1
|
Rojas-Bracho L, Taylor B, Booth C, Thomas L, Jaramillo-Legorreta A, Nieto-García E, Cárdenas Hinojosa G, Barlow J, Mesnick SL, Gerrodette T, Olson P, Henry A, Rizo H, Hidalgo-Pla E, Bonilla-Garzón A. More vaquita porpoises survive than expected. ENDANGER SPECIES RES 2022. [DOI: 10.3354/esr01197] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/28/2023] Open
Abstract
In 2018, it was estimated that fewer than 20 of Mexico’s endemic vaquita porpoise Phocoena sinus remained, and the species was declining by 47% yr-1. Entanglement in gillnets is the sole threat to the species, and since the last population size estimate, gillnetting has increased in the small area where most vaquitas remain—a 12 × 24 km area in the Gulf of California near San Felipe, Mexico. We conducted research efforts in 2019 and 2021 in that area to estimate the minimum numbers of adults and calves and look for any signs that vaquitas are unhealthy. Through expert elicitation, we estimated between 7 and 15 unique individuals were seen in 2019 and 5-13 were seen in 2021. Calves were seen in both years, and all vaquitas appeared healthy. Population projections from the last full survey indicated that more vaquitas have survived than expected. We suggest that these surviving adult vaquitas may have learned to avoid entanglement in gillnets. These vaquitas and their calves provide hope that the species can survive. However, given the high levels of illegal gillnetting and the theft of equipment which hindered our monitoring efforts, and with only around 10 individuals remaining, survival can only be assured if vaquita habitat is made gillnet-free.
Collapse
Affiliation(s)
- L Rojas-Bracho
- PNUD/Sinergiaen en la Comisión Nacional de Áreas Naturales Protegidas, Ensenada, BC, México
| | - B Taylor
- Southwest Fisheries Science Center, National Marine Fisheries Service, National Oceanic and Atmospheric Administration, La Jolla, CA 92037, USA
| | - C Booth
- SMRU Consulting, St Andrews, Fife KY16 8LB, UK
| | - L Thomas
- Centre for Research into Ecological and Environmental Modelling, University of St Andrews, St Andrews, Fife KY16 9LZ, UK
| | | | - E Nieto-García
- Comisión Natural de Áreas Naturales Protegidas, Ensenada, BC, México
| | | | - J Barlow
- Southwest Fisheries Science Center, National Marine Fisheries Service, National Oceanic and Atmospheric Administration, La Jolla, CA 92037, USA
| | - SL Mesnick
- Southwest Fisheries Science Center, National Marine Fisheries Service, National Oceanic and Atmospheric Administration, La Jolla, CA 92037, USA
| | - T Gerrodette
- Southwest Fisheries Science Center, National Marine Fisheries Service, National Oceanic and Atmospheric Administration, La Jolla, CA 92037, USA
| | - P Olson
- Southwest Fisheries Science Center, National Marine Fisheries Service, National Oceanic and Atmospheric Administration, La Jolla, CA 92037, USA
| | - A Henry
- Southwest Fisheries Science Center, National Marine Fisheries Service, National Oceanic and Atmospheric Administration, La Jolla, CA 92037, USA
| | - H Rizo
- Museo de la Ballena y Ciencias del Mar, La Paz, BC 23000, México
| | - E Hidalgo-Pla
- Scripps Institution of Oceanography, University of California, San Diego, La Jolla, CA 92037, USA
| | - A Bonilla-Garzón
- K. Lisa Yang Center for Conservation Bioacoustics, Ithaca, NY 14850, USA
| |
Collapse
|
2
|
Foote AD, Hooper R, Alexander A, Baird RW, Baker CS, Ballance L, Barlow J, Brownlow A, Collins T, Constantine R, Dalla Rosa L, Davison NJ, Durban JW, Esteban R, Excoffier L, Martin SLF, Forney KA, Gerrodette T, Gilbert MTP, Guinet C, Hanson MB, Li S, Martin MD, Robertson KM, Samarra FIP, de Stephanis R, Tavares SB, Tixier P, Totterdell JA, Wade P, Wolf JBW, Fan G, Zhang Y, Morin PA. Runs of homozygosity in killer whale genomes provide a global record of demographic histories. Mol Ecol 2021; 30:6162-6177. [PMID: 34416064 DOI: 10.1111/mec.16137] [Citation(s) in RCA: 25] [Impact Index Per Article: 8.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/12/2021] [Revised: 08/10/2021] [Accepted: 08/18/2021] [Indexed: 02/06/2023]
Abstract
Runs of homozygosity (ROH) occur when offspring inherit haplotypes that are identical by descent from each parent. Length distributions of ROH are informative about population history; specifically, the probability of inbreeding mediated by mating system and/or population demography. Here, we investigated whether variation in killer whale (Orcinus orca) demographic history is reflected in genome-wide heterozygosity and ROH length distributions, using a global data set of 26 genomes representative of geographic and ecotypic variation in this species, and two F1 admixed individuals with Pacific-Atlantic parentage. We first reconstructed demographic history for each population as changes in effective population size through time using the pairwise sequential Markovian coalescent (PSMC) method. We found a subset of populations declined in effective population size during the Late Pleistocene, while others had more stable demography. Genomes inferred to have undergone ancestral declines in effective population size, were autozygous at hundreds of short ROH (<1 Mb), reflecting high background relatedness due to coalescence of haplotypes deep within the pedigree. In contrast, longer and therefore younger ROH (>1.5 Mb) were found in low latitude populations, and populations of known conservation concern. These include a Scottish killer whale, for which 37.8% of the autosomes were comprised of ROH >1.5 Mb in length. The fate of this population, in which only two adult males have been sighted in the past five years, and zero fecundity over the last two decades, may be inextricably linked to its demographic history and consequential inbreeding depression.
Collapse
Affiliation(s)
- Andrew D Foote
- Department of Natural History, NTNU University Museum, Norwegian University of Science and Technology (NTNU, Trondheim, Norway.,Molecular Ecology and Fisheries Genetics Laboratory, School of Biological Sciences, Bangor University, Bangor, Gwynedd, UK.,CMPG, Institute of Ecology and Evolution, University of Bern, Bern, Switzerland
| | - Rebecca Hooper
- University of Exeter, Penryn Campus, Penryn, Cornwall, UK
| | - Alana Alexander
- Department of Anatomy, School of Biomedical Sciences, University of Otago, Dunedin, New Zealand
| | | | - Charles Scott Baker
- Marine Mammal Institute, Oregon State University, Newport, Oregon, USA.,School of Biological Sciences, University of Auckland, Auckland, New Zealand
| | - Lisa Ballance
- Marine Mammal Institute, Oregon State University, Newport, Oregon, USA.,Marine Mammal and Turtle Division, Southwest Fisheries Science Center, National Marine Fisheries Service, National Oceanographic and Atmospheric Administration, La Jolla, California, USA
| | - Jay Barlow
- Marine Mammal and Turtle Division, Southwest Fisheries Science Center, National Marine Fisheries Service, National Oceanographic and Atmospheric Administration, La Jolla, California, USA
| | - Andrew Brownlow
- Scottish Marine Animal Stranding Scheme, Institute of Biodiversity, Animal Health & Comparative Medicine, College of Medical, Veterinary & Life Sciences, University of Glasgow, Glasgow, UK
| | - Tim Collins
- Ocean Giants Program, Wildlife Conservation Society, New York City, New York
| | | | - Luciano Dalla Rosa
- Laboratório de Ecologia e Conservação da Megafauna Marinha, Instituto de Oceanografia, Universidade Federal do Rio Grande, Rio Grande, Brazil
| | - Nicholas J Davison
- Scottish Marine Animal Stranding Scheme, Institute of Biodiversity, Animal Health & Comparative Medicine, College of Medical, Veterinary & Life Sciences, University of Glasgow, Glasgow, UK
| | - John W Durban
- Marine Mammal Institute, Oregon State University, Newport, Oregon, USA.,Marine Mammal and Turtle Division, Southwest Fisheries Science Center, National Marine Fisheries Service, National Oceanographic and Atmospheric Administration, La Jolla, California, USA
| | - Ruth Esteban
- CIRCE, Conservation, Information and Research on Cetaceans, Algeciras, Spain
| | - Laurent Excoffier
- CMPG, Institute of Ecology and Evolution, University of Bern, Bern, Switzerland
| | - Sarah L Fordyce Martin
- Department of Natural History, NTNU University Museum, Norwegian University of Science and Technology (NTNU, Trondheim, Norway
| | - Karin A Forney
- Marine Mammal and Turtle Division, Southwest Fisheries Science Center, National Marine Fisheries Service, National Oceanic and Atmospheric Administration, Moss Landing, California, USA.,Moss Landing Marine Laboratories, San Jose State University, Moss Landing, California, USA
| | - Tim Gerrodette
- Marine Mammal and Turtle Division, Southwest Fisheries Science Center, National Marine Fisheries Service, National Oceanographic and Atmospheric Administration, La Jolla, California, USA
| | - M Thomas P Gilbert
- Department of Natural History, NTNU University Museum, Norwegian University of Science and Technology (NTNU, Trondheim, Norway.,Section for Evolutionary Genomics, The GLOBE Institute, University of Copenhagen, Copenhagen, Denmark
| | - Christophe Guinet
- UMR 7372 La Rochelle Université - CNRS, Centre d'Etudes Biologiques de Chizé (CEBC), Villiers-en-Bois, France
| | - M Bradley Hanson
- National Marine Fisheries Service, National Oceanic and Atmospheric Administration, Northwest Fisheries Science Center, Seattle, Washington, USA
| | - Songhai Li
- Marine Mammal and Marine Bioacoustics Laboratory, Institute of Deep-Sea Science and Engineering, Chinese Academy of Science, Sanya, China
| | - Michael D Martin
- Department of Natural History, NTNU University Museum, Norwegian University of Science and Technology (NTNU, Trondheim, Norway
| | - Kelly M Robertson
- Marine Mammal and Turtle Division, Southwest Fisheries Science Center, National Marine Fisheries Service, National Oceanographic and Atmospheric Administration, La Jolla, California, USA
| | - Filipa I P Samarra
- University of Iceland's Institute of Research Centres, Vestmannaeyjar, Iceland
| | - Renaud de Stephanis
- CIRCE, Conservation, Information and Research on Cetaceans, Algeciras, Spain
| | - Sara B Tavares
- Scottish Oceans Institute, East Sands, University of St. Andrews, St. Andrews, UK.,Cetacean Research Program, Pacific Biological Station, Fisheries and Oceans Canada, Nanaimo, Canada
| | - Paul Tixier
- UMR 7372 La Rochelle Université - CNRS, Centre d'Etudes Biologiques de Chizé (CEBC), Villiers-en-Bois, France.,MARBEC Université de Montpellier-CNRS-IFREMER-IRD, Sète, France
| | | | - Paul Wade
- National Marine Mammal Laboratory, National Marine Fisheries Service, National Oceanic and Atmospheric Administration, Alaska Fisheries Science Center, Seattle, Washington, USA
| | - Jochen B W Wolf
- Section of Evolutionary Biology, Department of Biology II, Ludwig Maximilian University of Munich, Planegg-Martinsried, Germany
| | - Guangyi Fan
- BGI-Qingdao, BGI-Shenzhen, Qingdao, China.,BGI-Shenzhen, Shenzhen, China.,China National GeneBank, BGI-Shenzhen, Shenzhen, China
| | - Yaolei Zhang
- BGI-Qingdao, BGI-Shenzhen, Qingdao, China.,Translational Immunology group, Department of Biotechnology and Biomedicine, Technical University of Denmark, Lyngby, Denmark
| | - Phillip A Morin
- Marine Mammal and Turtle Division, Southwest Fisheries Science Center, National Marine Fisheries Service, National Oceanographic and Atmospheric Administration, La Jolla, California, USA
| |
Collapse
|
3
|
Ruiz‐Cooley RI, Gerrodette T, Chivers SJ, Danil K. Cooperative feeding in common dolphins as suggested by ontogenetic patterns in δ
15
N bulk and amino acids. J Anim Ecol 2021; 90:1583-1595. [DOI: 10.1111/1365-2656.13478] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/24/2020] [Accepted: 03/09/2021] [Indexed: 01/08/2023]
Affiliation(s)
- Rocio I. Ruiz‐Cooley
- Departamento de Oceanografía Biológica Centro de Investigación Científica y de Educación Superior de Ensenada Ensenada Baja California México
- Moss Landing Marine Laboratories San Jose State University Moss Landing CA USA
| | - Tim Gerrodette
- Southwest Fisheries Science Center National Marine Fisheries ServiceNational Oceanic and Atmospheric Administration Fisheries La Jolla CA USA
| | - Susan J. Chivers
- Southwest Fisheries Science Center National Marine Fisheries ServiceNational Oceanic and Atmospheric Administration Fisheries La Jolla CA USA
| | - Kerri Danil
- Southwest Fisheries Science Center National Marine Fisheries ServiceNational Oceanic and Atmospheric Administration Fisheries La Jolla CA USA
| |
Collapse
|
4
|
Cárdenas Hinojosa G, de la Cueva H, Gerrodette T, Jaramillo-Legorreta AM. Distribution of the acoustic occurrence of dolphins during the summers 2011 to 2015 in the Upper Gulf of California, Mexico. PeerJ 2020; 8:e9121. [PMID: 32509451 PMCID: PMC7245336 DOI: 10.7717/peerj.9121] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/26/2019] [Accepted: 04/13/2020] [Indexed: 11/20/2022] Open
Abstract
Baseline knowledge of spatial and temporal distribution patterns is essential for cetacean management and conservation. Such knowledge is particularly important in areas where gillnet fishing occurs, as the Upper Gulf of California, which increases the probability of bycatch of cetaceans. In this area, the vaquita porpoise (Phocoena sinus) has been widely studied, but the knowledge of other cetaceans is scarce and based on traditional visual survey methods. We used data collected by an array of acoustic click detectors (C-PODs) during the summers 2011 to 2015 to analyze the distribution of dolphins in the Vaquita Refuge in the Upper Gulf of California. We recorded 120,038 echolocation click trains of dolphins during 12,371 days of recording effort at 46 sampling sites. Based on simultaneous visual and acoustic data, we estimated a false positive acoustic detection rate of 19.4%. Dolphin acoustic activity varied among sites, with higher activity in the east of the Vaquita Refuge. Acoustic activity was higher at night than during the day. We used negative binomial generalized linear models to study the count of clicks of dolphins in relation to spatial, temporal, physical, biological and anthropogenic explanatory variables. The best model selected for the response variable included sampling site, day-night condition, and vertical component of tide speed. Patterns in the spatial distribution of predicted acoustic activity of dolphins were similar to the acoustic activity observed per sampling season. Higher acoustic activity was predicted at night, but the tide speed variable was not relevant under this condition. Acoustic activity patterns could be related to the availability of prey resources since echolocation click trains are associated with foraging activities of dolphins. This is the first study of the distribution of dolphins in Mexico using medium-term systematic passive acoustic monitoring, and the results can contribute to better management to the natural protected area located in the Upper Gulf of California.
Collapse
Affiliation(s)
- Gustavo Cárdenas Hinojosa
- Departamento de Biología de la Conservación, Centro de Investigación Científica y de Educación Superior de Ensenada, Ensenada, Baja California, México.,Comisión Nacional de Áreas Naturales Protegidas, Secretaría de Medio Ambiente y Recursos Naturales, Ensenada, Baja California, México
| | - Horacio de la Cueva
- Departamento de Biología de la Conservación, Centro de Investigación Científica y de Educación Superior de Ensenada, Ensenada, Baja California, México
| | - Tim Gerrodette
- Southwest Fisheries Science Center, National Oceanic and Atmospheric Administration, San Diego, CA, United States of America
| | - Armando M Jaramillo-Legorreta
- Comisión Nacional de Áreas Naturales Protegidas, Secretaría de Medio Ambiente y Recursos Naturales, Ensenada, Baja California, México
| |
Collapse
|
5
|
Affiliation(s)
- R. Glennie
- School of Mathematics and Statistics, Centre for Research into Ecological and Environmental Modelling, University of St Andrews, St Andrews, UK
| | - S. T. Buckland
- School of Mathematics and Statistics, Centre for Research into Ecological and Environmental Modelling, University of St Andrews, St Andrews, UK
| | - R. Langrock
- Department of Business Administration and Economics, Bielefeld University, Bielefeld, Germany
| | - T. Gerrodette
- Southwest Fisheries Science Centre, NOAA Fisheries, La Jolla, CA
| | - L. T. Ballance
- Southwest Fisheries Science Centre, NOAA Fisheries, La Jolla, CA
| | - S. J. Chivers
- Southwest Fisheries Science Centre, NOAA Fisheries, La Jolla, CA
| | - M. D. Scott
- Inter-American Tropical Tuna Commission, California, La Jolla, CA
| |
Collapse
|
6
|
Foote AD, Martin MD, Louis M, Pacheco G, Robertson KM, Sinding MHS, Amaral AR, Baird RW, Baker CS, Ballance L, Barlow J, Brownlow A, Collins T, Constantine R, Dabin W, Dalla Rosa L, Davison NJ, Durban JW, Esteban R, Ferguson SH, Gerrodette T, Guinet C, Hanson MB, Hoggard W, Matthews CJD, Samarra FIP, de Stephanis R, Tavares SB, Tixier P, Totterdell JA, Wade P, Excoffier L, Gilbert MTP, Wolf JBW, Morin PA. Killer whale genomes reveal a complex history of recurrent admixture and vicariance. Mol Ecol 2019; 28:3427-3444. [PMID: 31131963 DOI: 10.1111/mec.15099] [Citation(s) in RCA: 24] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/14/2019] [Revised: 04/06/2019] [Accepted: 04/08/2019] [Indexed: 02/06/2023]
Abstract
Reconstruction of the demographic and evolutionary history of populations assuming a consensus tree-like relationship can mask more complex scenarios, which are prevalent in nature. An emerging genomic toolset, which has been most comprehensively harnessed in the reconstruction of human evolutionary history, enables molecular ecologists to elucidate complex population histories. Killer whales have limited extrinsic barriers to dispersal and have radiated globally, and are therefore a good candidate model for the application of such tools. Here, we analyse a global data set of killer whale genomes in a rare attempt to elucidate global population structure in a nonhuman species. We identify a pattern of genetic homogenisation at lower latitudes and the greatest differentiation at high latitudes, even between currently sympatric lineages. The processes underlying the major axis of structure include high drift at the edge of species' range, likely associated with founder effects and allelic surfing during postglacial range expansion. Divergence between Antarctic and non-Antarctic lineages is further driven by ancestry segments with up to four-fold older coalescence time than the genome-wide average; relicts of a previous vicariance during an earlier glacial cycle. Our study further underpins that episodic gene flow is ubiquitous in natural populations, and can occur across great distances and after substantial periods of isolation between populations. Thus, understanding the evolutionary history of a species requires comprehensive geographic sampling and genome-wide data to sample the variation in ancestry within individuals.
Collapse
Affiliation(s)
- Andrew D Foote
- CMPG, Institute of Ecology and Evolution, University of Bern, Bern, Switzerland
| | | | - Marie Louis
- Department of Biology, Section for Evolutionary Genomics, University of Copenhagen, Copenhagen, Denmark.,Scottish Oceans Institute, East Sands, University of St. Andrews, St. Andrews, UK
| | - George Pacheco
- Department of Biology, Section for Evolutionary Genomics, University of Copenhagen, Copenhagen, Denmark
| | - Kelly M Robertson
- Marine Mammal and Turtle Division, National Marine Fisheries Service, National Oceanographic and Atmospheric Administration, Southwest Fisheries Science Center, La Jolla, California
| | - Mikkel-Holger S Sinding
- Department of Biology, Section for Evolutionary Genomics, University of Copenhagen, Copenhagen, Denmark.,Greenland Institute of Natural Resources, Nuuk, Greenland
| | - Ana R Amaral
- American Museum of Natural History, New York City, New York.,Faculdade de Ciências Universidade de Lisboa, Centre for Ecology, Evolution and Environmental Changes, Lisboa, Portugal
| | | | - Charles Scott Baker
- Department of Fisheries and Wildlife, Marine Mammal Institute, Oregon State University, Newport, Oregon.,School of Biological Sciences, University of Auckland, Auckland, New Zealand
| | - Lisa Ballance
- Marine Mammal and Turtle Division, National Marine Fisheries Service, National Oceanographic and Atmospheric Administration, Southwest Fisheries Science Center, La Jolla, California
| | - Jay Barlow
- Marine Mammal and Turtle Division, National Marine Fisheries Service, National Oceanographic and Atmospheric Administration, Southwest Fisheries Science Center, La Jolla, California
| | - Andrew Brownlow
- Scottish Marine Animal Stranding Scheme, SRUC Veterinary Services Drummondhill, Inverness, UK
| | - Tim Collins
- Ocean Giants Program, Wildlife Conservation Society, New York City, New York
| | | | - Willy Dabin
- Observatoire Pelagis, Université de La Rochelle-CNRS, La Rochelle, France
| | - Luciano Dalla Rosa
- Laboratório de Ecologia e Conservação da Megafauna Marinha, Instituto de Oceanografia, Universidade Federal do Rio Grande, Rio Grande, Brazil
| | - Nicholas J Davison
- Scottish Marine Animal Stranding Scheme, SRUC Veterinary Services Drummondhill, Inverness, UK
| | - John W Durban
- Marine Mammal and Turtle Division, National Marine Fisheries Service, National Oceanographic and Atmospheric Administration, Southwest Fisheries Science Center, La Jolla, California
| | - Ruth Esteban
- CIRCE, Conservation, Information and Research on Cetaceans, Algeciras, Spain
| | | | - Tim Gerrodette
- Marine Mammal and Turtle Division, National Marine Fisheries Service, National Oceanographic and Atmospheric Administration, Southwest Fisheries Science Center, La Jolla, California
| | - Christophe Guinet
- Centre d'Etudes Biologiques de Chizé (CEBC), CNRS-ULR, UMR, Chizé, France
| | - M Bradley Hanson
- National Marine Fisheries Service, National Oceanic and Atmospheric Administration, Northwest Fisheries Science Center, Seattle, Washington
| | - Wayne Hoggard
- National Marine Fisheries Service, NOAA, Southeast Fisheries Science Center, Pascagoula, Mississippi
| | | | | | - Renaud de Stephanis
- CIRCE, Conservation, Information and Research on Cetaceans, Algeciras, Spain
| | - Sara B Tavares
- Scottish Oceans Institute, East Sands, University of St. Andrews, St. Andrews, UK
| | - Paul Tixier
- Centre d'Etudes Biologiques de Chizé (CEBC), CNRS-ULR, UMR, Chizé, France.,School of Life and Environmental Sciences (Burwood Campus), Deakin University, Geelong, Victoria, Australia
| | - John A Totterdell
- Marine Information and Research Group-Australia (MIRG), Quinns Rocks, Western Australia, Australia
| | - Paul Wade
- National Marine Mammal Laboratory, National Marine Fisheries Service, National Oceanic and Atmospheric Administration, Alaska Fisheries Science Center, Seattle, Washington
| | - Laurent Excoffier
- CMPG, Institute of Ecology and Evolution, University of Bern, Bern, Switzerland
| | - M Thomas P Gilbert
- NTNU University Museum, Trondheim, Norway.,Department of Biology, Section for Evolutionary Genomics, University of Copenhagen, Copenhagen, Denmark
| | - Jochen B W Wolf
- Division of Evolutionary Biology, Faculty of Biology, LMU Munich, Planegg-Martinsried, Germany.,Department of Evolutionary Biology, Science of Life Laboratory, Uppsala University, Uppsala, Sweden
| | - Phillip A Morin
- Marine Mammal and Turtle Division, National Marine Fisheries Service, National Oceanographic and Atmospheric Administration, Southwest Fisheries Science Center, La Jolla, California
| |
Collapse
|
7
|
Yuan Y, Bachl FE, Lindgren F, Borchers DL, Illian JB, Buckland ST, Rue H, Gerrodette T. Point process models for spatio-temporal distance sampling data from a large-scale survey of blue whales. Ann Appl Stat 2017. [DOI: 10.1214/17-aoas1078] [Citation(s) in RCA: 51] [Impact Index Per Article: 7.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
|
8
|
Boyd C, Barlow J, Becker EA, Forney KA, Gerrodette T, Moore JE, Punt AE. Estimation of population size and trends for highly mobile species with dynamic spatial distributions. DIVERS DISTRIB 2017. [DOI: 10.1111/ddi.12663] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022] Open
Affiliation(s)
- Charlotte Boyd
- School of Aquatic and Fishery Sciences; University of Washington; Seattle WA USA
- Southwest Fisheries Science Center; National Marine Fisheries Service; National Oceanic and Atmospheric Administration; La Jolla CA USA
| | - Jay Barlow
- Southwest Fisheries Science Center; National Marine Fisheries Service; National Oceanic and Atmospheric Administration; La Jolla CA USA
| | - Elizabeth A. Becker
- Marine Mammal and Turtle Division; Southwest Fisheries Science Center; National Marine Fisheries Service; National Oceanic and Atmospheric Administration; Moss Landing CA 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
| | - Tim Gerrodette
- Southwest Fisheries Science Center; National Marine Fisheries Service; National Oceanic and Atmospheric Administration; La Jolla CA USA
| | - Jeffrey E. Moore
- Southwest Fisheries Science Center; National Marine Fisheries Service; National Oceanic and Atmospheric Administration; La Jolla CA USA
| | - André E. Punt
- School of Aquatic and Fishery Sciences; University of Washington; Seattle WA USA
| |
Collapse
|
9
|
Ruiz-Cooley RI, Gerrodette T, Fiedler PC, Chivers SJ, Danil K, Ballance LT. Temporal variation in pelagic food chain length in response to environmental change. Sci Adv 2017; 3:e1701140. [PMID: 29057322 PMCID: PMC5647130 DOI: 10.1126/sciadv.1701140] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/03/2017] [Accepted: 09/20/2017] [Indexed: 05/31/2023]
Abstract
Climate variability alters nitrogen cycling, primary productivity, and dissolved oxygen concentration in marine ecosystems. We examined the role of this variability (as measured by six variables) on food chain length (FCL) in the California Current (CC) by reconstructing a time series of amino acid-specific δ15N values derived from common dolphins, an apex pelagic predator, and using two FCL proxies. Strong declines in FCL were observed after the 1997-1999 El Niño Southern Oscillation (ENSO) event. Bayesian models revealed longer FCLs under intermediate conditions for surface temperature, chlorophyll concentration, multivariate ENSO index, and total plankton volume but not for hypoxic depth and nitrate concentration. Our results challenge the prevalent paradigm that suggested long-term stability in the food web structure in the CC and, instead, reveal that pelagic food webs respond strongly to disturbances associated with ENSO events, local oceanography, and ongoing changes in climate.
Collapse
Affiliation(s)
- Rocio I. Ruiz-Cooley
- Moss Landing Marine Laboratories, San Jose State University, Moss Landing, CA 95039, USA
- Southwest Fisheries Science Center, National Oceanic and Atmospheric Administration Fisheries Service, La Jolla, CA 92037, USA
| | - Tim Gerrodette
- Southwest Fisheries Science Center, National Oceanic and Atmospheric Administration Fisheries Service, La Jolla, CA 92037, USA
| | - Paul C. Fiedler
- Southwest Fisheries Science Center, National Oceanic and Atmospheric Administration Fisheries Service, La Jolla, CA 92037, USA
| | - Susan J. Chivers
- Southwest Fisheries Science Center, National Oceanic and Atmospheric Administration Fisheries Service, La Jolla, CA 92037, USA
| | - Kerri Danil
- Southwest Fisheries Science Center, National Oceanic and Atmospheric Administration Fisheries Service, La Jolla, CA 92037, USA
| | - Lisa T. Ballance
- Southwest Fisheries Science Center, National Oceanic and Atmospheric Administration Fisheries Service, La Jolla, CA 92037, USA
- Scripps Institution of Oceanography, University of California San Diego, La Jolla, CA 92037, USA
| |
Collapse
|
10
|
Jaramillo-Legorreta A, Cardenas-Hinojosa G, Nieto-Garcia E, Rojas-Bracho L, Ver Hoef J, Moore J, Tregenza N, Barlow J, Gerrodette T, Thomas L, Taylor B. Passive acoustic monitoring of the decline of Mexico's critically endangered vaquita. Conserv Biol 2017; 31:183-191. [PMID: 27338145 DOI: 10.1111/cobi.12789] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/21/2016] [Revised: 06/03/2016] [Accepted: 06/17/2016] [Indexed: 06/06/2023]
Abstract
The vaquita (Phocoena sinus) is the world's most endangered marine mammal with approximately 245 individuals remaining in 2008. This species of porpoise is endemic to the northern Gulf of California, Mexico, and historically the population has declined because of unsustainable bycatch in gillnets. An illegal gillnet fishery for an endangered fish, the totoaba (Totoaba macdonaldi), has recently resurged throughout the vaquita's range. The secretive but lucrative wildlife trade with China for totoaba swim bladders has probably increased vaquita bycatch mortality by an unknown amount. Precise population monitoring by visual surveys is difficult because vaquitas are inherently hard to see and have now become so rare that sighting rates are very low. However, their echolocation clicks can be identified readily on specialized acoustic detectors. Acoustic detections on an array of 46 moored detectors indicated vaquita acoustic activity declined by 80% between 2011 and 2015 in the central part of the species' range. Statistical models estimated an annual rate of decline of 34% (95% Bayesian credible interval -48% to -21%). Based on results from 2011 to 2014, the government of Mexico enacted and is enforcing an emergency 2-year ban on gillnets throughout the species' range to prevent extinction, at a cost of US$74 million to compensate fishers. Developing precise acoustic monitoring methods proved critical to exposing the severity of vaquitas' decline and emphasizes the need for continual monitoring to effectively manage critically endangered species.
Collapse
Affiliation(s)
- Armando Jaramillo-Legorreta
- Instituto Nacional de Ecología y Cambio Climático/SEMARNAT, Coordinación de Investigación y Conservación de Mamíferos Marinos, CICESE Camper 10, Carretera Ensenada-Tijuana 3918, Zona Playitas, Ensenada, B.C, 22860, México
| | - Gustavo Cardenas-Hinojosa
- Instituto Nacional de Ecología y Cambio Climático/SEMARNAT, Coordinación de Investigación y Conservación de Mamíferos Marinos, CICESE Camper 10, Carretera Ensenada-Tijuana 3918, Zona Playitas, Ensenada, B.C, 22860, México
- Departamento de Biología de la Conservación, Centro de Investigación Científica y Educación Superior de Ensenada, Carretera Ensenada-Tijuana 3918, Zona Playitas, Ensenada, Baja California, CP 22860, México
| | - Edwyna Nieto-Garcia
- Instituto Nacional de Ecología y Cambio Climático/SEMARNAT, Coordinación de Investigación y Conservación de Mamíferos Marinos, CICESE Camper 10, Carretera Ensenada-Tijuana 3918, Zona Playitas, Ensenada, B.C, 22860, México
| | - Lorenzo Rojas-Bracho
- Instituto Nacional de Ecología y Cambio Climático/SEMARNAT, Coordinación de Investigación y Conservación de Mamíferos Marinos, CICESE Camper 10, Carretera Ensenada-Tijuana 3918, Zona Playitas, Ensenada, B.C, 22860, México
| | - Jay Ver Hoef
- Alaska Fisheries Science Center, NOAA Fisheries, National Marine Mammal Laboratory, 7600 Sand Point Way N.E., Building 4, Seattle, WA, 98115, U.S.A
| | - Jeffrey Moore
- Southwest Fisheries Science Center, NOAA Fisheries, Protected Resources Division, 8901 La Jolla Shores Dr, La Jolla, CA, 92037, U.S.A
| | | | - Jay Barlow
- Southwest Fisheries Science Center, NOAA Fisheries, Protected Resources Division, 8901 La Jolla Shores Dr, La Jolla, CA, 92037, U.S.A
| | - Tim Gerrodette
- Southwest Fisheries Science Center, NOAA Fisheries, Protected Resources Division, 8901 La Jolla Shores Dr, La Jolla, CA, 92037, U.S.A
| | - Len Thomas
- University of St Andrews, Centre for Research into Ecological and Environmental Modelling, The Observatory, Buchanan Gardens, St Andrews, Fife KY16 9LZ, U.K
| | - Barbara Taylor
- Southwest Fisheries Science Center, NOAA Fisheries, Protected Resources Division, 8901 La Jolla Shores Dr, La Jolla, CA, 92037, U.S.A
| |
Collapse
|
11
|
Taylor BL, Rojas-Bracho L, Moore J, Jaramillo-Legorreta A, Ver Hoef JM, Cardenas-Hinojosa G, Nieto-Garcia E, Barlow J, Gerrodette T, Tregenza N, Thomas L, Hammond PS. Extinction is Imminent for Mexico's Endemic Porpoise Unless Fishery Bycatch is Eliminated. Conserv Lett 2016. [DOI: 10.1111/conl.12331] [Citation(s) in RCA: 61] [Impact Index Per Article: 7.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022] Open
Affiliation(s)
- Barbara L. Taylor
- Southwest Fisheries Science Center, NOAA Fisheries; Marine Mammal and Turtle Division; 8901 La Jolla Shores Dr. La Jolla CA 92037 USA
| | - Lorenzo Rojas-Bracho
- Instituto Nacional de Ecologia y Cambio Climatico/SEMARNAT; Coordinacion de Investigacion y Conservacion de Mamiferos Marinos; CICESE Camper 10, Carretera Ensenada-Tijuana 3918, Zona Playitas Ensenada B.C. 22860 Mexico
| | - Jeffrey Moore
- Southwest Fisheries Science Center, NOAA Fisheries; Marine Mammal and Turtle Division; 8901 La Jolla Shores Dr. La Jolla CA 92037 USA
| | - Armando Jaramillo-Legorreta
- Instituto Nacional de Ecologia y Cambio Climatico/SEMARNAT; Coordinacion de Investigacion y Conservacion de Mamiferos Marinos; CICESE Camper 10, Carretera Ensenada-Tijuana 3918, Zona Playitas Ensenada B.C. 22860 Mexico
| | - Jay M. Ver Hoef
- Alaska Fisheries Science Center, NOAA Fisheries; Marine Mammal Laboratory; 7600 Sand Point Way N.E. Seattle WA 98115 USA
| | - Gustavo Cardenas-Hinojosa
- Instituto Nacional de Ecologia y Cambio Climatico/SEMARNAT; Coordinacion de Investigacion y Conservacion de Mamiferos Marinos; CICESE Camper 10, Carretera Ensenada-Tijuana 3918, Zona Playitas Ensenada B.C. 22860 Mexico
| | - Edwyna Nieto-Garcia
- Instituto Nacional de Ecologia y Cambio Climatico/SEMARNAT; Coordinacion de Investigacion y Conservacion de Mamiferos Marinos; CICESE Camper 10, Carretera Ensenada-Tijuana 3918, Zona Playitas Ensenada B.C. 22860 Mexico
| | - Jay Barlow
- Southwest Fisheries Science Center, NOAA Fisheries; Marine Mammal and Turtle Division; 8901 La Jolla Shores Dr. La Jolla CA 92037 USA
| | - Tim Gerrodette
- Southwest Fisheries Science Center, NOAA Fisheries; Marine Mammal and Turtle Division; 8901 La Jolla Shores Dr. La Jolla CA 92037 USA
| | | | - Len Thomas
- University of St Andrews, Centre for Research into Ecological and Environmental Modelling; The Observatory; Buchanan Gardens, St Andrews KY16 9LZ Fife
| | - Philip S. Hammond
- University of St Andrews, Sea Mammal Research Unit; Scottish Oceans Institute; St Andrews KY16 8LB Fife
| |
Collapse
|
12
|
McClatchie S, Field J, Thompson AR, Gerrodette T, Lowry M, Fiedler PC, Watson W, Nieto KM, Vetter RD. Correction to 'Food limitation of sea lion pups and the decline of forage off central and southern California'. R Soc Open Sci 2016; 3:160192. [PMID: 27152229 PMCID: PMC4852652 DOI: 10.1098/rsos.160192] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Indexed: 06/05/2023]
Abstract
[This corrects the article DOI: 10.1098/rsos.150628.].
Collapse
|
13
|
McClatchie S, Field J, Thompson AR, Gerrodette T, Lowry M, Fiedler PC, Watson W, Nieto KM, Vetter RD. Food limitation of sea lion pups and the decline of forage off central and southern California. R Soc Open Sci 2016; 3:150628. [PMID: 27069651 PMCID: PMC4821262 DOI: 10.1098/rsos.150628] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/16/2015] [Accepted: 02/02/2016] [Indexed: 05/18/2023]
Abstract
California sea lions increased from approximately 50 000 to 340 000 animals in the last 40 years, and their pups are starving and stranding on beaches in southern California, raising questions about the adequacy of their food supply. We investigated whether the declining sea lion pup weight at San Miguel rookery was associated with changes in abundance and quality of sardine, anchovy, rockfish and market squid forage. In the last decade off central California, where breeding female sea lions from San Miguel rookery feed, sardine and anchovy greatly decreased in biomass, whereas market squid and rockfish abundance increased. Pup weights fell as forage food quality declined associated with changes in the relative abundances of forage species. A model explained 67% of the variance in pup weights using forage from central and southern California and 81% of the variance in pup weights using forage from the female sea lion foraging range. A shift from high to poor quality forage for breeding females results in food limitation of the pups, ultimately flooding animal rescue centres with starving sea lion pups. Our study is unusual in using a long-term, fishery-independent dataset to directly address an important consequence of forage decline on the productivity of a large marine predator. Whether forage declines are environmentally driven, are due to a combination of environmental drivers and fishing removals, or are due to density-dependent interactions between forage and sea lions is uncertain. However, declining forage abundance and quality was coherent over a large area (32.5-38° N) for a decade, suggesting that trends in forage are environmentally driven.
Collapse
Affiliation(s)
- Sam McClatchie
- Fisheries Resources Division, Southwest Fisheries Science Center, NOAA Fisheries Service, 8901 La Jolla Shores Drive, La Jolla, CA 92037-1509, USA
- Author for correspondence: Sam McClatchie e-mail:
| | - John Field
- Fisheries Ecology Division, Southwest Fisheries Science Center, NOAA Fisheries Service, 110 Shaffer Road, Santa Cruz, CA 95062, USA
| | - Andrew R. Thompson
- Fisheries Resources Division, Southwest Fisheries Science Center, NOAA Fisheries Service, 8901 La Jolla Shores Drive, La Jolla, CA 92037-1509, USA
| | - Tim Gerrodette
- Marine Mammal and Turtle Division, Southwest Fisheries Science Center, NOAA Fisheries Service, 8901 La Jolla Shores Drive, La Jolla, CA 92037-1509, USA
| | - Mark Lowry
- Marine Mammal and Turtle Division, Southwest Fisheries Science Center, NOAA Fisheries Service, 8901 La Jolla Shores Drive, La Jolla, CA 92037-1509, USA
| | - Paul C. Fiedler
- Marine Mammal and Turtle Division, Southwest Fisheries Science Center, NOAA Fisheries Service, 8901 La Jolla Shores Drive, La Jolla, CA 92037-1509, USA
| | - William Watson
- Fisheries Resources Division, Southwest Fisheries Science Center, NOAA Fisheries Service, 8901 La Jolla Shores Drive, La Jolla, CA 92037-1509, USA
| | - Karen M. Nieto
- Water Resources Unit, Institute for Environment and Sustainability, European Commission Joint Research Centre, Ispra, Italy
| | - Russell D. Vetter
- Fisheries Resources Division, Southwest Fisheries Science Center, NOAA Fisheries Service, 8901 La Jolla Shores Drive, La Jolla, CA 92037-1509, USA
| |
Collapse
|
14
|
Pardo MA, Gerrodette T, Beier E, Gendron D, Forney KA, Chivers SJ, Barlow J, Palacios DM. Inferring cetacean population densities from the absolute dynamic topography of the ocean in a hierarchical Bayesian framework. PLoS One 2015; 10:e0120727. [PMID: 25785692 PMCID: PMC4364891 DOI: 10.1371/journal.pone.0120727] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/10/2014] [Accepted: 01/29/2015] [Indexed: 11/23/2022] Open
Abstract
We inferred the population densities of blue whales (Balaenoptera musculus) and short-beaked common dolphins (Delphinus delphis) in the Northeast Pacific Ocean as functions of the water-column’s physical structure by implementing hierarchical models in a Bayesian framework. This approach allowed us to propagate the uncertainty of the field observations into the inference of species-habitat relationships and to generate spatially explicit population density predictions with reduced effects of sampling heterogeneity. Our hypothesis was that the large-scale spatial distributions of these two cetacean species respond primarily to ecological processes resulting from shoaling and outcropping of the pycnocline in regions of wind-forced upwelling and eddy-like circulation. Physically, these processes affect the thermodynamic balance of the water column, decreasing its volume and thus the height of the absolute dynamic topography (ADT). Biologically, they lead to elevated primary productivity and persistent aggregation of low-trophic-level prey. Unlike other remotely sensed variables, ADT provides information about the structure of the entire water column and it is also routinely measured at high spatial-temporal resolution by satellite altimeters with uniform global coverage. Our models provide spatially explicit population density predictions for both species, even in areas where the pycnocline shoals but does not outcrop (e.g. the Costa Rica Dome and the North Equatorial Countercurrent thermocline ridge). Interannual variations in distribution during El Niño anomalies suggest that the population density of both species decreases dramatically in the Equatorial Cold Tongue and the Costa Rica Dome, and that their distributions retract to particular areas that remain productive, such as the more oceanic waters in the central California Current System, the northern Gulf of California, the North Equatorial Countercurrent thermocline ridge, and the more southern portion of the Humboldt Current System. We posit that such reductions in available foraging habitats during climatic disturbances could incur high energetic costs on these populations, ultimately affecting individual fitness and survival.
Collapse
Affiliation(s)
- Mario A. Pardo
- Posgrado en Ciencias del Mar y Limnología, Universidad Nacional Autónoma de México, Distrito Federal, 04510, Mexico
- Unidad La Paz, Centro de Investigación Científica y de Educación Superior de Ensenada, La Paz, Baja California Sur, 23050, Mexico
- * E-mail:
| | - Tim Gerrodette
- Marine Mammal and Turtle Division, Southwest Fisheries Science Center, National Marine Fisheries Service, National Oceanic and Atmospheric Administration, La Jolla, California, 92037-1508, United States of America
| | - Emilio Beier
- Unidad La Paz, Centro de Investigación Científica y de Educación Superior de Ensenada, La Paz, Baja California Sur, 23050, Mexico
| | - Diane Gendron
- Centro Interdisciplinario de Ciencias Marinas, Instituto Politécnico Nacional, La Paz, Baja California Sur, 23096, Mexico
| | - Karin A. Forney
- Marine Mammal and Turtle Division, Southwest Fisheries Science Center, National Marine Fisheries Service, National Oceanic and Atmospheric Administration, La Jolla, California, 92037-1508, United States of America
| | - Susan J. Chivers
- Marine Mammal and Turtle Division, Southwest Fisheries Science Center, National Marine Fisheries Service, National Oceanic and Atmospheric Administration, La Jolla, California, 92037-1508, United States of America
| | - Jay Barlow
- Marine Mammal and Turtle Division, Southwest Fisheries Science Center, National Marine Fisheries Service, National Oceanic and Atmospheric Administration, La Jolla, California, 92037-1508, United States of America
| | - Daniel M. Palacios
- Marine Mammal Institute, Oregon State University, Newport, Oregon, 97365, United States of America
| |
Collapse
|
15
|
Ruiz-Cooley RI, Gerrodette T. Tracking large-scale latitudinal patterns of δ13C and δ15N along the E Pacific using epi-mesopelagic squid as indicators. Ecosphere 2012. [DOI: 10.1890/es12-00094.1] [Citation(s) in RCA: 37] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
|
16
|
Gerrodette T, Olson R, Reilly S, Watters G, Perrin W. Ecological metrics of biomass removed by three methods of purse-seine fishing for tunas in the eastern tropical Pacific Ocean. Conserv Biol 2012; 26:248-256. [PMID: 22443130 DOI: 10.1111/j.1523-1739.2011.01817.x] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/31/2023]
Abstract
An ecosystem approach to fisheries management is a widely recognized goal, but describing and measuring the effects of a fishery on an ecosystem is difficult. Ecological information on the entire catch (all animals removed, whether retained or discarded) of both species targeted by the fishery and nontarget species (i.e., bycatch) is required. We used data from the well-documented purse-seine fishery for tunas (Thunnus albacares, T. obesus, and Katsuwonus pelamis) in the eastern tropical Pacific Ocean to examine the fishery's ecological effects. Purse-seine fishing in the eastern tropical Pacific is conducted in 3 ways that differ in the amount and composition of target species and bycatch. The choice of method depends on whether the tunas are swimming alone (unassociated sets), associated with dolphins (dolphin sets), or associated with floating objects (floating-object sets). Among the fishing methods, we compared catch on the basis of weight, number of individuals, trophic level, replacement time, and diversity. Floating-object sets removed 2-3 times as much biomass as the other 2 methods, depending on how removal was measured. Results of previous studies suggest the ecological effects of floating-object sets are thousands of times greater than the effects of other methods, but these results were derived from only numbers of discarded animals. Management of the fishery has been driven to a substantial extent by a focus on reducing bycatch, although discards are currently 4.8% of total catch by weight, compared with global averages of 7.5% for tuna longline fishing and 30.0% for midwater trawling. An ecosystem approach to fisheries management requires that ecological effects of fishing on all animals removed by a fishery, not just bycatch or discarded catch, be measured with a variety of metrics.
Collapse
Affiliation(s)
- Tim Gerrodette
- Southwest Fisheries Science Center, NMFS, NOAA, La Jolla, CA 92037, USA.
| | | | | | | | | |
Collapse
|
17
|
|
18
|
Johanos TC, Becker BL, Baker JD, Ragen TJ, Gilmartin WG, Gerrodette T. Impacts of sex ratio reduction on male aggression in the Critically Endangered Hawaiian monk seal Monachus schauinslandi. ENDANGER SPECIES RES 2010. [DOI: 10.3354/esr00259] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022] Open
|
19
|
|
20
|
Eguchi T, Gerrodette T, Pitman RL, Seminoff JA, Dutton PH. At-sea density and abundance estimates of the olive ridley turtle Lepidochelys olivacea in the eastern tropical Pacific. ENDANGER SPECIES RES 2007. [DOI: 10.3354/esr003191] [Citation(s) in RCA: 39] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022] Open
|
21
|
May-Collado L, Gerrodette T, Calambokidis J, Rasmussen K, Sereg I. Patterns of cetacean sighting distribution in the Pacific exclusive economic zone of Costa Rica based on data collected from 1979-2001. REV BIOL TROP 2005; 53:249-63. [PMID: 17354438] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 05/14/2023] Open
Abstract
Nineteen species of cetaceans (families Balaenopteridae, Kogiidae, Physeteridae, Ziphiidae and Delphinidae) occur in the Costa Rican Pacific Exclusive Economic Zone (EEZ). Based on data recorded from the EEZ by the Southwest Fisheries Service Center, Cascadia Research Collective, and CIMAR between 1979-2001, we mapped the distribution of 18 cetacean species. Our results suggest that the majority of the cetacean species use primarily oceanic waters, particularly those species within the families Balaenopteridae, Kogiidae. Physeteridae and Ziphiidae. Members of the family Delphinidae showed a wide variety of distribution patterns: seven species are widespread throughout the EEZ, four appear to be exclusively pelagic, and two are primarily coastal. Overall, three cetacean species appear to have populations concentrated in coastal waters: Stenella attenuata graffmani. Tursiops truncatus, and Megaptera novaeangliae. These three may be more susceptible to human activities due to the overlap of their ranges with fishery areas (tuna and artisanal fisheries), and an uncontrolled increase of touristic whale watching activities in several parts of their range. The distribution maps represent the first comprehensive representation of cetacean species that inhabit Costa Rican Pacific waters. They provide essential base-line information that may be used to initiate conservation and management efforts of the habitats where these animals reproduce and forage.
Collapse
Affiliation(s)
- Laura May-Collado
- CIMR, Ciudad de la Investigación, Universidad de Costa Rica, 2060 San José, Costa Rica.
| | | | | | | | | |
Collapse
|
22
|
|
23
|
|
24
|
Dayton PK, Currie V, Gerrodette T, Keller BD, Rosenthal R, Tresca DV. Patch Dynamics and Stability of Some California Kelp Communities. ECOL MONOGR 1984. [DOI: 10.2307/1942498] [Citation(s) in RCA: 384] [Impact Index Per Article: 9.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022]
|
25
|
|
26
|
Gerrodette T. Limited Dispersal Ability of a Solitary Coral. Bioscience 1981. [DOI: 10.2307/1308307] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022] Open
|