corresponded to the main fishing seasons. Estimated stranding probabilities from drifter experiments varied among sites and trials (0.05–0.8), implying that only a fraction of dead sea turtles can be observed at beaches. Total mortality estimates for 15-day periods around the floater trials were highest for PSL, a beach in the southern Gulf of Ulloa, ranging between 11 sea turtles in October 2011 to 107 in August 2010. Loggerhead turtles were the most numerous, followed by green and olive ridley turtles. Our study showed that drifter trials combined with beach monitoring can provide estimates for death at sea to measure the impact of small-scale fisheries that are notoriously difficult to monitor for by-catch. We also provided recommendations to improve the precision of the mortality estimates for future studies and highlight the importance of estimating impacts of small–scale fisheries on marine megafauna.
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Affiliation(s)
- Volker Koch
- Department of Marine Biology, Universidad Autónoma de Baja California Sur, La Paz, Baja California Sur, Mexico.
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