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Chou LS, Yao CJ, Wang MC, Chi WL, Ho Y, Yang WC. Cetacean Stranding Response Program and Spatial-Temporal Analysis in Taiwan, 1994-2018. Animals (Basel) 2024; 14:1823. [PMID: 38929442 PMCID: PMC11200669 DOI: 10.3390/ani14121823] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/05/2024] [Revised: 06/16/2024] [Accepted: 06/17/2024] [Indexed: 06/28/2024] Open
Abstract
A national cetacean stranding response program in Taiwan has evolved significantly in the past three decades. Initially co-ordinated by National Taiwan University from 1994, the program transitioned to the Taiwan Cetacean Society in 1999, and local governments took on a more prominent role after 2009. A comprehensive stranding database (1994-2018) has been maintained, which documented 1320 stranding events involving 1698 animals from at least 27 species. The most commonly stranded species include finless porpoises, bottlenose dolphins, Kogia spp., and Risso's dolphins. The stranding rates varied annually and seasonally, with increases noted from an average of 16 events per year for the first 3 years to 44-58 events per year between 1997 and 2015, and a sharp rise to over 90 events per year for the period of the last three years. Seasonal variations were also significant, with higher stranding rates during the northeastern monsoon (NEM, October to next April) than that during southwestern monsoon (SWM, May to September). From the aspect of distribution, more frequent and even strandings occurred along the coast of northern Taiwan, while mass strandings were concentrated in the southwestern counties during NEM. Among all strandings, 390 events (29.5%) and 660 animals (38.9%) were live ones. Under great effort in rescuing and rehabilitating 52 cases, 15 cetacean individuals have been released since 2000. Additionally, there have been 56 mass strandings involving at least 11 species since 1994, predominated by pygmy killer whales, particularly during the NEM season along the southwest coast. This study not only contributes to our understanding of the stranding patterns and diversity of the cetaceans in Taiwan, but also provides valuable insights for future conservation strategies on cetaceans in the western Pacific.
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Affiliation(s)
- Lien-Siang Chou
- Institute of Ecological and Evolutionary Biology, National Taiwan University, Taipei 106216, Taiwan; (L.-S.C.); (Y.H.)
| | - Chiou-Ju Yao
- Department of Biology, National Museum of Natural Science, Taichung 404023, Taiwan
- Department of Life Science, National Chung Hsing University, Taichung 402202, Taiwan
| | - Ming-Chih Wang
- Taiwan Cetacean Society, New Taipei 248020, Taiwan; (M.-C.W.); (W.-L.C.)
| | - Wei-Lien Chi
- Taiwan Cetacean Society, New Taipei 248020, Taiwan; (M.-C.W.); (W.-L.C.)
- Department of Post-Baccalaureate Veterinary Medicine, College of Medical and Health Science, Asia University, Taichung 413305, Taiwan
| | - Yun Ho
- Institute of Ecological and Evolutionary Biology, National Taiwan University, Taipei 106216, Taiwan; (L.-S.C.); (Y.H.)
| | - Wei-Cheng Yang
- Taiwan Cetacean Society, New Taipei 248020, Taiwan; (M.-C.W.); (W.-L.C.)
- School of Veterinary Medicine, National Taiwan University, Taipei 106216, Taiwan
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García-Cegarra AM, Hall A, Martínez-López E. Bycatch and pollution are the main threats for Burmeister's porpoises inhabiting a high-industrialized bay in the Humboldt Current System. ENVIRONMENTAL RESEARCH 2024; 251:118621. [PMID: 38492834 DOI: 10.1016/j.envres.2024.118621] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/22/2023] [Revised: 03/01/2024] [Accepted: 03/02/2024] [Indexed: 03/18/2024]
Abstract
Pollution and bycatch are two of the main threats for cetaceans worldwide. These threats are exacerbated for nearshore species particularly for those in regions with intense industrial and fishing activities. Burmeister's porpoise is endemic to South America, has a Near Threatened conservation status because of long-term mortality in fisheries. Burmeister's porpoise occur in Mejillones Bay, northern Chile, a hot spot for heavy metals pollution from the mining industry and an intense industrial and artisanal purse-seine fishing area. From 2018 to 2021, we conducted systematic marine surveys to assess the abundance, distribution and habitat use of Burmeister's porpoises. We responded to stranding reports from 2018 to 2022, and necropsied nine individuals. From five of these, we analyzed the metal concentrations (As, Cd, Cr, Cu, Pb, Hg, Se and Zn) in muscle and skin tissues. Results showed an abundance of 76.17 individuals (CV = 25.9%) and an average density of 0.45 individuals/km2 (CV = 26%). Burmeister's porpoises were observed year round, 22.2% were mother-calf pairs present in austral summer at an average of 90.6 m depth in the southwestern bound of the bay. Two-thirds of stranded specimens died due to bycatch and one died due to bottlenose dolphin (Tursiops truncatus) attack. We report a dead Burmeister's porpoise positive for avian flu virus A (H5N1). Metals analyzed were found in muscle and skin tissues of stranded Burmeister's porpoises in the following order (Zn > Cu > Cr > As > Hg > Pb > Cd). Although we could not assess pollution as a cause of mortality, Cr, As and Pb concentrations exceeded the concentrations found in other porpoises species worldwide. We conclude that bycatch and pollution as the main threats for Burmeister's porpoise survival in northern Chile. Future studies should investigate the use of acoustic deterrent alarms to mitigate the bycatch in the bay and consider the Burmeister's porpoise as a sentinel species of pollution in northern Chilean coast.
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Affiliation(s)
- Ana M García-Cegarra
- Instituto de Ciencias Naturales Alexander von Humboldt, Facultad de Ciencias del Mar y Recursos Biológicos, Universidad de Antofagasta, 1240000, Antofagasta, Chile; CETALAB, Laboratorio de Estudio de Megafauna Marina, 1240000, Antofagasta, Chile.
| | - Anna Hall
- Porpoise Conservation Society, British Columbia (S-63931), Canada; Sea View Marine Sciences, Victoria, V9C 4C5, British Columbia, Canada
| | - Emma Martínez-López
- Area of Toxicology, Oceanosphera group. Department of Health Sciences, Faculty of Veterinary Medicine, University of Murcia, 30100, Murcia, Spain; Toxicology and Risk Assessment Group, Biomedical Research Institute of Murcia (IMIB-Arrixaca), University of Murcia, 30100, Murcia, Spain
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3
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Sarlin PJ, Morris S, Geethambika SB, Gopi L, Muraleedharan M, Thomas JA, Savitha G, Joseph P. Halocercus lagenorhynchi infection in a stranded striped dolphin Stenella coeruleoalba (Meyen, 1833) on the Southwest coastline of India. J Parasit Dis 2024; 48:168-179. [PMID: 38440750 PMCID: PMC10908710 DOI: 10.1007/s12639-024-01646-6] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/02/2023] [Accepted: 12/29/2023] [Indexed: 03/06/2024] Open
Abstract
Necropsy on a striped dolphin Stenella coeruleoalba (Meyen, 1833) entangled in ghost fishing net and dead while rescuing yielded some helminth parasites, later identified as Halocercus lagenorhynchi. DNA barcoding of the host and parasite and the phylogenetic analysis of the parasite was conducted. This study provides valuable information towards establishing basal data of marine mammal parasite diversity and distribution in the Indian waters. We believe this is the first report of the occurrence of Halocercus lagenorhynchi in marine mammals in India.
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Affiliation(s)
- Pathissery John Sarlin
- PG and Research Department of Zoology, Fatima Mata National College (Autonomous), University of Kerala, Kollam, India
| | - Sancia Morris
- Institute of Chemical Technology Mumbai, IOC Bhuvneshwar Odisha, Bhubaneswar, India
| | | | - Lijin Gopi
- School of Medicine and Public Health, Department of Medicine, University of Wisconsin, Madison, USA
| | - Megha Muraleedharan
- PG and Research Department of Zoology, Fatima Mata National College (Autonomous), University of Kerala, Kollam, India
| | - Jeniffer Ann Thomas
- PG and Research Department of Zoology, Fatima Mata National College (Autonomous), University of Kerala, Kollam, India
| | - Gayathry Savitha
- PG and Research Department of Zoology, Fatima Mata National College (Autonomous), University of Kerala, Kollam, India
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Kraft S, Rodríguez F, Olavarría C, Poulin E, Pérez-Álvarez MJ. Genetic Analysis as a Tool to Improve the Monitoring of Stranded Cetaceans in Chile. BIOLOGY 2023; 12:biology12050748. [PMID: 37237561 DOI: 10.3390/biology12050748] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/31/2023] [Revised: 04/09/2023] [Accepted: 04/28/2023] [Indexed: 05/28/2023]
Abstract
Cetacean strandings are a valuable source of information for several studies from species richness to conservation and management. During the examination of strandings, taxonomic and sex identification might be hindered for several reasons. Molecular techniques are valuable tools to obtain that missing information. This study evaluates how gene fragment amplification protocols can support the records of strandings done in the field in Chile by identifying, corroborating, or correcting the identification of the species and sex of the recorded individuals. Through a collaboration between a scientific laboratory and government institution in Chile, 63 samples were analyzed. Thirty-nine samples were successfully identified to the species level. In total, 17 species of six families were detected, including six species of conservation interest. Of the 39 samples, 29 corresponded to corroborations of field identifications. Seven corresponded to unidentified samples and three to corrected misidentifications, adding up to 28% of the identified samples. Sex was successfully identified for 58 of the 63 individuals. Twenty were corroborations, 34 were previously unidentified, and four were corrections. Applying this method improves the stranding database of Chile and provides new data for future management and conservation tasks.
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Affiliation(s)
- Sebastián Kraft
- Centro de Ciências do Mar (CCMAR), Universidade do Algarve, 8005-139 Faro, Portugal
- Laboratorio de Ecología Molecular, Departamento de Ciencias Ecológicas, Instituto de Ecología y Biodiversidad, Facultad de Ciencias, Universidad de Chile, Santiago 7800003, Chile
| | - Francisca Rodríguez
- Laboratorio de Ecología Molecular, Departamento de Ciencias Ecológicas, Instituto de Ecología y Biodiversidad, Facultad de Ciencias, Universidad de Chile, Santiago 7800003, Chile
- Millennium Institute Biodiversity of Antarctic and Subantarctic Ecosystems (BASE), Santiago 7800003, Chile
| | - Carlos Olavarría
- Centro de Estudios Avanzados en Zonas Áridas (CEAZA), La Serena 1720256, Chile
- Eutropia, Centro de Investigación, Santiago 8320238, Chile
| | - Elie Poulin
- Laboratorio de Ecología Molecular, Departamento de Ciencias Ecológicas, Instituto de Ecología y Biodiversidad, Facultad de Ciencias, Universidad de Chile, Santiago 7800003, Chile
- Millennium Institute Biodiversity of Antarctic and Subantarctic Ecosystems (BASE), Santiago 7800003, Chile
| | - María José Pérez-Álvarez
- Laboratorio de Ecología Molecular, Departamento de Ciencias Ecológicas, Instituto de Ecología y Biodiversidad, Facultad de Ciencias, Universidad de Chile, Santiago 7800003, Chile
- Millennium Institute Biodiversity of Antarctic and Subantarctic Ecosystems (BASE), Santiago 7800003, Chile
- Eutropia, Centro de Investigación, Santiago 8320238, Chile
- Escuela de Medicina Veterinaria, Facultad de Medicina y Ciencias de la Salud, Universidad Mayor, Santiago 8580745, Chile
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Boys RM, Beausoleil NJ, Pawley MDM, Littlewood KE, Betty EL, Stockin KA. Identification of potential welfare and survival indicators for stranded cetaceans through international, interdisciplinary expert opinion. ROYAL SOCIETY OPEN SCIENCE 2022; 9:220646. [PMID: 36312566 PMCID: PMC9554527 DOI: 10.1098/rsos.220646] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 05/16/2022] [Accepted: 09/16/2022] [Indexed: 06/16/2023]
Abstract
Management of live cetacean strandings generally focuses on refloating animals, yet there is a lack of scientific data to inform decision-making. Valid indicators that are practical to measure are needed to assess welfare status and survival likelihood for stranded cetaceans. The Delphi method was applied to gather international and interdisciplinary expert opinion to provide face validity to potential indicators of stranded cetacean welfare and survival likelihood. Two online questionnaires were conducted. In the first questionnaire these experts identified potential indicators of stranded cetacean welfare and survival likelihood. These indicators were subsequently scored by the same experts in questionnaire two, based on their value for assessing welfare/survival likelihood and being practical to measure. Indicators considered valuable and practical for assessing welfare and survival likelihood at strandings included animal-based indices of body and skin condition, signs of physical trauma, respiration rate and various behaviours. Resource-/management-based indicators related mainly to human intervention and should be correlated with animal-based indices to provide relevant evaluations. Importantly, inextricable links between welfare and survival for stranded cetaceans are emphasized, with 90% of indicators being similar for both. Investigations into these indicators should be conducted to develop a practical, science-based assessment framework to inform decision-making during stranding events.
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Affiliation(s)
- Rebecca M. Boys
- Cetacean Ecology Research Group, School of Natural Sciences, College of Sciences, Massey University, Private Bag 102-904, Auckland, New Zealand
| | - Ngaio J. Beausoleil
- Animal Welfare Science and Bioethics Centre, School of Veterinary Science, College of Sciences, Massey University, Private Bag 11-222, Palmerston North, New Zealand
| | - Matthew D. M. Pawley
- School of Mathematical and Computational Sciences, College of Sciences, Massey University, Private Bag 102-904, Auckland, New Zealand
| | - Katherine E. Littlewood
- Animal Welfare Science and Bioethics Centre, School of Veterinary Science, College of Sciences, Massey University, Private Bag 11-222, Palmerston North, New Zealand
| | - Emma L. Betty
- Cetacean Ecology Research Group, School of Natural Sciences, College of Sciences, Massey University, Private Bag 102-904, Auckland, New Zealand
| | - Karen A. Stockin
- Cetacean Ecology Research Group, School of Natural Sciences, College of Sciences, Massey University, Private Bag 102-904, Auckland, New Zealand
- Animal Welfare Science and Bioethics Centre, School of Veterinary Science, College of Sciences, Massey University, Private Bag 11-222, Palmerston North, New Zealand
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Dudhat S, Pande A, Nair A, Mondal I, Srinivasan M, Sivakumar K. Spatio-temporal analysis identifies marine mammal stranding hotspots along the Indian coastline. Sci Rep 2022; 12:4128. [PMID: 35260571 PMCID: PMC8904828 DOI: 10.1038/s41598-022-06156-0] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/31/2021] [Accepted: 01/07/2022] [Indexed: 11/09/2022] Open
Abstract
Marine mammal strandings provide vital information on species' life histories, population health and status of marine ecosystems. Opportunistic reporting of strandings also serve as a powerful low-cost tool for monitoring these elusive mammals. We collated data over ~ 270 years available through various open access databases, reports and publications. Annual strandings along the Indian coast (mean = 11.25 ± SE 9.1) increased in the last two years of the study (2015-2017, mean = 27.66 ± SE 8.5 strandings /year). We found that stranding events spike during June-September along the west coast and during December-January along the east coast. We identified several sections of the coastline, such as Mumbai (0.38 strandings/km), Kozhikode (0.28 strandings/km), Tuticorin (0.4 strandings/km), Rameswaram (1.82 strandings/km), Chennai (0.32 strandings/km) and Bhubaneshwar (0.26 strandings/km) with a higher number of stranded animals reported. Emerging Hotspot Analysis located new and consecutive hotspots along the north-west coast, and sporadic hotspots along the south-east coast. We recommend establishing regional stranding response centres at the identified hotspots coordinated by a National Stranding Centre with adequately trained personnel and central funding support. Regular stranding response training programs for field veterinarians, and frontline personnel of State Forest Departments near stranding hotspots would provide an improved understanding of marine mammal health and threats in Indian waters. Further, the suggested National Stranding Centre needs to maintain a 'National Stranding Database' for long-term marine mammal conservation planning in India.
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Affiliation(s)
- Sohini Dudhat
- Department of Endangered Species Management, Wildlife Institute of India, Chandrabani, Dehradun, Uttarakhand, 248001, India
| | - Anant Pande
- Department of Endangered Species Management, Wildlife Institute of India, Chandrabani, Dehradun, Uttarakhand, 248001, India.
| | - Aditi Nair
- Department of Endangered Species Management, Wildlife Institute of India, Chandrabani, Dehradun, Uttarakhand, 248001, India
| | - Indranil Mondal
- Department of Endangered Species Management, Wildlife Institute of India, Chandrabani, Dehradun, Uttarakhand, 248001, India
| | - Mridula Srinivasan
- Marine Mammal and Turtle Division, Southeast Fisheries Science Center, National Marine Fisheries Service, 75 Virginia Beach Drive, Miami, FL, USA
| | - Kuppusamy Sivakumar
- Department of Endangered Species Management, Wildlife Institute of India, Chandrabani, Dehradun, Uttarakhand, 248001, India.
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Ortiz-Alvarez C, Guidino C, Verhaegen C, Alfaro-Shigueto J, Mangel JC. Lessons from 12 years of marine fauna stranding data in the south of Peru. ENVIRONMENTAL MONITORING AND ASSESSMENT 2022; 194:142. [PMID: 35118565 DOI: 10.1007/s10661-022-09782-3] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/13/2021] [Accepted: 01/15/2022] [Indexed: 06/14/2023]
Abstract
In Peru, while several mass mortality events have been reported in the last two decades, there has been minimal systematic stranding monitoring. In this study, we report on repeated stranding monitoring that took place between October 2003 and October 2015, at Ite beach, Tacna (17° 54' 47" S 70° 58' 21" W). The objectives of the study were to assess the proportion of strandings by taxon and whether there were seasonal effects on abundance of stranded marine fauna. The study location was assessed opportunistically by trained observers who recorded and identified every stranded marine animal to the highest taxonomic degree possible. Stranded specimens of seabirds and marine mammals were grouped into overarching taxa of coastal and oceanic seabirds, and cetaceans and carnivorans. A principal component analysis (PCA) to visualize the association among stranded taxa registered along the study period and sea surface temperature anomalies using the Oceanic El Niño Index (ONI 3.4) and El Niño Coastal Index (ICEN) indexes and a Kruskal-Wallis test were conducted to evaluate abundance differences among taxonomic groups, taxa strandings and seasons. A total of 17,827 carcasses were encountered, 92.4% was seabirds and 7.6% marine mammals. Differences in abundances were significant among coastal and oceanic seabirds and marine mammals. Significant differences among seasons for cormorants and boobies were also identified. Coastal seabirds and pinnipeds dominated the stranding counts. A massive mortality of cormorants and boobies was registered between June and July 2014 possibly due to a moderate El Niño event. These strandings provide valuable information that could help lay the groundwork for implementation of a stranding network and science-based management projects in southern Peru.
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Affiliation(s)
- Clara Ortiz-Alvarez
- José Galvez 780E, Lima, 15074, Peru.
- Carrera de Biología Marina, Universidad Científica del Sur, Lima, Peru.
| | - Chiara Guidino
- José Galvez 780E, Lima, 15074, Peru
- Carrera de Biología Marina, Universidad Científica del Sur, Lima, Peru
| | | | - Joanna Alfaro-Shigueto
- José Galvez 780E, Lima, 15074, Peru
- Carrera de Biología Marina, Universidad Científica del Sur, Lima, Peru
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Deathly Silent: Exploring the Global Lack of Data Relating to Stranded Cetacean Euthanasia. Animals (Basel) 2021; 11:ani11051460. [PMID: 34069749 PMCID: PMC8161157 DOI: 10.3390/ani11051460] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/31/2021] [Revised: 05/07/2021] [Accepted: 05/18/2021] [Indexed: 11/25/2022] Open
Abstract
Simple Summary Cetacean strandings are frequent in occurrence and are likely to become even more common globally because of the effects of escalating anthropogenic activities. Due to the compromised state of stranded animals, euthanasia is often recommended or required. However, current knowledge and implementation of euthanasia methods remain highly variable, with limited data on the practicalities and welfare impacts of procedures. This study sought to evaluate the available published data on cetacean euthanasia in order to highlight significant knowledge gaps and provide direction to improve the welfare of stranded cetaceans. Data from the peer-reviewed literature and published reports were analysed, and significant knowledge gaps highlighted. Two main euthanasia methods, chemical and ballistics, were reported, with few details provided on the specific application of these. Few data were available about time to death/insensibility, parameters commonly required to assess the welfare impacts of killing methods. Overall, the findings highlight the lack of available information on cetacean euthanasia and suggest avenues for future work to improve welfare through the use of appropriate methods and increased data collection. Abstract The compromised state of stranded cetaceans means that euthanasia is often required. However, current knowledge and implementation of euthanasia methods remain highly variable, with limited data on the practicalities and welfare impacts of procedures. This study evaluated the available published data on cetacean euthanasia, highlighting knowledge gaps and providing direction to improve stranded cetacean welfare. A total of 2147 peer-reviewed articles describing marine mammal euthanasia were examined. Of these 3.1% provided details on the method used, with 91% employing chemical methods. Two countries, the United Kingdom (UK) and New Zealand (NZ), provided euthanasia reports to the International Whaling Commission (IWC) between 2007 and 2020. Methods employed were reported for 78.3% and 100% of individual cetaceans euthanised in the UK and NZ, respectively. In the UK, chemical euthanasia was most common (52%), whilst in NZ only ballistics methods were used. Few data were available about time to death/insensibility (TTD); 0.5% of peer-reviewed articles provided TTD, whilst TTD was reported for 35% of individuals in the UK and for 98% in NZ. However, IWC reports lacked detail on how death/insensibility were assessed, with multiple individuals “presumed instantly” killed. Overall, the findings highlight the lack of available information on cetacean euthanasia, and suggest increased data collection and the application of appropriate methods to improve welfare.
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Caruso F, Hickmott L, Warren JD, Segre P, Chiang G, Bahamonde P, Español-Jiménez S, Li S, Bocconcelli A. Diel differences in blue whale (Balaenoptera musculus) dive behavior increase nighttime risk of ship strikes in northern Chilean Patagonia. Integr Zool 2020; 16:594-611. [PMID: 33166068 PMCID: PMC9290343 DOI: 10.1111/1749-4877.12501] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
The northern Chilean Patagonia region is a key feeding ground and a nursing habitat in the southern hemisphere for blue whales (Balaenoptera musculus). From 2014 to 2019, during 6 separate research cruises, the dive behavior of 28 individual blue whales was investigated using bio‐logging tags (DTAGs), generating ≈190 h of data. Whales dove to significantly greater depths during the day compared to nighttime (day: 32.6 ± 18.7 m; night: 6.2 ± 2.7 m; P < 0.01). During the night, most time was spent close to the surface (86% ± 9.4%; P < 0.01) and at depths of less than 12 m. From 2016 to 2019, active acoustics (scientific echosounders) were used to record prey (euphausiids) density and distribution simultaneously with whale diving data. Tagged whales appeared to perform dives relative to the vertical migration of prey during the day. The association between diurnal prey migration and shallow nighttime dive behavior suggests that blue whales are at increased risk of ship collisions during periods of darkness since the estimated maximum ship draft of vessels operating in the region is also ≈12 m. In recent decades, northern Chilean Patagonia has seen a large increase in marine traffic due to a boom in salmon aquaculture and the passenger ship industry. Vessel strike risks for large whales are likely underestimated in this region. Results reported in this study may be valuable for policy and mitigation decisions regarding conservation of the endangered blue whale.
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Affiliation(s)
- Francesco Caruso
- Marine Mammals and Marine Bioacoustics Laboratory, Institute of Deep-sea Science and Engineering, Chinese Academy of Sciences (CAS), Sanya, China.,Woods Hole Oceanographic Institution, Woods Hole, Massachusetts, USA
| | - Leigh Hickmott
- Open Ocean Consulting, Hampshire, UK.,Scottish Oceans Institute, University of St Andrews, St Andrews, UK
| | | | - Paolo Segre
- Hopkins Marine Station, Stanford University, Pacific Grove, California, USA
| | - Gustavo Chiang
- Melimoyu Ecosystem Research Institute, Santiago de Chile, Chile
| | - Paulina Bahamonde
- Melimoyu Ecosystem Research Institute, Santiago de Chile, Chile.,HUB Ambiental-Centro de Estudios Avanzado, Universidad de Playa Ancha (UPLA), Valparaíso, Chile
| | | | - Songhai Li
- Marine Mammals and Marine Bioacoustics Laboratory, Institute of Deep-sea Science and Engineering, Chinese Academy of Sciences (CAS), Sanya, China
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