J. C. Mangel, S. Pingo, A. Jimenez, P. D. Doherty, J. Alfaro-Shigueto
ABSTRACT: The subpopulation of leatherback turtles Dermochelys coriacea in the eastern Pacific Ocean is classified as Critically Endangered due to multiple anthropogenic threats, the most urgent of which remains mortality at sea from fisheries interactions. Here we used satellite telemetry to assess the post-capture movements of leatherbacks in foraging grounds off Peru and attempt to evaluate post-release mortality. The 16 turtles tracked were bycatch from small-scale driftnet fishing vessels from the Peruvian ports of San Jose, Salaverry, and Parachique between 2014 and 2018. Sampled individuals included juveniles, subadults, and adults (curved carapace length range: 100.0 to 150.0 cm). Post-release overlap with driftnet fishing grounds was low and, upon release, all but one leatherback tracked for >30 d (n = 10) moved offshore beyond the continental shelf. From the subset of 6 tags with dive data, turtles spent 39.1 ± 11.8% of their time (range: 27.5 to 55.9%) within 10 m of the surface. Turtles spent significantly more time conducting shallow dives compared to deep dives during the day and night, carried out significantly more shallow dives compared to deep dives during the day and night, and carried out significantly more shallow dives during the day compared to night. Of the 16 tracks, biofouling (n = 3) and turtle injury or death (n = 3) were identified as the possible cause of tag cessation. Study results can inform ongoing population modeling and bycatch mitigation initiatives and efforts to predict and prevent bycatch interactions and mortality of this population.
{"title":"Post-release movements of leatherback turtles captured by the Peruvian small-scale driftnet fishery: insights from satellite telemetry","authors":"J. C. Mangel, S. Pingo, A. Jimenez, P. D. Doherty, J. Alfaro-Shigueto","doi":"10.3354/esr01343","DOIUrl":"https://doi.org/10.3354/esr01343","url":null,"abstract":"ABSTRACT: The subpopulation of leatherback turtles <i>Dermochelys coriacea</i> in the eastern Pacific Ocean is classified as Critically Endangered due to multiple anthropogenic threats, the most urgent of which remains mortality at sea from fisheries interactions. Here we used satellite telemetry to assess the post-capture movements of leatherbacks in foraging grounds off Peru and attempt to evaluate post-release mortality. The 16 turtles tracked were bycatch from small-scale driftnet fishing vessels from the Peruvian ports of San Jose, Salaverry, and Parachique between 2014 and 2018. Sampled individuals included juveniles, subadults, and adults (curved carapace length range: 100.0 to 150.0 cm). Post-release overlap with driftnet fishing grounds was low and, upon release, all but one leatherback tracked for >30 d (n = 10) moved offshore beyond the continental shelf. From the subset of 6 tags with dive data, turtles spent 39.1 ± 11.8% of their time (range: 27.5 to 55.9%) within 10 m of the surface. Turtles spent significantly more time conducting shallow dives compared to deep dives during the day and night, carried out significantly more shallow dives compared to deep dives during the day and night, and carried out significantly more shallow dives during the day compared to night. Of the 16 tracks, biofouling (n = 3) and turtle injury or death (n = 3) were identified as the possible cause of tag cessation. Study results can inform ongoing population modeling and bycatch mitigation initiatives and efforts to predict and prevent bycatch interactions and mortality of this population.","PeriodicalId":48746,"journal":{"name":"Endangered Species Research","volume":null,"pages":null},"PeriodicalIF":3.1,"publicationDate":"2024-06-27","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141517964","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"环境科学与生态学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Yu-Jia Lin, Hua Hsun Hsu, Zahid Nazeer, Premlal Panickan, Rommel H. Maneja, Diego Lozano-Cortés, Ali Qasem, Antonio Delgado Huertas, Lotfi Jilani Rabaoui
ABSTRACT: The great hammerhead shark Sphyrna mokarran and the scalloped hammerhead shark S. lewini are marine top predators with global distributions. However, limited information is available on the trophic ecology of hammerhead sharks in the Indian Ocean. In this study, we measured stable nitrogen and carbon isotopes in the muscle tissues of neonates and juveniles of S. mokarran and S. lewini from the waters of the western Arabian Gulf. In general, values of δ15N were lower in S. mokarran (10.8-18.7‰) than in S. lewini (12.2-18.7‰), indicating a reliance on food sources with low nitrogen values. Isotopic niche similarities were observed between female and male S. mokarran. We further observed considerable ontogenetic changes in the δ15N values of both S. mokarran and S. lewini neonates (a reduction from 19 to 12‰), reflecting the maternal effect. The effects of total length and sex on the nitrogen and stable isotope values were nonsignificant in S. mokarran juveniles. The western Arabian Gulf likely serves as a key feeding ground for both the neonates and the juveniles of S. mokarran. By contrast, S. lewini appears to have a low level of reliance on this region.
摘要：大双髻鲨（Sphyrna mokarran）和扇髻鲨（S. lewini）是分布于全球的海洋顶级掠食者。然而，有关印度洋双髻鲨营养生态学的信息非常有限。在这项研究中，我们测量了来自阿拉伯湾西部水域的 S. mokarran 和 S. lewini 新生和幼鱼肌肉组织中的稳定氮和碳同位素。一般来说，S. mokarran的δ15N值（10.8-18.7‰）低于S. lewini的δ15N值（12.2-18.7‰），表明其对低氮食物来源的依赖。雌性和雄性 S. mokarran 的同位素生态位相似。我们进一步观察到，S. mokarran和S. lewini新生幼体的δ15N值在发育过程中发生了很大变化（从19‰降至12‰），这反映了母体效应。在 S. mokarran 幼体中，总长度和性别对氮和稳定同位素值的影响不显著。阿拉伯湾西部可能是S. mokarran新生幼体的主要觅食地。相比之下，S. lewini 似乎对这一地区的依赖程度较低。
{"title":"Resource use by Sphyrna mokarran and S. lewini (Chondrichthyes) neonates and juveniles in the western Arabian Gulf: a stable isotope analysis","authors":"Yu-Jia Lin, Hua Hsun Hsu, Zahid Nazeer, Premlal Panickan, Rommel H. Maneja, Diego Lozano-Cortés, Ali Qasem, Antonio Delgado Huertas, Lotfi Jilani Rabaoui","doi":"10.3354/esr01341","DOIUrl":"https://doi.org/10.3354/esr01341","url":null,"abstract":"ABSTRACT: The great hammerhead shark <i>Sphyrna mokarran</i> and the scalloped hammerhead shark <i>S. lewini</i> are marine top predators with global distributions. However, limited information is available on the trophic ecology of hammerhead sharks in the Indian Ocean. In this study, we measured stable nitrogen and carbon isotopes in the muscle tissues of neonates and juveniles of <i>S. mokarran</i> and <i>S. lewini</i> from the waters of the western Arabian Gulf. In general, values of δ<sup>15</sup>N were lower in <i>S. mokarran</i> (10.8-18.7‰) than in <i>S. lewini</i> (12.2-18.7‰), indicating a reliance on food sources with low nitrogen values. Isotopic niche similarities were observed between female and male <i>S. mokarran</i>. We further observed considerable ontogenetic changes in the δ<sup>15</sup>N values of both <i>S. mokarran</i> and <i>S. lewini</i> neonates (a reduction from 19 to 12‰), reflecting the maternal effect. The effects of total length and sex on the nitrogen and stable isotope values were nonsignificant in <i>S. mokarran</i> juveniles. The western Arabian Gulf likely serves as a key feeding ground for both the neonates and the juveniles of <i>S. mokarran</i>. By contrast, <i>S. lewini</i> appears to have a low level of reliance on this region.","PeriodicalId":48746,"journal":{"name":"Endangered Species Research","volume":null,"pages":null},"PeriodicalIF":3.1,"publicationDate":"2024-06-27","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141507390","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"环境科学与生态学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Loren McClenachan, Torben Rick, Ruth H. Thurstan, Andrew Trant, Peter S. Alagona, Heidi K. Alleway, Chelsey Armstrong, Rebecca Bliege Bird, Nadia T. Rubio-Cisneros, Miguel Clavero, André C. Colonese, Katie Cramer, Ancilleno O. Davis, Joshua Drew, Michelle M. Early-Capistrán, Graciela Gil-Romera, Molly Grace, Marco B. A. Hatch, Eric Higgs, Kira Hoffman, Jeremy B. C. Jackson, Antonieta Jerardino, Michelle J. LeFebvre, Heike K. Lotze, Ryan S. Mohammed, Naia Morueta-Holme, Catalina Munteanu, Alexis M. Mychajliw, Bonnie Newsom, Aaron ODea, Daniel Pauly, Péter Szabó, Jimena Torres, John Waldman, Catherine West, Liqiang Xu, Hirokazu Yasuoka, Philine S. E. zu Ermgassen, Kyle S. Van Houtan
ABSTRACT: Historical ecology draws on a broad range of information sources and methods to provide insight into ecological and social change, especially over the past ∼12000 yr. While its results are often relevant to conservation and restoration, insights from its diverse disciplines, environments, and geographies have frequently remained siloed or underrepresented, restricting their full potential. Here, scholars and practitioners working in marine, freshwater, and terrestrial environments on 6 continents and various archipelagoes synthesize knowledge from the fields of history, anthropology, paleontology, and ecology with the goal of describing global research priorities for historical ecology to influence conservation. We used a structured decision-making process to identify and address questions in 4 key priority areas: (1) methods and concepts, (2) knowledge co-production and community engagement, (3) policy and management, and (4) climate change impacts. This work highlights the ways that historical ecology has developed and matured in its use of novel information sources, efforts to move beyond extractive research practices and toward knowledge co-production, and application to management challenges including climate change. We demonstrate the ways that this field has brought together researchers across disciplines, connected academics to practitioners, and engaged communities to create and apply knowledge of the past to address the challenges of our shared future.
{"title":"Global research priorities for historical ecology to inform conservation","authors":"Loren McClenachan, Torben Rick, Ruth H. Thurstan, Andrew Trant, Peter S. Alagona, Heidi K. Alleway, Chelsey Armstrong, Rebecca Bliege Bird, Nadia T. Rubio-Cisneros, Miguel Clavero, André C. Colonese, Katie Cramer, Ancilleno O. Davis, Joshua Drew, Michelle M. Early-Capistrán, Graciela Gil-Romera, Molly Grace, Marco B. A. Hatch, Eric Higgs, Kira Hoffman, Jeremy B. C. Jackson, Antonieta Jerardino, Michelle J. LeFebvre, Heike K. Lotze, Ryan S. Mohammed, Naia Morueta-Holme, Catalina Munteanu, Alexis M. Mychajliw, Bonnie Newsom, Aaron ODea, Daniel Pauly, Péter Szabó, Jimena Torres, John Waldman, Catherine West, Liqiang Xu, Hirokazu Yasuoka, Philine S. E. zu Ermgassen, Kyle S. Van Houtan","doi":"10.3354/esr01338","DOIUrl":"https://doi.org/10.3354/esr01338","url":null,"abstract":"ABSTRACT: Historical ecology draws on a broad range of information sources and methods to provide insight into ecological and social change, especially over the past ∼12000 yr. While its results are often relevant to conservation and restoration, insights from its diverse disciplines, environments, and geographies have frequently remained siloed or underrepresented, restricting their full potential. Here, scholars and practitioners working in marine, freshwater, and terrestrial environments on 6 continents and various archipelagoes synthesize knowledge from the fields of history, anthropology, paleontology, and ecology with the goal of describing global research priorities for historical ecology to influence conservation. We used a structured decision-making process to identify and address questions in 4 key priority areas: (1) methods and concepts, (2) knowledge co-production and community engagement, (3) policy and management, and (4) climate change impacts. This work highlights the ways that historical ecology has developed and matured in its use of novel information sources, efforts to move beyond extractive research practices and toward knowledge co-production, and application to management challenges including climate change. We demonstrate the ways that this field has brought together researchers across disciplines, connected academics to practitioners, and engaged communities to create and apply knowledge of the past to address the challenges of our shared future.","PeriodicalId":48746,"journal":{"name":"Endangered Species Research","volume":null,"pages":null},"PeriodicalIF":3.1,"publicationDate":"2024-06-27","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141507391","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"环境科学与生态学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
ABSTRACT: The European sturgeon Acipenser sturio has been of substantial commercial interest in the past. Today it is considered Critically Endangered, with only one remaining population in Europe. Fulfilling national conservation strategies and aiming for the conservation of biological diversity, Germany has released European sturgeons into their former habitats (Elbe River and its tributaries) as part of experimental measures to restore the population. However, little is known about their biology, sensitivity of life-stages to threats or trophic interactions within their former habitats. Here, we report on the first known predation of reintroduced sturgeons by harbor porpoises Phocoena phocoena and discuss predator-prey interactions in the light of sturgeon conservation. Stomach content analysis on stranded harbor porpoises revealed remains (scutes; modified ganoid scales) of European sturgeon in stomachs of 2 adult harbor porpoises (1.23%). Mean ± SD back-calculated lengths of ingested sturgeons were 26.11 ± 1.90 and 26.49 ± 1.93 cm, respectively, based on dorsal scute morphometrics. To date, no predator-prey interactions between sturgeons and harbor porpoises have been recorded in the North Sea. Future research into the diet of aquatic top predators with overlapping habitats at stocking sites of European sturgeons, transcending national boundaries, will uncover possible conservation concerns, conflicts of species-specific management interests and reintroduction success of European sturgeons.
{"title":"First record of a Critically Endangered species, European sturgeon, in the stomach of harbor porpoises from the North Sea","authors":"Eileen Heße, Jörn Gessner, Ursula Siebert, Anita Gilles","doi":"10.3354/esr01342","DOIUrl":"https://doi.org/10.3354/esr01342","url":null,"abstract":"ABSTRACT: The European sturgeon <i>Acipenser sturio</i> has been of substantial commercial interest in the past. Today it is considered Critically Endangered, with only one remaining population in Europe. Fulfilling national conservation strategies and aiming for the conservation of biological diversity, Germany has released European sturgeons into their former habitats (Elbe River and its tributaries) as part of experimental measures to restore the population. However, little is known about their biology, sensitivity of life-stages to threats or trophic interactions within their former habitats. Here, we report on the first known predation of reintroduced sturgeons by harbor porpoises <i>Phocoena phocoena</i> and discuss predator-prey interactions in the light of sturgeon conservation. Stomach content analysis on stranded harbor porpoises revealed remains (scutes; modified ganoid scales) of European sturgeon in stomachs of 2 adult harbor porpoises (1.23%). Mean ± SD back-calculated lengths of ingested sturgeons were 26.11 ± 1.90 and 26.49 ± 1.93 cm, respectively, based on dorsal scute morphometrics. To date, no predator-prey interactions between sturgeons and harbor porpoises have been recorded in the North Sea. Future research into the diet of aquatic top predators with overlapping habitats at stocking sites of European sturgeons, transcending national boundaries, will uncover possible conservation concerns, conflicts of species-specific management interests and reintroduction success of European sturgeons.","PeriodicalId":48746,"journal":{"name":"Endangered Species Research","volume":null,"pages":null},"PeriodicalIF":3.1,"publicationDate":"2024-06-27","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141517966","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"环境科学与生态学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Kirby Parnell, Karlina Merkens, Chloé Huetz, Isabelle Charrier, Stacie J. Robinson, Aude Pacini, Lars Bejder
ABSTRACT: Studying underwater soundscapes of critical habitats of marine mammals can provide valuable information on the acoustic environment utilized by sound-reliant animals. For the endangered Hawaiian monk seal Neomonachus schauinslandi (HMS), the acoustic scene of their aquatic habitats is poorly understood. We measured ambient noise levels and characterized sound sources at 4 shallow critical habitats of the HMS. Broadband levels ranged from 107.8-123.4 dB re 1 µPa. Octave band levels showed diel patterns associated with biological and anthropogenic sources that mask HMS vocalizations. Biological sources dominated the soundscape at all sites. We opportunistically recorded 2 large-scale geophonic events: Hurricane Douglas (Category 4) and a 6.2 magnitude earthquake. This study provides the first description of underwater soundscapes at critical habitats of the HMS across its expansive range. These measurements serve as a baseline for future studies to understand the impacts of human activities on underwater soundscapes.
摘要：对海洋哺乳动物重要栖息地的水下声景进行研究，可以提供有关依赖声音的动物所利用的声学环境的宝贵信息。对于濒危的夏威夷僧海豹（Neomonachus schauinslandi，HMS）来说，人们对其水生栖息地的声学环境知之甚少。我们在夏威夷僧海豹的 4 个浅水关键栖息地测量了环境噪声水平并描述了声源特征。宽带声级范围为 107.8-123.4 dB re 1 µPa。倍频程声级显示出与掩盖马氏海马发声的生物和人为声源相关的昼夜模式。生物声源在所有地点都占主导地位。我们随机记录了 2 次大规模地声事件：道格拉斯飓风（4 级）和 6.2 级地震。这项研究首次描述了海马在其广阔分布区的重要栖息地的水下声景。这些测量结果可作为未来研究的基线，以了解人类活动对水下声景的影响。
{"title":"Underwater soundscapes within critical habitats of the endangered Hawaiian monk seal: implications for conservation","authors":"Kirby Parnell, Karlina Merkens, Chloé Huetz, Isabelle Charrier, Stacie J. Robinson, Aude Pacini, Lars Bejder","doi":"10.3354/esr01336","DOIUrl":"https://doi.org/10.3354/esr01336","url":null,"abstract":"ABSTRACT: Studying underwater soundscapes of critical habitats of marine mammals can provide valuable information on the acoustic environment utilized by sound-reliant animals. For the endangered Hawaiian monk seal <i>Neomonachus schauinslandi</i> (HMS), the acoustic scene of their aquatic habitats is poorly understood. We measured ambient noise levels and characterized sound sources at 4 shallow critical habitats of the HMS. Broadband levels ranged from 107.8-123.4 dB re 1 µPa. Octave band levels showed diel patterns associated with biological and anthropogenic sources that mask HMS vocalizations. Biological sources dominated the soundscape at all sites. We opportunistically recorded 2 large-scale geophonic events: Hurricane Douglas (Category 4) and a 6.2 magnitude earthquake. This study provides the first description of underwater soundscapes at critical habitats of the HMS across its expansive range. These measurements serve as a baseline for future studies to understand the impacts of human activities on underwater soundscapes.","PeriodicalId":48746,"journal":{"name":"Endangered Species Research","volume":null,"pages":null},"PeriodicalIF":3.1,"publicationDate":"2024-06-27","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141529486","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"环境科学与生态学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Glenn D. Goodwin, Kristen M. Hart, Abby C. Evans, Derek A. Burkholder
ABSTRACT: Developing conservation strategies for highly migratory marine species relies on understanding their spatial distributions. Nesting populations of female loggerhead (Caretta caretta) turtles typically travel from widely dispersed foraging areas and make use of common internesting areas between nesting events. Protection of these areas is essential to the conservation of this species. In this study, we used satellite tracking and behavioral switching state-space movement modeling to examine the internesting use-areas, migration patterns, and foraging area distribution of a previously uninvestigated nesting loggerhead population in southeast Florida. While these turtles spent much of their internesting period close to their nesting site, only 17.4% of the identified internesting area is within the boundaries currently designated under the US Endangered Species Act as critical loggerhead ‘nearshore reproductive habitat’. Additionally, 72% of turtles in this study (17 of 21) that were tracked to foraging grounds have foraging home ranges outside of the USA, with 62% of turtles (n = 13) in The Bahamas. Considering the proximity of their internesting areas to a large human population center and their largely international foraging distribution, this population could benefit from expanding federally designated critical habitat, along with developing collaborative conservation strategies between the USA and The Bahamas.
{"title":"Satellite telemetry reveals high-use internesting areas and international foraging extent for loggerhead turtles tagged in southeast Florida, USA","authors":"Glenn D. Goodwin, Kristen M. Hart, Abby C. Evans, Derek A. Burkholder","doi":"10.3354/esr01339","DOIUrl":"https://doi.org/10.3354/esr01339","url":null,"abstract":"ABSTRACT: Developing conservation strategies for highly migratory marine species relies on understanding their spatial distributions. Nesting populations of female loggerhead (<i>Caretta caretta</i>) turtles typically travel from widely dispersed foraging areas and make use of common internesting areas between nesting events. Protection of these areas is essential to the conservation of this species. In this study, we used satellite tracking and behavioral switching state-space movement modeling to examine the internesting use-areas, migration patterns, and foraging area distribution of a previously uninvestigated nesting loggerhead population in southeast Florida. While these turtles spent much of their internesting period close to their nesting site, only 17.4% of the identified internesting area is within the boundaries currently designated under the US Endangered Species Act as critical loggerhead ‘nearshore reproductive habitat’. Additionally, 72% of turtles in this study (17 of 21) that were tracked to foraging grounds have foraging home ranges outside of the USA, with 62% of turtles (n = 13) in The Bahamas. Considering the proximity of their internesting areas to a large human population center and their largely international foraging distribution, this population could benefit from expanding federally designated critical habitat, along with developing collaborative conservation strategies between the USA and The Bahamas.","PeriodicalId":48746,"journal":{"name":"Endangered Species Research","volume":null,"pages":null},"PeriodicalIF":3.1,"publicationDate":"2024-06-27","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141517965","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"环境科学与生态学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Michelle Perez, Col Limpus, Takahiro Shimada, Saskia McDonald, Owen Coffee, Eve Hinchliffe, Mark Hamann
ABSTRACT: Understanding green turtle habitat use during the nesting season is important for informing management decisions relating to green turtles and ecosystems that support them. Despite patterns such as migration being described, few studies investigate behaviour during the inter-nesting period. This research aims to describe and quantify the spatial distribution patterns of green turtles during 2 nesting seasons on Raine Island in the northern Great Barrier Reef. Satellite telemetry data were used to analyse the inter-nesting movements and patterns of green turtles in 2017 (n = 19) and 2018 (n = 20). The inter-nesting period ranged from 51 to 100 d (76.33 ± 15.98 d) across both seasons. The average inter-nesting area of individual turtles did not differ between nesting seasons (2017: 12.31 ± 13.22 km2, 2018: 12.01 ± 21.92 km2). In addition, it was established that 39 individuals are a sufficient sample size to describe the spatial distribution. Approximately half of the tracked individuals remained at the same reef for their entire inter-nesting season (n = 19), and half used habitat on nearby reefs (n = 20). Most turtles showed fidelity to Raine Island as a nesting site (n = 37), laying all their clutches on the island. However, 2 individuals travelled 479 and 337 km during the inter-nesting period. This study thus highlights where the habitats used by green turtles during the inter-nesting season are and how they are used. Therefore, management strategies and conservation decisions can be informed to maintain the viability of these essential habitats.
{"title":"Inter-nesting habitat use by green turtles Chelonia mydas in the Great Barrier Reef","authors":"Michelle Perez, Col Limpus, Takahiro Shimada, Saskia McDonald, Owen Coffee, Eve Hinchliffe, Mark Hamann","doi":"10.3354/esr01340","DOIUrl":"https://doi.org/10.3354/esr01340","url":null,"abstract":"ABSTRACT: Understanding green turtle habitat use during the nesting season is important for informing management decisions relating to green turtles and ecosystems that support them. Despite patterns such as migration being described, few studies investigate behaviour during the inter-nesting period. This research aims to describe and quantify the spatial distribution patterns of green turtles during 2 nesting seasons on Raine Island in the northern Great Barrier Reef. Satellite telemetry data were used to analyse the inter-nesting movements and patterns of green turtles in 2017 (n = 19) and 2018 (n = 20). The inter-nesting period ranged from 51 to 100 d (76.33 ± 15.98 d) across both seasons. The average inter-nesting area of individual turtles did not differ between nesting seasons (2017: 12.31 ± 13.22 km<sup>2</sup>, 2018: 12.01 ± 21.92 km<sup>2</sup>). In addition, it was established that 39 individuals are a sufficient sample size to describe the spatial distribution. Approximately half of the tracked individuals remained at the same reef for their entire inter-nesting season (n = 19), and half used habitat on nearby reefs (n = 20). Most turtles showed fidelity to Raine Island as a nesting site (n = 37), laying all their clutches on the island. However, 2 individuals travelled 479 and 337 km during the inter-nesting period. This study thus highlights where the habitats used by green turtles during the inter-nesting season are and how they are used. Therefore, management strategies and conservation decisions can be informed to maintain the viability of these essential habitats.","PeriodicalId":48746,"journal":{"name":"Endangered Species Research","volume":null,"pages":null},"PeriodicalIF":3.1,"publicationDate":"2024-06-27","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141517967","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"环境科学与生态学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Andrew J. Wright, Joaquin Gabaldon, Ding Zhang, Philip Hamilton
ABSTRACT: Critically endangered North Atlantic right whales Eubalaena glacialis have recently shifted their summer distribution from the Bay of Fundy to the Gulf of St. Lawrence (GSL), Canada. Entanglement in fishing gear and vessel strikes remain the main lethal threats. Foraging on deep aggregations of Calanus prey in the Bay of Fundy involves stereotyped deep ‘flat-bottom’ (U-shaped) dives, while foraging on sub-surface Calanus aggregations on the winter feeding grounds of Cape Cod Bay involves surface feeding. To explore North Atlantic right whale feeding behaviour in the GSL, 5 acoustic and biologging tags (DTAGs) were deployed using suction cups in 2019 and 2020. One whale knocked off the tag after 14 min. Diving behaviour of the other 4 whales with 2.0 to 4.7 h of data was mostly split between flat-bottom foraging dives at, or very close to, the sea floor, and near-surface activities, including logging, respirations, and potentially also sleeping. This biphasic vertical distribution not only places the whales at risk of being hit by vessels, but it may also put them at risk of coming into contact with groundlines used in various fishing industries in the GSL. Although additional research is needed as this limited dataset was restricted to hours of daylight, these results provide new information about right whale behaviour in the GSL that can help inform management actions to reduce human impacts on this endangered species.
{"title":"Bimodal vertical distribution of right whales Eubalaena glacialis in the Gulf of St. Lawrence","authors":"Andrew J. Wright, Joaquin Gabaldon, Ding Zhang, Philip Hamilton","doi":"10.3354/esr01330","DOIUrl":"https://doi.org/10.3354/esr01330","url":null,"abstract":"ABSTRACT: Critically endangered North Atlantic right whales <i>Eubalaena glacialis</i> have recently shifted their summer distribution from the Bay of Fundy to the Gulf of St. Lawrence (GSL), Canada. Entanglement in fishing gear and vessel strikes remain the main lethal threats. Foraging on deep aggregations of <i>Calanus</i> prey in the Bay of Fundy involves stereotyped deep ‘flat-bottom’ (U-shaped) dives, while foraging on sub-surface <i>Calanus</i> aggregations on the winter feeding grounds of Cape Cod Bay involves surface feeding. To explore North Atlantic right whale feeding behaviour in the GSL, 5 acoustic and biologging tags (DTAGs) were deployed using suction cups in 2019 and 2020. One whale knocked off the tag after 14 min. Diving behaviour of the other 4 whales with 2.0 to 4.7 h of data was mostly split between flat-bottom foraging dives at, or very close to, the sea floor, and near-surface activities, including logging, respirations, and potentially also sleeping. This biphasic vertical distribution not only places the whales at risk of being hit by vessels, but it may also put them at risk of coming into contact with groundlines used in various fishing industries in the GSL. Although additional research is needed as this limited dataset was restricted to hours of daylight, these results provide new information about right whale behaviour in the GSL that can help inform management actions to reduce human impacts on this endangered species.","PeriodicalId":48746,"journal":{"name":"Endangered Species Research","volume":null,"pages":null},"PeriodicalIF":3.1,"publicationDate":"2024-06-13","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141517968","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"环境科学与生态学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
K. L. Indeck, R. Gehrmann, A. L. Richardson, D. Barclay, M. F. Baumgartner, V. Nolet, K. T. A. Davies
ABSTRACT: Passive acoustic monitoring has become an integral tool for determining the presence, distribution, and behavior of vocally active cetacean species. Acoustically equipped underwater gliders are becoming a routine monitoring platform, because they can cover large spatial scales during a single deployment and have the capability to relay data to shore in near real-time. Yet, more research is needed to determine what information can be derived from glider-recorded cetacean detections. Here, a Slocum glider that monitored continuously for low frequency (<1 kHz) baleen whale vocalizations was deployed across the Honguedo Strait and the associated traffic separation scheme in the Gulf of St. Lawrence, Canada, during September and October 2019. We conducted a manual analysis of the archived audio to examine spatial and temporal variation in acoustic detection rates of North Atlantic right whales (NARWs), blue whales, and fin whales. Call detections of blue and fin whales demonstrated that both species were acoustically active throughout the deployment. Environmental association models suggested their preferential use of foraging areas along the southern slopes of the Laurentian Channel. Results also indicate that elevated background noise levels in the shipping lanes from vessel traffic only minimally influenced the likelihood of detecting blue whale acoustic presence, while they did not affect fin whale detectability. NARWs were definitively detected on less than 20% of deployment days, so only qualitative assessments of their presence were described. Nevertheless, detections of all 3 species highlight that their movements throughout this seasonally important region overlap with a high volume of vessel traffic, increasing their risk of ship strike.
{"title":"Variation in glider-detected North Atlantic right, blue, and fin whale calls in proximity to high-traffic shipping lanes","authors":"K. L. Indeck, R. Gehrmann, A. L. Richardson, D. Barclay, M. F. Baumgartner, V. Nolet, K. T. A. Davies","doi":"10.3354/esr01327","DOIUrl":"https://doi.org/10.3354/esr01327","url":null,"abstract":"ABSTRACT: Passive acoustic monitoring has become an integral tool for determining the presence, distribution, and behavior of vocally active cetacean species. Acoustically equipped underwater gliders are becoming a routine monitoring platform, because they can cover large spatial scales during a single deployment and have the capability to relay data to shore in near real-time. Yet, more research is needed to determine what information can be derived from glider-recorded cetacean detections. Here, a Slocum glider that monitored continuously for low frequency (<1 kHz) baleen whale vocalizations was deployed across the Honguedo Strait and the associated traffic separation scheme in the Gulf of St. Lawrence, Canada, during September and October 2019. We conducted a manual analysis of the archived audio to examine spatial and temporal variation in acoustic detection rates of North Atlantic right whales (NARWs), blue whales, and fin whales. Call detections of blue and fin whales demonstrated that both species were acoustically active throughout the deployment. Environmental association models suggested their preferential use of foraging areas along the southern slopes of the Laurentian Channel. Results also indicate that elevated background noise levels in the shipping lanes from vessel traffic only minimally influenced the likelihood of detecting blue whale acoustic presence, while they did not affect fin whale detectability. NARWs were definitively detected on less than 20% of deployment days, so only qualitative assessments of their presence were described. Nevertheless, detections of all 3 species highlight that their movements throughout this seasonally important region overlap with a high volume of vessel traffic, increasing their risk of ship strike.","PeriodicalId":48746,"journal":{"name":"Endangered Species Research","volume":null,"pages":null},"PeriodicalIF":3.1,"publicationDate":"2024-06-13","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141529487","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"环境科学与生态学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Samantha Hoff, Brittany A. Mosher, Mandy Watson, Luanne Johnson, Elizabeth Olson, Danielle ODell, Casey J. Pendergast, Daniel A. Bogan, Carl J. Herzog, Wendy C. Turner
ABSTRACT: Northern myotis Myotis septentrionalis are one of the bat species most affected by white-nose syndrome (WNS), and disease-induced declines may cause compounding effects when combined with other threats such as habitat loss and fragmentation. Recent evidence suggests that peripheral populations are persisting in post-WNS years; however, the environmental factors that influence the occurrence of this species along the Atlantic Coastal Plain are virtually unknown. We conducted a large-scale acoustic survey on 3 islands: Long Island, New York, and Martha’s Vineyard and Nantucket, Massachusetts, USA, and used a multi-scale occupancy modeling approach to determine the landscape and abiotic factors affecting the distribution of northern myotis. Our estimates of occupancy and detection probability suggest widespread presence across the islands. At the local (200 m) scale, we identified strong negative effects of development on Long Island and Nantucket and a strong positive effect of forest habitat on Martha’s Vineyard. None of the variables we measured sufficiently explained the landscape (1 km2) occupancy of this species, which was very high (ψ = 0.81-0.97), representing an outlier for this species in the post-WNS landscape. The lack of association at the landscape scale suggests that general differences in land cover are not a driving factor of higher occupancy of peripheral northern myotis populations, while local site-specific conditions may be supporting critical foraging or roosting habitat. Because islands are particularly vulnerable to human-driven habitat alteration due to the constraint of limited space, and development pressure is expected to increase, this study provides a baseline to enable managers to assess the effects of future environmental disturbances and monitor population trends to support long-term survival of northern myotis.
{"title":"Widespread occupancy of the endangered northern myotis on northeastern Atlantic Coastal Plain islands","authors":"Samantha Hoff, Brittany A. Mosher, Mandy Watson, Luanne Johnson, Elizabeth Olson, Danielle ODell, Casey J. Pendergast, Daniel A. Bogan, Carl J. Herzog, Wendy C. Turner","doi":"10.3354/esr01335","DOIUrl":"https://doi.org/10.3354/esr01335","url":null,"abstract":"ABSTRACT: Northern myotis <i>Myotis septentrionalis</i> are one of the bat species most affected by white-nose syndrome (WNS), and disease-induced declines may cause compounding effects when combined with other threats such as habitat loss and fragmentation. Recent evidence suggests that peripheral populations are persisting in post-WNS years; however, the environmental factors that influence the occurrence of this species along the Atlantic Coastal Plain are virtually unknown. We conducted a large-scale acoustic survey on 3 islands: Long Island, New York, and Martha’s Vineyard and Nantucket, Massachusetts, USA, and used a multi-scale occupancy modeling approach to determine the landscape and abiotic factors affecting the distribution of northern myotis. Our estimates of occupancy and detection probability suggest widespread presence across the islands. At the local (200 m) scale, we identified strong negative effects of development on Long Island and Nantucket and a strong positive effect of forest habitat on Martha’s Vineyard. None of the variables we measured sufficiently explained the landscape (1 km<sup>2</sup>) occupancy of this species, which was very high (ψ = 0.81-0.97), representing an outlier for this species in the post-WNS landscape. The lack of association at the landscape scale suggests that general differences in land cover are not a driving factor of higher occupancy of peripheral northern myotis populations, while local site-specific conditions may be supporting critical foraging or roosting habitat. Because islands are particularly vulnerable to human-driven habitat alteration due to the constraint of limited space, and development pressure is expected to increase, this study provides a baseline to enable managers to assess the effects of future environmental disturbances and monitor population trends to support long-term survival of northern myotis.","PeriodicalId":48746,"journal":{"name":"Endangered Species Research","volume":null,"pages":null},"PeriodicalIF":3.1,"publicationDate":"2024-06-13","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141517982","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"环境科学与生态学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
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