51
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Dolman SJ, Brakes P. Sustainable Fisheries Management and the Welfare of Bycaught and Entangled Cetaceans. Front Vet Sci 2018; 5:287. [PMID: 30525047 PMCID: PMC6262414 DOI: 10.3389/fvets.2018.00287] [Citation(s) in RCA: 15] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/05/2018] [Accepted: 10/30/2018] [Indexed: 11/19/2022] Open
Abstract
The incidental capture of cetaceans and other protected marine wildlife in fishing gear has significant welfare implications. Many thousands of cetaceans are bycaught in fishing gear in European waters and hundreds of thousands die globally. We can expect many more to survive, but suffer from such interactions. As marine policy focuses on "population level" impact assessments and "sustainability" of fishing to preserve fish populations, the impacts to the bycaught individual, and their wider social group, are often largely underestimated, despite the large numbers affected. The wide range of recorded injuries, including abrasions, cuts, bruising, and broken bones, along with the potential for panic associated with forced submersion, indicate that the welfare of bycaught cetaceans is, individually and collectively, very poor. Commercial fishing is the last human activity targeting wildlife (fish) on a grand scale where slaughter includes incidental killing of other large sapient wildlife on such a regular basis. Here, we review the compelling evidence of the short and long term welfare impacts of bycatch, and the progress made toward implementation of measures to understand and solve this significant welfare issue. We argue that policy decisions surrounding fishing do not adequately consider cetacean bycatch, including welfare impacts. Ultimately, there are welfare issues in all bycatch situations and suffering cannot plausibly be reduced without preventing bycatch. The well-documented welfare implications provide a strong argument for zero tolerance of cetacean bycatch and provide a compelling case for immediate action in fisheries where bycatch is taking place. The only way to reduce the suffering of bycaught cetaceans is to decrease, or ideally eliminate, the number of animals caught in fishing gear. Uncertainties around the scale of bycatch should not delay management, even where individual bycatch estimates are considered "sustainable." Lack of monitoring of sub-lethal impacts on populations may result in flawed impact assessments. We urge that animal welfare considerations should become an integral part of management decision-making in relation to bycatch globally. Enhanced, robust and transparent management systems are urgently required for the range of fisheries within which cetacean bycatch occurs, with the aim to better document and most importantly, work toward eliminating cetacean bycatch altogether.
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Affiliation(s)
- Sarah J. Dolman
- Whale and Dolphin Conservation (WDC), Chippenham, United Kingdom
| | - Philippa Brakes
- Whale and Dolphin Conservation (WDC), Chippenham, United Kingdom
- Centre for Ecology and Conservation, University of Exeter, Penryn, United Kingdom
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52
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Frainer G, Plön S, Serpa NB, Moreno IB, Huggenberger S. Sound Generating Structures of the Humpback DolphinSousa plumbea(Cuvier, 1829) and the Directionality in Dolphin Sounds. Anat Rec (Hoboken) 2018; 302:849-860. [DOI: 10.1002/ar.23981] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/22/2018] [Revised: 06/01/2018] [Accepted: 07/14/2018] [Indexed: 11/10/2022]
Affiliation(s)
- Guilherme Frainer
- Programa de Pós‐Graduação em Biologia Animal, Departamento de ZoologiaUniversidade Federal do Rio Grande do Sul 91540‐000 Porto Alegre Brazil
- Centro de Estudos CosteirosLimnológicos e Marinhos (CECLIMAR/UFRGS), Campus Litoral Norte, Universidade Federal do Rio Grande do Sul 95625‐000 Imbé Brazil
- Department II of AnatomyUniversity of Cologne 50924 Cologne Germany
| | - Stephanie Plön
- African Earth Observation Network (AEON) ‐Earth Stewardship Science Research Institute (ESSRI)Nelson Mandela University 6031 Port Elizabeth South Africa
| | - Nathalia B. Serpa
- Programa de Pós‐Graduação em Biologia Animal, Departamento de ZoologiaUniversidade Federal do Rio Grande do Sul 91540‐000 Porto Alegre Brazil
- Centro de Estudos CosteirosLimnológicos e Marinhos (CECLIMAR/UFRGS), Campus Litoral Norte, Universidade Federal do Rio Grande do Sul 95625‐000 Imbé Brazil
| | - Ignacio B. Moreno
- Programa de Pós‐Graduação em Biologia Animal, Departamento de ZoologiaUniversidade Federal do Rio Grande do Sul 91540‐000 Porto Alegre Brazil
- Centro de Estudos CosteirosLimnológicos e Marinhos (CECLIMAR/UFRGS), Campus Litoral Norte, Universidade Federal do Rio Grande do Sul 95625‐000 Imbé Brazil
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Saavedra C. strandCet: R package for estimating natural and non-natural mortality-at-age of cetaceans from age-structured strandings. PeerJ 2018; 6:e5768. [PMID: 30324031 PMCID: PMC6183513 DOI: 10.7717/peerj.5768] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/16/2018] [Accepted: 09/16/2018] [Indexed: 12/02/2022] Open
Abstract
Mortality is one of the most important parameters for the study of population dynamics. One of the main sources of information to calculate the mortality of cetaceans arises from the observed age-structure of stranded animals. A method based on an adaptation of a Heligman-Pollard model is proposed. A freely accessible package of functions (strandCet) has been created to apply this method in the statistical software R. Total, natural, and anthropogenic mortality-at-age is estimated using only data of stranded cetaceans whose age is known. Bayesian melding estimation with Incremental Mixture Importance Sampling is used for fitting this model. This characteristic, which accounts for uncertainty, further eases the estimation of credible intervals. The package also includes functions to perform life tables, Siler mortality models to calculate total mortality-at-age and Leslie matrices to derive population projections. Estimated mortalities can be tested under different scenarios. Population parameters as population growth, net production or generation time can be derived from population projections. The strandCet R package provides a new analytical framework to assess mortality in cetacean populations and to explore the consequences of management decisions using only stranding-derived data.
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Affiliation(s)
- Camilo Saavedra
- CO Vigo, Instituto Español de Oceanografía (IEO), Vigo, Spain
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54
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Lowry LF, Burkanov VN, Altukhov A, Weller DW, Reeves RR. Entanglement risk to western gray whales from commercial fisheries in the Russian Far East. ENDANGER SPECIES RES 2018. [DOI: 10.3354/esr00914] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022] Open
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55
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Díaz-Delgado J, Fernández A, Sierra E, Sacchini S, Andrada M, Vela AI, Quesada-Canales Ó, Paz Y, Zucca D, Groch K, Arbelo M. Pathologic findings and causes of death of stranded cetaceans in the Canary Islands (2006-2012). PLoS One 2018; 13:e0204444. [PMID: 30289951 PMCID: PMC6173391 DOI: 10.1371/journal.pone.0204444] [Citation(s) in RCA: 56] [Impact Index Per Article: 9.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/07/2018] [Accepted: 09/07/2018] [Indexed: 12/11/2022] Open
Abstract
This study describes the pathologic findings and most probable causes of death (CD) of 224 cetaceans stranded along the coastline of the Canary Islands (Spain) over a 7-year period, 2006-2012. Most probable CD, grouped as pathologic categories (PCs), was identified in 208/224 (92.8%) examined animals. Within natural PCs, those associated with good nutritional status represented 70/208 (33.6%), whereas, those associated with significant loss of nutritional status represented 49/208 (23.5%). Fatal intra- and interspecific traumatic interactions were 37/208 (17.8%). Vessel collisions included 24/208 (11.5%). Neonatal/perinatal pathology involved 13/208 (6.2%). Fatal interaction with fishing activities comprised 10/208 (4.8%). Within anthropogenic PCs, foreign body-associated pathology represented 5/208 (2.4%). A CD could not be determined in 16/208 (7.7%) cases. Natural PCs were dominated by infectious and parasitic disease processes. Herein, our results suggest that between 2006 and 2012, in the Canary Islands, direct human activity appeared responsible for 19% of cetaceans deaths, while natural pathologies accounted for 81%. These results, integrating novel findings and published reports, aid in delineating baseline knowledge on cetacean pathology and may be of value to rehabilitators, caregivers, diagnosticians and future conservation policies.
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Affiliation(s)
- Josué Díaz-Delgado
- Veterinary Histology and Pathology, Institute of Animal Health and Food Hygiene (IUSA), University of Las Palmas of Gran Canaria, Las Palmas of Gran Canaria, Spain
- Wildlife Comparative Pathology Laboratory, School of Veterinary Medicine and Animal Science, University of São Paulo, São Paulo, Brazil
| | - Antonio Fernández
- Veterinary Histology and Pathology, Institute of Animal Health and Food Hygiene (IUSA), University of Las Palmas of Gran Canaria, Las Palmas of Gran Canaria, Spain
| | - Eva Sierra
- Veterinary Histology and Pathology, Institute of Animal Health and Food Hygiene (IUSA), University of Las Palmas of Gran Canaria, Las Palmas of Gran Canaria, Spain
| | - Simona Sacchini
- Veterinary Histology and Pathology, Institute of Animal Health and Food Hygiene (IUSA), University of Las Palmas of Gran Canaria, Las Palmas of Gran Canaria, Spain
| | - Marisa Andrada
- Veterinary Histology and Pathology, Institute of Animal Health and Food Hygiene (IUSA), University of Las Palmas of Gran Canaria, Las Palmas of Gran Canaria, Spain
| | - Ana Isabel Vela
- Department of Animal Health, Veterinary College, Complutense University, Madrid, Spain
- Centro de Vigilancia Sanitaria Veterinaria (VISAVET). Complutense University, Madrid, Spain
| | - Óscar Quesada-Canales
- Veterinary Histology and Pathology, Institute of Animal Health and Food Hygiene (IUSA), University of Las Palmas of Gran Canaria, Las Palmas of Gran Canaria, Spain
| | - Yania Paz
- Veterinary Histology and Pathology, Institute of Animal Health and Food Hygiene (IUSA), University of Las Palmas of Gran Canaria, Las Palmas of Gran Canaria, Spain
| | - Daniele Zucca
- Veterinary Histology and Pathology, Institute of Animal Health and Food Hygiene (IUSA), University of Las Palmas of Gran Canaria, Las Palmas of Gran Canaria, Spain
| | - Kátia Groch
- Wildlife Comparative Pathology Laboratory, School of Veterinary Medicine and Animal Science, University of São Paulo, São Paulo, Brazil
| | - Manuel Arbelo
- Veterinary Histology and Pathology, Institute of Animal Health and Food Hygiene (IUSA), University of Las Palmas of Gran Canaria, Las Palmas of Gran Canaria, Spain
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56
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Rubini S, Frisoni P, Russotto C, Pedriali N, Mignone W, Grattarola C, Giorda F, Pautasso A, Barbieri S, Cozzi B, Mazzariol S, Gaudio RM. The diatoms test in veterinary medicine: A pilot study on cetaceans and sea turtles. Forensic Sci Int 2018; 290:e19-e23. [PMID: 30025595 DOI: 10.1016/j.forsciint.2018.06.033] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/14/2017] [Revised: 03/28/2018] [Accepted: 06/26/2018] [Indexed: 11/15/2022]
Abstract
Fishing activities are considered one of the most relevant threats for cetaceans and sea turtles conservation since these animals are sometimes found dead entangled in fishing gears. Currently, postmortem diagnosis is based mainly on the presence of nets and lines on the body and the related marks and injuries evident at gross examination. A more detailed and objective evidence is needed to clarify doubts cases and the diatoms technique, used in forensic human medicine, could support drowning diagnosis also in this field. Diatoms' investigation was implemented to be applied in marine vertebrate on 8 striped (Stenella coeruleoalba) and 1 bottlenose (Tursiops truncatus) dolphins and 5 sea turtles (Caretta caretta) stranded along the Italian coastlines with a likely cause of death hypothized on necropsies carried out by veterinary pathologists. Diatoms were microscopically searched in the bone marrow collected from long bones implementing protocols used in human medicine and their presence was observed in 4 cetaceans and 2 sea turtles. Despite a clear relation between diatoms' presence and amount and the likely cause of death was not proved due to the poor number of samples, the higher burden of diatoms was found in 3 animals deemed to be death for the interaction with human activity. Despite more studied are necessary to identify the possible relation between the cause of death and diatoms' findings, the present study implemented this technique to be adapted to marine animals, confirming its possible application also in veterinary forensic medicine.
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Affiliation(s)
- Silva Rubini
- Istituto Zooprofilattico Sperimentale della Lombardia e dell'Emilia Romagna (IZSLER), Sezione di Ferrara, Via Modena 483, 44044 Cassana, FE, Italy
| | - Paolo Frisoni
- Sezione di Medicina Legale, Dipartimento di Scienze Mediche, Università degli Studi di Ferrara, Ferrara, Via Fossato di Mortara 64/B, 44121 Ferrara, Italy
| | - Chiara Russotto
- Istituto Zooprofilattico Sperimentale della Lombardia e dell'Emilia Romagna (IZSLER), Sezione di Ferrara, Via Modena 483, 44044 Cassana, FE, Italy
| | - Natascia Pedriali
- Istituto Zooprofilattico Sperimentale della Lombardia e dell'Emilia Romagna (IZSLER), Sezione di Ferrara, Via Modena 483, 44044 Cassana, FE, Italy
| | - Walter Mignone
- Istituto Zooprofilattico Sperimentale del Piemonte, Liguria e Valle d'Aosta, Via Nizza 4, 18100 Imperia, Italy
| | - Carla Grattarola
- Istituto Zooprofilattico Sperimentale del Piemonte, Liguria e Valle d'Aosta, Via Bologna 148, 10154 Torino, Italy
| | - Federica Giorda
- Istituto Zooprofilattico Sperimentale del Piemonte, Liguria e Valle d'Aosta, Via Bologna 148, 10154 Torino, Italy
| | - Alessandra Pautasso
- Istituto Zooprofilattico Sperimentale del Piemonte, Liguria e Valle d'Aosta, Via Bologna 148, 10154 Torino, Italy
| | - Stefania Barbieri
- Scuola di Specializzazione in Igiene e Medicina Preventiva, Università di Ferrara, Ferrara, Via Fossato di Mortara 64/B, 44121 Ferrara, Italy
| | - Bruno Cozzi
- Dipartimento di Biomedicina Comparata e Alimentazione, Università degli Studi di Padova, AGRIPOLIS, Viale dell'Università 16, 35020 Legnaro, PD, Italy
| | - Sandro Mazzariol
- Dipartimento di Biomedicina Comparata e Alimentazione, Università degli Studi di Padova, AGRIPOLIS, Viale dell'Università 16, 35020 Legnaro, PD, Italy.
| | - Rosa Maria Gaudio
- Sezione di Medicina Legale, Dipartimento di Scienze Mediche, Università degli Studi di Ferrara, Ferrara, Via Fossato di Mortara 64/B, 44121 Ferrara, Italy
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57
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Mangel JC, Wang J, Alfaro-Shigueto J, Pingo S, Jimenez A, Carvalho F, Swimmer Y, Godley BJ. Illuminating gillnets to save seabirds and the potential for multi-taxa bycatch mitigation. ROYAL SOCIETY OPEN SCIENCE 2018; 5:180254. [PMID: 30109081 PMCID: PMC6083706 DOI: 10.1098/rsos.180254] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/08/2018] [Accepted: 06/04/2018] [Indexed: 05/31/2023]
Abstract
Bycatch in net fisheries is recognized as a major source of mortality for many marine species, including seabirds. Few mitigation solutions, however, have been identified. We assessed the effectiveness of illuminating fishing nets with green light emitting diodes (LEDs) to reduce the incidental capture of seabirds. Experiments were conducted in the demersal, set gillnet fishery of Constante, Peru and compared 114 pairs of control and illuminated nets. We observed captures of a total of 45 guanay cormorants (Phalacrocorax bougainvillii), with 39 caught in control nets and six caught in illuminated nets. Seabird bycatch in terms of catch-per-unit-effort was significantly (p < 0.05) higher in control nets than in illuminated nets, representing an 85.1% decline in the cormorant bycatch rate. This study, showing that net illumination reduces seabird bycatch and previous studies showing reductions in sea turtle bycatch without reducing target catch, indicates that net illumination can be an effective multi-taxa bycatch mitigation technique. This finding has broad implications for bycatch mitigation in net fisheries given LED technology's relatively low cost, the global ubiquity of net fisheries and the current paucity of bycatch mitigation solutions.
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Affiliation(s)
- Jeffrey C. Mangel
- ProDelphinus, Jose Galvez 780-E, Miraflores, Lima 18, Peru
- Centre for Ecology and Conservation, University of Exeter, Penryn, Cornwall TR10 9FE, UK
| | - John Wang
- NOAA, National Marine Fisheries Service, Pacific Islands Fisheries Science Center, Honolulu, HI 96818, USA
| | - Joanna Alfaro-Shigueto
- ProDelphinus, Jose Galvez 780-E, Miraflores, Lima 18, Peru
- Centre for Ecology and Conservation, University of Exeter, Penryn, Cornwall TR10 9FE, UK
- Facultad de Biologia Marina, Universidad Cientifica del Sur, Panamericana Sur Km 19, Villa, Lima, Peru
| | - Sergio Pingo
- ProDelphinus, Jose Galvez 780-E, Miraflores, Lima 18, Peru
| | - Astrid Jimenez
- ProDelphinus, Jose Galvez 780-E, Miraflores, Lima 18, Peru
| | - Felipe Carvalho
- NOAA, National Marine Fisheries Service, Pacific Islands Fisheries Science Center, Honolulu, HI 96818, USA
| | - Yonat Swimmer
- NOAA, National Marine Fisheries Service, Pacific Islands Fisheries Science Center, Honolulu, HI 96818, USA
| | - Brendan J. Godley
- Centre for Ecology and Conservation, University of Exeter, Penryn, Cornwall TR10 9FE, UK
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58
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Cruz MJ, Machete M, Menezes G, Rogan E, Silva MA. Estimating common dolphin bycatch in the pole-and-line tuna fishery in the Azores. PeerJ 2018; 6:e4285. [PMID: 29456883 PMCID: PMC5813588 DOI: 10.7717/peerj.4285] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/21/2017] [Accepted: 01/01/2018] [Indexed: 11/20/2022] Open
Abstract
Small-scale artisanal fisheries can have a significant negative impact in cetacean populations. Cetacean bycatch has been documented in the pole-and-line tuna fishery in the Azores with common dolphins being the species more frequently taken. Based on data collected by observers on ∼50% of vessels operating from 1998 to 2012, we investigate the influence of various environmental and fisheries-related factors in common dolphin bycatch and calculate fleet-wide estimates of total bycatch using design-based and model-based methods. Over the 15-year study dolphin bycatch occurred in less than 0.4% of the observed fishing events. Generalized additive modelling results suggest a significant relationship between common dolphin bycatch and duration of fishing events, sea surface temperature and location. Total bycatch calculated from the traditional stratified ratio estimation approach was 196 (95% CI: 186–205), while the negative binomial GAM estimated 262 (95% CI: 249–274) dolphins. Bycatch estimates of common dolphin were similar using statistical approaches suggesting that either of these methods may be used in future bycatch assessments for this fishery. Our work shows that rates of common dolphin bycatch in the pole-and-line tuna fishery in the Azores are low, despite considerable variations between years. Dolphins caught were released alive although the fate of these individuals is unknown. Continued monitoring will provide a better understanding of dolphin bycatch and more accurate estimates essential in the development of potential mitigation measures.
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Affiliation(s)
- Maria João Cruz
- Departamento de Oceanografia e Pescas, Universidade dos Açores, Horta, Açores, Portugal.,MARE-Marine and Environmental Sciences Centre and IMAR-Instituto do Mar, Universidade dos Açores, Horta, Açores, Portugal
| | - Miguel Machete
- MARE-Marine and Environmental Sciences Centre and IMAR-Instituto do Mar, Universidade dos Açores, Horta, Açores, Portugal
| | - Gui Menezes
- Departamento de Oceanografia e Pescas, Universidade dos Açores, Horta, Açores, Portugal.,MARE-Marine and Environmental Sciences Centre and IMAR-Instituto do Mar, Universidade dos Açores, Horta, Açores, Portugal
| | - Emer Rogan
- School of Biological, Earth and Environmental Sciences, University College Cork, Enterprise Centre, Distillery Fields, North Mall, Cork, Ireland
| | - Mónica A Silva
- MARE-Marine and Environmental Sciences Centre and IMAR-Instituto do Mar, Universidade dos Açores, Horta, Açores, Portugal.,Department of Biology, Woods Hole Oceanographic Institution, Woods Hole Oceanographic Institution, Woods Hole, MA, USA
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59
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Abstract
Declines of marine megafauna due to fisheries by-catch are thought to be mitigated by exclusion devices that release nontarget species. However, exclusion devices may instead conceal negative effects associated with by-catch caused by fisheries (i.e., unobserved or discarded by-catch with low postrelease survival or reproduction). We show that the decline of the endangered New Zealand (NZ) sea lion (Phocarctos hookeri) is linked to latent levels of by-catch occurring in sub-Antarctic trawl fisheries. Exclusion devices have been used since 2001 but have not slowed or reversed population decline. However, 35% of the variability in NZ sea lion pup production is explained by latent by-catch, and the population would increase without this factor. Our results indicate that exclusion devices can obscure rather than alleviate fishery impacts on marine megafauna.
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60
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Johnson AF, Caillat M, Verutes GM, Peter C, Junchompoo C, Long V, Ponnampalam LS, Lewison RL, Hines EM. Poor fisheries struggle with U.S. import rule. Science 2017; 355:1031-1032. [PMID: 28280175 DOI: 10.1126/science.aam9153] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/02/2022]
Affiliation(s)
- Andrew F Johnson
- Gulf of California Marine Program, Center for Marine Biodiversity and Conservation, Marine Biology Research Division, The Scripps Institution of Oceanography, La Jolla, San Diego CA 92093-0205, USA.
| | - Marjolaine Caillat
- Department of Geography and Environment, Romberg Tiburon Center for Environmental Studies, San Francisco State University, Tiburon, CA 94920, USA
| | | | - Cindy Peter
- Institute of Biodiversity and Environmental Conservation, University Malaysia Sarawak, Sarawak, Malaysia
| | - Chalatip Junchompoo
- Department of Marine and Coastal Resources, Eastern Marine and Coastal Resources Research Center, Rayong, Thailand
| | - Vu Long
- Vietnam Marine Mammal Network and The School of Ocean Sciences, Bangor University, Anglesey, LL59 5AB, UK
| | - Louisa S Ponnampalam
- Institute of Ocean and Earth Sciences, University of Malaya, Kuala Lumpur, Malaysia.,The MareCet Research Organization, Shah Alam, Malaysia
| | | | - Ellen M Hines
- Department of Geography and Environment, Romberg Tiburon Center for Environmental Studies, San Francisco State University, Tiburon, CA 94920, USA
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61
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Williams R, Ashe E, Gaut K, Gryba R, Moore JE, Rexstad E, Sandilands D, Steventon J, Reeves RR. Animal Counting Toolkit: a practical guide to small-boat surveys for estimating abundance of coastal marine mammals. ENDANGER SPECIES RES 2017. [DOI: 10.3354/esr00845] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022] Open
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62
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Williams R, Burgess MG, Ashe E, Gaines SD, Reeves RR. U.S. seafood import restriction presents opportunity and risk. Science 2017; 354:1372-1374. [PMID: 27980169 DOI: 10.1126/science.aai8222] [Citation(s) in RCA: 30] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/02/2022]
Affiliation(s)
- Rob Williams
- Oceans Initiative, Seattle, WA 98102, USA. .,Sea Mammal Research Unit, Scottish Oceans Institute, University of St. Andrews, St. Andrews KY16 8LB, Scotland UK
| | - Matthew G Burgess
- Sustainable Fisheries Group, Bren School of Environmental Science and Management, and Marine Science Institute, University of California, Santa Barbara, CA 93106, USA
| | - Erin Ashe
- Oceans Initiative, Seattle, WA 98102, USA.,Sea Mammal Research Unit, Scottish Oceans Institute, University of St. Andrews, St. Andrews KY16 8LB, Scotland UK
| | - Steven D Gaines
- Sustainable Fisheries Group, Bren School of Environmental Science and Management, and Marine Science Institute, University of California, Santa Barbara, CA 93106, USA
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63
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Soldevilla MS, Hildebrand JA, Frasier KE, Aichinger Dias L, Martinez A, Mullin KD, Rosel PE, Garrison LP. Spatial distribution and dive behavior of Gulf of Mexico Bryde’s whales: potential risk of vessel strikes and fisheries interactions. ENDANGER SPECIES RES 2017. [DOI: 10.3354/esr00834] [Citation(s) in RCA: 15] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022] Open
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64
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Assessing the relationship between cetacean strandings (Tursiops truncatus and Stenella coeruleoalba) and fishery pressure indicators in Sicily (Mediterranean Sea) within the framework of the EU Habitats Directive. EUR J WILDLIFE RES 2017. [DOI: 10.1007/s10344-017-1111-8] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
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65
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Asmutis-Silvia R, Barco S, Cole T, Henry A, Johnson A, Knowlton A, Landry S, Mattila D, Moore M, Robbins J, van der Hoop J. Rebuttal to published article "A review of ghost gear entanglement amongst marine mammals, reptiles and elasmobranchs" by M. Stelfox, J. Hudgins, and M. Sweet. MARINE POLLUTION BULLETIN 2017; 117:554-555. [PMID: 28012737 DOI: 10.1016/j.marpolbul.2016.11.052] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/20/2016] [Accepted: 11/22/2016] [Indexed: 06/06/2023]
Affiliation(s)
- Regina Asmutis-Silvia
- Whale and Dolphin Conservation, North America, 7 Nelson Street, 02360-4044 Plymouth, MA, USA.
| | - Susan Barco
- Virginia Aquarium & Marine Science Center Foundation, USA.
| | - Tim Cole
- NOAA's Northeast Fisheries Science Center, USA.
| | | | - Amanda Johnson
- Integrated Statistics under contract to the Greater Atlantic Regional Fisheries Office, USA.
| | | | | | - David Mattila
- International Whaling Commission and Center for Coastal Studies, USA.
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66
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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. CONSERVATION BIOLOGY : THE JOURNAL OF THE SOCIETY FOR CONSERVATION BIOLOGY 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] [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.
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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
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Wallace BP, Brosnan T, McLamb D, Rowles T, Ruder E, Schroeder B, Schwacke L, Stacy B, Sullivan L, Takeshita R, Wehner D. Effects of the Deepwater Horizon oil spill on protected marine species. ENDANGER SPECIES RES 2017. [DOI: 10.3354/esr00789] [Citation(s) in RCA: 22] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022] Open
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68
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Amano M, Kusumoto M, Abe M, Akamatsu T. Long-term effectiveness of pingers on a small population of finless porpoises in Japan. ENDANGER SPECIES RES 2017. [DOI: 10.3354/esr00776] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022] Open
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69
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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] [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
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Lopes K, Passos L, Rodrigues JG, Koenen F, Stiebens V, Székely T, Dutra A. Sea Turtle, Shark, and Dolphin Bycatch Rates by Artisanal and Semi-Industrial Fishers in Maio Island, Cape Verde. CHELONIAN CONSERVATION AND BIOLOGY 2016. [DOI: 10.2744/cb-1213.1] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
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71
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Liu M, Lin M, Turvey ST, Li S. Fishers' knowledge as an information source to investigate bycatch of marine mammals in the South China Sea. Anim Conserv 2016. [DOI: 10.1111/acv.12304] [Citation(s) in RCA: 24] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/27/2022]
Affiliation(s)
- M. Liu
- Sanya Key Laboratory of Marine Mammal and Marine Bioacoustics; Institute of Deep-Sea Science and Engineering; Chinese Academy of Sciences; Sanya China
- University of Chinese Academy of Sciences; Beijing China
| | - M. Lin
- Sanya Key Laboratory of Marine Mammal and Marine Bioacoustics; Institute of Deep-Sea Science and Engineering; Chinese Academy of Sciences; Sanya China
| | - S. T. Turvey
- Institute of Zoology; Zoological Society of London; London UK
| | - S. Li
- Sanya Key Laboratory of Marine Mammal and Marine Bioacoustics; Institute of Deep-Sea Science and Engineering; Chinese Academy of Sciences; Sanya China
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72
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Allen SJ, Bryant KA, Kraus RHS, Loneragan NR, Kopps AM, Brown AM, Gerber L, Krützen M. Genetic isolation between coastal and fishery-impacted, offshore bottlenose dolphin (Tursiopsspp.) populations. Mol Ecol 2016; 25:2735-53. [DOI: 10.1111/mec.13622] [Citation(s) in RCA: 30] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/18/2014] [Revised: 02/17/2016] [Accepted: 03/11/2016] [Indexed: 11/29/2022]
Affiliation(s)
- Simon J. Allen
- Cetacean Research Unit; School of Veterinary and Life Sciences; Murdoch University; Perth Western Australia 6150 Australia
- Centre for Marine Futures; School of Animal Biology and Oceans Institute; University of Western Australia; Perth Western Australia 6009 Australia
| | - Kate A. Bryant
- School of Veterinary and Life Sciences; Murdoch University; Murdoch Western Australia 6150 Australia
| | - Robert H. S. Kraus
- Department of Biology; University of Konstanz; 78457 Konstanz Germany
- Department of Migration and Immuno-Ecology; Max Planck Institute for Ornithology; Am Obstberg 1 78315 Radolfzell Germany
| | - Neil R. Loneragan
- School of Veterinary and Life Sciences; Murdoch University; Murdoch Western Australia 6150 Australia
| | - Anna M. Kopps
- Evolutionary Genetics Group; Department of Anthropology; University of Zurich; Winterthurerstrasse 190 8057 Zurich Switzerland
- Evolution and Ecology Research Centre; School of Biological; Earth and Environmental Sciences; University of New South Wales; Sydney New South Wales 2052 Australia
| | - Alexander M. Brown
- Cetacean Research Unit; School of Veterinary and Life Sciences; Murdoch University; Perth Western Australia 6150 Australia
| | - Livia Gerber
- Evolutionary Genetics Group; Department of Anthropology; University of Zurich; Winterthurerstrasse 190 8057 Zurich Switzerland
| | - Michael Krützen
- Evolutionary Genetics Group; Department of Anthropology; University of Zurich; Winterthurerstrasse 190 8057 Zurich Switzerland
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73
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Domiciano IG, Domit C, Broadhurst MK, Koch MS, Bracarense APFRL. Assessing Disease and Mortality among Small Cetaceans Stranded at a World Heritage Site in Southern Brazil. PLoS One 2016; 11:e0149295. [PMID: 26871703 PMCID: PMC4752507 DOI: 10.1371/journal.pone.0149295] [Citation(s) in RCA: 26] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/05/2015] [Accepted: 01/29/2016] [Indexed: 01/05/2023] Open
Abstract
Cetaceans are considered environmental sentinels and their health often reflects either anthropogenic or natural spatio-temporal disturbances. This study investigated the pathological findings and mortality of small cetaceans with the aim of detecting hazards and monitoring health trends in a high-biodiversity area. Between 2007 and 2012, 218 stranded cetaceans were recorded on the Paraná coast, southern Brazil. Fifty-seven (26.1%) of these animals, including 50 Sotalia guianensis, 2 Pontoporia blainvillei, 2 Stenella frontalis, 1 Stenella longirostris, 1 Tursiops truncatus and 1 Globicephala melas were necropsied and samples were collected for histopathology. Causes of death were determined in 46 of the 57 (80.7%) animals and most (30 or 65.2%) were ascribed to anthropogenic activities, including fisheries bycatch (28/30) and trauma (2/30). The remaining 16 fatalities were considered natural, and attributed to pneumonia (10/16), emaciation (3/16), septicemia (1/16), neonatal pathology (1/16) and choking via food obstruction (1/16). Irrespective of the cause, bronchointerstitial pneumonia, associated with parasitism, lymphadenitis and membranous glomerulonephritis were common findings among all fatalities. These results suggest, that while anthropogenic activities are a leading cause of cetacean strandings in Paraná, underlying pre-existing diseases may contribute towards deaths. Although the studied area is considered a biosphere reserve by UNESCO, complex anthropogenic and natural interactions might be occurring, increasing cetacean susceptibility to hazards. This study may help facilitate developing an effective conservation plan for coastal cetaceans focusing on reducing fisheries interactions, habitat degradation and pollution as mechanisms for ultimately increasing species resilience.
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Affiliation(s)
- Isabela G. Domiciano
- Laboratory of Animal Pathology, Department of Veterinary Preventive Medicine, Universidade Estadual de Londrina, Londrina, Paraná, Brazil
- Laboratory of Ecology and Conservation, Centro de Estudos do Mar, Universidade Federal do Paraná, Pontal do Paraná, Paraná, Brazil
| | - Camila Domit
- Laboratory of Ecology and Conservation, Centro de Estudos do Mar, Universidade Federal do Paraná, Pontal do Paraná, Paraná, Brazil
| | - Matt K. Broadhurst
- NSW Department of Primary Industries, Fisheries Conservation Technology Unit, Coffs Harbour, Australia
- Marine and Estuarine Ecology Unit, School of Biological Sciences, University of Queensland, Brisbane, Australia
| | - Mariana S. Koch
- Laboratory of Animal Pathology, Department of Veterinary Preventive Medicine, Universidade Estadual de Londrina, Londrina, Paraná, Brazil
- Laboratory of Ecology and Conservation, Centro de Estudos do Mar, Universidade Federal do Paraná, Pontal do Paraná, Paraná, Brazil
| | - Ana Paula F. R. L. Bracarense
- Laboratory of Animal Pathology, Department of Veterinary Preventive Medicine, Universidade Estadual de Londrina, Londrina, Paraná, Brazil
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74
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Prado JHF, Mattos PH, Silva KG, Secchi ER. Long-Term Seasonal and Interannual Patterns of Marine Mammal Strandings in Subtropical Western South Atlantic. PLoS One 2016; 11:e0146339. [PMID: 26814667 PMCID: PMC4729480 DOI: 10.1371/journal.pone.0146339] [Citation(s) in RCA: 50] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/06/2015] [Accepted: 12/16/2015] [Indexed: 11/18/2022] Open
Abstract
Understanding temporal patterns of marine mammal occurrence is useful for establishing conservation strategies. We used a 38 yr-long dataset spanning 1976 to 2013 to describe temporal patterns and trends in marine mammal strandings along a subtropical stretch of the east coast of South America. This region is influenced by a transitional zone between tropical and temperate waters and is considered an important fishing ground off Brazil. Generalized Additive Models were used to evaluate the temporal stranding patterns of the most frequently stranded species. Forty species were documented in 12,540 stranding events. Franciscana (n = 4,574), South American fur seal, (n = 3,419), South American sea lion (n = 2,049), bottlenose dolphins (n = 293) and subantarctic fur seal (n = 219) were the most frequently stranded marine mammals. The seasonality of strandings of franciscana and bottlenose dolphin coincided with periods of higher fishing effort and strandings of South American and subantarctic fur seals with post-reproductive dispersal. For South American sea lion the seasonality of strandings is associated with both fishing effort and post-reproductive dispersal. Some clear seasonal patterns were associated with occurrence of cold- (e.g. subantarctic fur seal) and warm-water (e.g. rough-toothed dolphin) species in winter and summer, respectively. Inter-annual increases in stranding rate were observed for franciscana and South American fur seal and these are likely related to increased fishing effort and population growth, respectively. For subantarctic fur seal the stranding rate showed a slight decline while for bottlenose dolphin it remained steady. No significant year to year variation in stranding rate was observed for South American sea lion. The slight decrease in frequency of temperate/polar marine mammals and the increased occurrence of subtropical/tropical species since the late 1990s might be associated with environmental changes linked to climate change. This long-term study indicates that temporal stranding patterns of marine mammals might be explained by either fishing-related or environmental factors.
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Affiliation(s)
- Jonatas H. F. Prado
- Instituto de Oceanografia, Laboratório de Ecologia e Conservação da Megafauna Marinha, Universidade Federal do Rio Grande, Rio Grande, Brazil
- * E-mail:
| | - Paulo H. Mattos
- Instituto de Oceanografia, Laboratório de Gerenciamento Costeiro, Universidade Federal do Rio Grande, Rio Grande, Brazil
| | - Kleber G. Silva
- Núcleo de Educação e Monitoramento Ambiental, Rio Grande, Brazil
| | - Eduardo R. Secchi
- Instituto de Oceanografia, Laboratório de Ecologia e Conservação da Megafauna Marinha, Universidade Federal do Rio Grande, Rio Grande, Brazil
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75
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Paudel S, Levesque JC, Saavedra C, Pita C, Pal P. Characterization of the artisanal fishing communities in Nepal and potential implications for the conservation and management of Ganges River Dolphin (Platanista gangetica gangetica). PeerJ 2016; 4:e1563. [PMID: 26788434 PMCID: PMC4715443 DOI: 10.7717/peerj.1563] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/24/2015] [Accepted: 12/14/2015] [Indexed: 11/30/2022] Open
Abstract
The Ganges River dolphin (Platanista gangetica gangetica) (GRD) is classified as one of the most endangered of all cetaceans in the world and the second scarcest freshwater cetacean. The population is estimated to be less than 2,000 individuals. In Nepal’s Narayani, Sapta Koshi, and Karnali river systems, survival of GRD continues to be threatened by various anthropogenic activities, such as dam construction and interactions with artisanal fisheries. A basic description of the geographic scope, economics, and types of gear used in these fisheries would help managers understand the fishery-dolphin interaction conflict and assist with developing potential solutions. The main goal was to provide new information on the artisanal fishing communities in Nepal. The specific objectives were to identify, compile, and investigate the demographics, economics, fishing characteristics, and perception of fishermen about GRD conservation in the Narayani, Sapta Koshi, and Karnali rivers so conservation managers can develop and implement a potential solution to the GRD-fishery interaction problem in Nepal. Based on 169 interviews, 79% of Nepalese fishermen indicated fishing was their primary form of income. Fishermen reported fishing effort was greater in summer than winter; greatest in the afternoon (14:30 hrs ± 0:27) and during low water level conditions; and gear was set 4.8 ± 0.2 days/week. Fishermen reported using eight different types of monofilament nets (gillnets and cast nets). Sixty percent used gillnets less than 10 m long, and nearly 30% preferred gillnets between 10 and 100 m long; a few used gillnets longer than 100 m. Most fishermen reported they believed education, awareness, and changing occupations were important for GRD conservation, but they indicated that alternative occupational options were currently limited in Nepal. Nepalese fishermen acknowledged that fisheries posed a risk to GRD, but they believed water pollution, and dam/irrigation developments were the greatest threats.
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Affiliation(s)
- Shambhu Paudel
- Kathmandu Forestry College and The Himalaya , Kathmandu , Nepal
| | - Juan C Levesque
- Environmental Resources Management, Impact, Assessment, and Planning Division , Tampa, Florida , United States
| | | | - Cristina Pita
- Department of Environment and Planning & Center for Environmental and Marine Studies (CESAM), University of Aveiro , Aveiro , Portugal
| | - Prabhat Pal
- Department of Soil Conservation and Watershed Management, Ministry of Forest and Soil Conservation, Nepal, The Himalaya , Kathmandu , Nepal
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Di Tullio JC, Fruet PF, Secchi ER. Identifying critical areas to reduce bycatch of coastal common bottlenose dolphins Tursiops truncatus in artisanal fisheries of the subtropical western South Atlantic. ENDANGER SPECIES RES 2015. [DOI: 10.3354/esr00698] [Citation(s) in RCA: 27] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022] Open
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77
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Cerchio S, Andrianarivelo N, Andrianantenaina B. Ecology and Conservation Status of Indian Ocean Humpback Dolphins (Sousa plumbea) in Madagascar. ADVANCES IN MARINE BIOLOGY 2015; 72:163-199. [PMID: 26555626 DOI: 10.1016/bs.amb.2015.09.004] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/05/2023]
Abstract
The Indian Ocean humpback dolphin (Sousa plumbea) has been studied in several range states in the Southwest Indian Ocean, however little information exists on populations in Madagascar. Here, we review available literature and describe a study on S. plumbea conducted between 2004 and 2013 on the west coast of Madagascar, involving boat-based field surveys in the southwest and northwest regions, and interview surveys with local fishers from villages along most of the west coast. Field surveys in the southwest region of Anakao/St. Augustine Bay revealed low encounter rates and mean group size, and markedly declining trends in both from 1999 to 2013. Conversely, in the northwest region around Nosy Be and Nosy Iranja, encounter rates were higher, as were mean group sizes, suggesting an apparently more abundant and less impacted population. Interview surveys revealed by-catch of coastal dolphins along the entire west coast, including S. plumbea, as well as other species. Directed hunting, including drive hunts of groups of dolphins, was reported primarily in the southern regions, in the range of the Vezo Malagasy ethnicity; however, there was evidence of hunting starting in one area in the northwest, where hunting dolphins is normally considered taboo for the predominant Sakalava ethnicity. Thus, the conservation status of S. plumbea in Madagascar appears to be spatially heterogeneous, with some areas where the local population is apparently more impacted than others. Conservation measures are recommended to mitigate further decline in the southwest of Madagascar, while protecting habitat and ensuring resilience in the northwest.
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Affiliation(s)
- Salvatore Cerchio
- New England Aquarium, Central Wharf, Boston, Massachusetts, USA; Woods Hole Oceanographic Institution, Woods Hole, Massachusetts, USA.
| | - Norbert Andrianarivelo
- Institut Halieutique et des Sciences Marines, Universite de Toliara, Toliara, Madagascar
| | - Boris Andrianantenaina
- Institut Halieutique et des Sciences Marines, Universite de Toliara, Toliara, Madagascar
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Culik B, von Dorrien C, Müller V, Conrad M. Synthetic communication signals influence wild harbour porpoise ( Phocoena phocoena) behaviour. BIOACOUSTICS 2015. [DOI: 10.1080/09524622.2015.1023848] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/23/2022]
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80
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Briscoe DK, Hiatt S, Lewison R, Hines E. Modeling habitat and bycatch risk for dugongs in Sabah, Malaysia. ENDANGER SPECIES RES 2014. [DOI: 10.3354/esr00600] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022] Open
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81
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Patterns of dolphin bycatch in a north-western Australian trawl fishery. PLoS One 2014; 9:e93178. [PMID: 24695338 PMCID: PMC3973695 DOI: 10.1371/journal.pone.0093178] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/29/2013] [Accepted: 03/03/2014] [Indexed: 11/30/2022] Open
Abstract
The bycatch of small cetaceans in commercial fisheries is a global wildlife management problem. We used data from skippers' logbooks and independent observers to assess common bottlenose dolphin (Tursiops truncatus) bycatch patterns between 2003 and 2009 in the Pilbara Trawl Fishery, Western Australia. Both datasets indicated that dolphins were caught in all fishery areas, across all depths and throughout the year. Over the entire datasets, observer reported bycatch rates (n = 52 dolphins in 4,124 trawls, or 12.6 dolphins/1,000 trawls) were ca. double those reported by skippers (n = 180 dolphins in 27,904 trawls, or 6.5 dolphins/1,000 trawls). Generalised Linear Models based on observer data, which better explained the variation in dolphin bycatch, indicated that the most significant predictors of dolphin catch were: (1) vessel - one trawl vessel caught significantly more dolphins than three others assessed; (2) time of day – the lowest dolphin bycatch rates were between 00:00 and 05:59; and (3) whether nets included bycatch reduction devices (BRDs) - the rate was reduced by ca. 45%, from 18.8 to 10.3 dolphins/1,000 trawls, after their introduction. These results indicated that differences among vessels (or skippers' trawling techniques) and dolphin behavior (a diurnal pattern) influenced the rates of dolphin capture; and that spatial or seasonal adjustments to trawling effort would be unlikely to significantly reduce dolphin bycatch. Recent skipper's logbook data show that dolphin bycatch rates have not declined since those reported in 2006, when BRDs were introduced across the fishery. Modified BRDs, with top-opening escape hatches from which dolphins might escape to the surface, may be a more effective means of further reducing dolphin bycatch. The vulnerability of this dolphin population to trawling-related mortality cannot be assessed in the absence of an ongoing observer program and without information on trawler-associated dolphin community size, broader dolphin population size and connectivity with adjacent populations.
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82
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Global patterns of marine mammal, seabird, and sea turtle bycatch reveal taxa-specific and cumulative megafauna hotspots. Proc Natl Acad Sci U S A 2014; 111:5271-6. [PMID: 24639512 DOI: 10.1073/pnas.1318960111] [Citation(s) in RCA: 119] [Impact Index Per Article: 11.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
Recent research on ocean health has found large predator abundance to be a key element of ocean condition. Fisheries can impact large predator abundance directly through targeted capture and indirectly through incidental capture of nontarget species or bycatch. However, measures of the global nature of bycatch are lacking for air-breathing megafauna. We fill this knowledge gap and present a synoptic global assessment of the distribution and intensity of bycatch of seabirds, marine mammals, and sea turtles based on empirical data from the three most commonly used types of fishing gears worldwide. We identify taxa-specific hotspots of bycatch intensity and find evidence of cumulative impacts across fishing fleets and gears. This global map of bycatch illustrates where data are particularly scarce--in coastal and small-scale fisheries and ocean regions that support developed industrial fisheries and millions of small-scale fishers--and identifies fishing areas where, given the evidence of cumulative hotspots across gear and taxa, traditional species or gear-specific bycatch management and mitigation efforts may be necessary but not sufficient. Given the global distribution of bycatch and the mitigation success achieved by some fleets, the reduction of air-breathing megafauna bycatch is both an urgent and achievable conservation priority.
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Niemi M, Auttila M, Viljanen M, Kunnasranta M. Movement data and their application for assessing the current distribution and conservation needs of the endangered Saimaa ringed seal. ENDANGER SPECIES RES 2012. [DOI: 10.3354/esr00468] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022] Open
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