Michael D. Pointer, Hoby Tsimilajay, Sam Hyde Roberts, Jennifer A. Gill, Lewis G. Spurgin
ABSTRACT: The Critically Endangered day gecko Phelsuma antanosy is micro-endemic to 2 humid forest sites in southeastern Madagascar. At one of these, Sainte Luce, it inhabits 4 forest fragments, 2 of which are set to be cleared for mining. Translocation of individuals from within the mining path to protected forest fragments has been proposed to mitigate the impact of habitat loss and the resulting reduction in population size. However, lack of knowledge of its habitat requirements and population structure inhibits efforts to evaluate the likely ecological consequences of translocation. We sampled 92 P. antanosy individuals across each of the known subpopulations in Sainte Luce and assessed the habitat conditions in which they occur, alongside levels of morphological variation. Using 5 morphological trait measures, we found no evidence of subpopulation differentiation. Almost all (>87%) P. antanosy individuals were found on Pandanus longistylus plants and occupancy levels were higher in areas with moderate (30-60%) canopy cover and no other Phelsuma spp. present, suggesting that translocated individuals should be located into these conditions and within a short (<5 m) distance of P. longistylus plants. We propose that siting individuals in patches meeting these criteria may help to maximise translocation efficacy. We discuss our results in the context of the lack of ecological and genetic information on this species, the general need for long-term monitoring of threatened species and the utility of translocation projects to inform and benefit conservation science.
{"title":"Habitat use of the micro-endemic day gecko Phelsuma antanosy in Sainte Luce, Madagascar, and the case for translocation","authors":"Michael D. Pointer, Hoby Tsimilajay, Sam Hyde Roberts, Jennifer A. Gill, Lewis G. Spurgin","doi":"10.3354/esr01353","DOIUrl":"https://doi.org/10.3354/esr01353","url":null,"abstract":"ABSTRACT: The Critically Endangered day gecko <i>Phelsuma antanosy</i> is micro-endemic to 2 humid forest sites in southeastern Madagascar. At one of these, Sainte Luce, it inhabits 4 forest fragments, 2 of which are set to be cleared for mining. Translocation of individuals from within the mining path to protected forest fragments has been proposed to mitigate the impact of habitat loss and the resulting reduction in population size. However, lack of knowledge of its habitat requirements and population structure inhibits efforts to evaluate the likely ecological consequences of translocation. We sampled 92 <i>P. antanosy</i> individuals across each of the known subpopulations in Sainte Luce and assessed the habitat conditions in which they occur, alongside levels of morphological variation. Using 5 morphological trait measures, we found no evidence of subpopulation differentiation. Almost all (>87%) <i>P. antanosy</i> individuals were found on <i>Pandanus longistylus</i> plants and occupancy levels were higher in areas with moderate (30-60%) canopy cover and no other <i>Phelsuma</i> spp. present, suggesting that translocated individuals should be located into these conditions and within a short (<5 m) distance of <i>P. longistylus</i> plants. We propose that siting individuals in patches meeting these criteria may help to maximise translocation efficacy. We discuss our results in the context of the lack of ecological and genetic information on this species, the general need for long-term monitoring of threatened species and the utility of translocation projects to inform and benefit conservation science.","PeriodicalId":48746,"journal":{"name":"Endangered Species Research","volume":null,"pages":null},"PeriodicalIF":3.1,"publicationDate":"2024-08-29","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142194966","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}
Chiara Agabiti, Livia Tolve, Giulia Baldi, Marina Zucchini, Salvatore Tuccio, Federica Restelli, Daniela Freggi, Paolo Luschi, Paolo Casale
ABSTRACT: Knowledge of the distribution and density of marine species is key to understanding habitat use and interactions with human activities. Yet such information for sea turtles remains scarce, especially at foraging areas, where low turtle density represents an additional challenge in comparison to turtle aggregations at coastal breeding areas. Aerial surveys with aircraft are an efficient method for collecting these data over broad scales, while more novel unoccupied aerial vehicles (UAVs) are better suited for finer-scale data collection. However, their use is less developed, especially in offshore areas. Here we explored, for the first time in the Mediterranean, the potential of UAV surveys to estimate turtle density (surface and total) at foraging areas and its temporal trend. Between 2017 and 2023, we conducted 427 flights in the Pelagian Islands Archipelago (PIA), Italy, a regionally important foraging area of the loggerhead sea turtle Caretta caretta. To convert from surface to total density, we used data from multisensor biologgers deployed on 22 turtles to calculate the proportion of time turtles are visible from aerial surveys (availability time proportion, ATP). Results show that the mean surface turtle density in the PIA (0.336-0.477 turtles km-2) is among the highest reported globally for a loggerhead turtle foraging area. Such densities make it possible to assess population trends through periodic UAV surveys, which are less expensive than aircraft surveys and which can minimize the typical biases of aerial surveys (distance sampling, perception, and misidentification). A standardized methodology is needed for meaningful comparisons, including ATP at the visible depth layer vs. surface.
{"title":"Combining UAVs and multi-sensor dataloggers to estimate fine-scale sea turtle density at foraging areas: a case study in the central Mediterranean","authors":"Chiara Agabiti, Livia Tolve, Giulia Baldi, Marina Zucchini, Salvatore Tuccio, Federica Restelli, Daniela Freggi, Paolo Luschi, Paolo Casale","doi":"10.3354/esr01350","DOIUrl":"https://doi.org/10.3354/esr01350","url":null,"abstract":"ABSTRACT: Knowledge of the distribution and density of marine species is key to understanding habitat use and interactions with human activities. Yet such information for sea turtles remains scarce, especially at foraging areas, where low turtle density represents an additional challenge in comparison to turtle aggregations at coastal breeding areas. Aerial surveys with aircraft are an efficient method for collecting these data over broad scales, while more novel unoccupied aerial vehicles (UAVs) are better suited for finer-scale data collection. However, their use is less developed, especially in offshore areas. Here we explored, for the first time in the Mediterranean, the potential of UAV surveys to estimate turtle density (surface and total) at foraging areas and its temporal trend. Between 2017 and 2023, we conducted 427 flights in the Pelagian Islands Archipelago (PIA), Italy, a regionally important foraging area of the loggerhead sea turtle <i>Caretta caretta</i>. To convert from surface to total density, we used data from multisensor biologgers deployed on 22 turtles to calculate the proportion of time turtles are visible from aerial surveys (availability time proportion, ATP). Results show that the mean surface turtle density in the PIA (0.336-0.477 turtles km<sup>-2</sup>) is among the highest reported globally for a loggerhead turtle foraging area. Such densities make it possible to assess population trends through periodic UAV surveys, which are less expensive than aircraft surveys and which can minimize the typical biases of aerial surveys (distance sampling, perception, and misidentification). A standardized methodology is needed for meaningful comparisons, including ATP at the visible depth layer vs. surface.","PeriodicalId":48746,"journal":{"name":"Endangered Species Research","volume":null,"pages":null},"PeriodicalIF":3.1,"publicationDate":"2024-08-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142194969","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: North Pacific right whales Eubalaena japonica once numbered in the 10s of 1000s. Today, the eastern population is one of the most endangered large whale stocks in the world. A lack of dedicated surveys and a population in the 10s of animals have resulted in considerable knowledge gaps. Here, we collate all contemporary sightings of eastern North Pacific right whales (ENPRWs) from 2006 through 2023 to investigate possible migratory routes and elucidate important habitat. Sightings in the northern Bering Sea, Gulf of Alaska, and along the west coast of North America have increased. Of the 99 sightings recorded between 2006 and 2023, 58 occurred during the few dedicated ENPRW surveys with simultaneous aerial and vessel platforms. All animals sighted were non-calves. Opportunistic sightings along the California coast were only reported in spring months (February-May). While this timing would coincide with a northward migration from lower latitudes, poor photo quality prevented matching of these animals, making it difficult to determine migratory patterns. Furthermore, there have been no sightings in Hawai’i or Mexico since 1996, and no sightings in the eastern North Pacific off the continental shelf since the 1970s. To date, only 2 animals have been photographically matched from Alaska to more southerly latitudes, and there have been no photographic matches between the Bering Sea and the Gulf of Alaska. Feeding has been observed throughout their range, suggesting right whales opportunistically feed whenever possible. While their primary migratory destinations remain unknown, these recent sightings provide insight into important ENPRW habitat in Alaska.
{"title":"Contemporary sightings of eastern North Pacific right whales, 2006 to 2023","authors":"Jessica Crance, Amy Kennedy","doi":"10.3354/esr01349","DOIUrl":"https://doi.org/10.3354/esr01349","url":null,"abstract":"ABSTRACT: North Pacific right whales <i>Eubalaena japonica</i> once numbered in the 10s of 1000s. Today, the eastern population is one of the most endangered large whale stocks in the world. A lack of dedicated surveys and a population in the 10s of animals have resulted in considerable knowledge gaps. Here, we collate all contemporary sightings of eastern North Pacific right whales (ENPRWs) from 2006 through 2023 to investigate possible migratory routes and elucidate important habitat. Sightings in the northern Bering Sea, Gulf of Alaska, and along the west coast of North America have increased. Of the 99 sightings recorded between 2006 and 2023, 58 occurred during the few dedicated ENPRW surveys with simultaneous aerial and vessel platforms. All animals sighted were non-calves. Opportunistic sightings along the California coast were only reported in spring months (February-May). While this timing would coincide with a northward migration from lower latitudes, poor photo quality prevented matching of these animals, making it difficult to determine migratory patterns. Furthermore, there have been no sightings in Hawai’i or Mexico since 1996, and no sightings in the eastern North Pacific off the continental shelf since the 1970s. To date, only 2 animals have been photographically matched from Alaska to more southerly latitudes, and there have been no photographic matches between the Bering Sea and the Gulf of Alaska. Feeding has been observed throughout their range, suggesting right whales opportunistically feed whenever possible. While their primary migratory destinations remain unknown, these recent sightings provide insight into important ENPRW habitat in Alaska.","PeriodicalId":48746,"journal":{"name":"Endangered Species Research","volume":null,"pages":null},"PeriodicalIF":3.1,"publicationDate":"2024-08-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142194970","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}
Sophia N. Lyon, Joseph A. Tomoleoni, Julie L. Yee, Jessica A. Fujii, Nicole M. Thometz
ABSTRACT: Sea otters Enhydra lutris are vital keystone predators throughout the North Pacific that were nearly extirpated during the maritime fur trade. Recovery of southern sea otters E. l. nereis has proceeded slowly, with much of their historical range remaining unoccupied, resulting in reduced ecosystem functioning. Numerous studies have used foraging metrics to assess the population status of southern sea otters throughout their current range, but little is known about the northern range extent, where a stall in expansion has limited recovery. Thus, we collected census and foraging data of sea otters at Año Nuevo State Park, California, from 2019 to 2021 to determine sea otter abundance, diet composition, diet diversity, and average energy intake rate at the northern range edge. We then assessed regional population status by comparing values from Año Nuevo with previously collected data from other locations in California, including high-density, range center sites and low-density, range periphery sites. We found that sea otter density at Año Nuevo was greater than surrounding areas at the northern range periphery, and the average (±95% CI) energy intake (9.51 ± 0.91 kcal min-1) more closely resembled values observed at high-density sites. Further, dietary diversity (using the Shannon-Wiener index, H) was intermediate between previously studied high- and low-density populations (H = 1.81), with crabs making up the largest proportion of the diet (~56%). Overall, this study highlights possible effects of occupation time and range stagnation, identifies unique aspects of the prey resource base at Año Nuevo, and provides insight into the ongoing lack of northern range expansion.
ABSTRACT: 海獭（Enhydra lutris）是北太平洋地区重要的关键食肉动物，在海上毛皮贸易期间几乎灭绝。南部海獭（E. l. nereis）的恢复进展缓慢，其大部分历史分布区仍无人居住，导致生态系统功能减弱。许多研究利用觅食指标来评估南方海獭在其目前分布区的种群状况，但对其北部分布区的情况却知之甚少，因为北部分布区的扩张停滞限制了其恢复。因此，我们从 2019 年到 2021 年在加利福尼亚州 Año Nuevo 州立公园收集了海獭的普查和觅食数据，以确定北部分布区边缘的海獭丰度、食物组成、食物多样性和平均能量摄入率。然后，我们将 Año Nuevo 的数值与之前从加利福尼亚其他地点收集的数据（包括高密度、分布中心地点和低密度、分布边缘地点）进行比较，评估区域种群状况。我们发现，Año Nuevo 的海獭密度高于北部分布区外围的周边地区，平均（±95% CI）能量摄入量（9.51 ± 0.91 kcal min-1）更接近于在高密度地点观察到的数值。此外，膳食多样性（采用香农-维纳指数，H）介于先前研究的高密度和低密度种群之间（H = 1.81），螃蟹在膳食中所占比例最大（约 56%）。总之，这项研究强调了占领时间和分布区停滞可能造成的影响，确定了阿诺努埃沃猎物资源基础的独特方面，并为持续缺乏北部分布区扩张提供了见解。
{"title":"Foraging ecology of southern sea otters at the northern range extent informs regional population dynamics","authors":"Sophia N. Lyon, Joseph A. Tomoleoni, Julie L. Yee, Jessica A. Fujii, Nicole M. Thometz","doi":"10.3354/esr01348","DOIUrl":"https://doi.org/10.3354/esr01348","url":null,"abstract":"ABSTRACT: Sea otters <i>Enhydra lutris</i> are vital keystone predators throughout the North Pacific that were nearly extirpated during the maritime fur trade. Recovery of southern sea otters <i>E. l. nereis</i> has proceeded slowly, with much of their historical range remaining unoccupied, resulting in reduced ecosystem functioning. Numerous studies have used foraging metrics to assess the population status of southern sea otters throughout their current range, but little is known about the northern range extent, where a stall in expansion has limited recovery. Thus, we collected census and foraging data of sea otters at Año Nuevo State Park, California, from 2019 to 2021 to determine sea otter abundance, diet composition, diet diversity, and average energy intake rate at the northern range edge. We then assessed regional population status by comparing values from Año Nuevo with previously collected data from other locations in California, including high-density, range center sites and low-density, range periphery sites. We found that sea otter density at Año Nuevo was greater than surrounding areas at the northern range periphery, and the average (±95% CI) energy intake (9.51 ± 0.91 kcal min<sup>-1</sup>) more closely resembled values observed at high-density sites. Further, dietary diversity (using the Shannon-Wiener index, <i>H</i>) was intermediate between previously studied high- and low-density populations (<i>H</i> = 1.81), with crabs making up the largest proportion of the diet (~56%). Overall, this study highlights possible effects of occupation time and range stagnation, identifies unique aspects of the prey resource base at Año Nuevo, and provides insight into the ongoing lack of northern range expansion.","PeriodicalId":48746,"journal":{"name":"Endangered Species Research","volume":null,"pages":null},"PeriodicalIF":3.1,"publicationDate":"2024-08-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142194972","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 Galapagos Islands, renowned for their unique biodiversity, face a growing crisis, with over half of their endemic vascular plants under threat of extinction. Among the threatened flora, Lecocarpus lecocarpoides is classified as endangered, but is one of the least studied species. We present novel insights into the biology of L. lecocarpoides, acquired during the propagation of individuals for subsequent transplantation into their native habitat. The study encompasses seed viability, germination, growth, phenology, and morphology. Herbarium seeds were shown to remain viable for over 2 decades, highlighting the potential for seed bank conservation. In our germination experiment, which began with just 50 seeds, seed scarification resulted in a high germination rate of 75%. The resulting seedlings were planted in 2 sizes of pots and nurtured as seed producers. The plants in larger pots grew on average twice as tall and with nearly double the stem diameter of those in smaller pots. They yielded over 8000 seeds for conservation efforts, providing information on the development and fruit production capacity of L. lecocarpoides. We show differences in diaspore spine length between L. lecocarpoides populations, supporting the distinction of 2 L. lecocarpoides subspecies. Our findings provide essential data to inform conservation strategies for this endemic Galapagos species.
ABSTRACT: 加拉帕戈斯群岛以其独特的生物多样性而闻名于世，但该群岛面临着日益严重的危机，半数以上的特有维管植物濒临灭绝。在濒危植物中，Lecocarpus lecocarpoides 被列为濒危物种，但却是研究最少的物种之一。我们对 L. lecocarpoides 的生物学特性提出了新的见解，这些见解是在繁殖个体以便随后移植到其原生栖息地的过程中获得的。研究内容包括种子活力、发芽、生长、物候学和形态学。标本馆种子的存活时间超过了 20 年，凸显了种子库保护的潜力。在我们的发芽实验中，一开始只有 50 粒种子，经过种子去痕后，发芽率高达 75%。获得的幼苗被种植在两种大小的花盆中，并作为种子生产者进行培育。大花盆中的植株平均长高两倍，茎直径几乎是小花盆中植株的两倍。它们为保护工作提供了 8000 多粒种子，提供了有关 L. lecocarpoides 发育和果实生产能力的信息。我们的研究结果表明，L. lecocarpoides 种群之间的子囊孢子脊长度存在差异，这支持了两个 L. lecocarpoides 亚种的区分。我们的发现为这一加拉帕戈斯特有物种的保护策略提供了重要数据。
{"title":"Advancing conservation strategies for the endangered Galapagos plant Lecocarpus lecocarpoides: insights from ex situ propagation","authors":"Anna Calle-Loor, Patricia Jaramillo Díaz","doi":"10.3354/esr01352","DOIUrl":"https://doi.org/10.3354/esr01352","url":null,"abstract":"ABSTRACT: The Galapagos Islands, renowned for their unique biodiversity, face a growing crisis, with over half of their endemic vascular plants under threat of extinction. Among the threatened flora, <i>Lecocarpus lecocarpoides</i> is classified as endangered, but is one of the least studied species. We present novel insights into the biology of <i>L. lecocarpoides</i>, acquired during the propagation of individuals for subsequent transplantation into their native habitat. The study encompasses seed viability, germination, growth, phenology, and morphology. Herbarium seeds were shown to remain viable for over 2 decades, highlighting the potential for seed bank conservation. In our germination experiment, which began with just 50 seeds, seed scarification resulted in a high germination rate of 75%. The resulting seedlings were planted in 2 sizes of pots and nurtured as seed producers. The plants in larger pots grew on average twice as tall and with nearly double the stem diameter of those in smaller pots. They yielded over 8000 seeds for conservation efforts, providing information on the development and fruit production capacity of <i>L. lecocarpoides</i>. We show differences in diaspore spine length between <i>L. lecocarpoides</i> populations, supporting the distinction of 2 <i>L. lecocarpoides</i> subspecies. Our findings provide essential data to inform conservation strategies for this endemic Galapagos species.","PeriodicalId":48746,"journal":{"name":"Endangered Species Research","volume":null,"pages":null},"PeriodicalIF":3.1,"publicationDate":"2024-08-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142194984","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}
Todd R. Robeck, Rodrigo S. Amaral, Karen J. Steinman, Jason L. Blum, Anthony R. Martin, Gisele A. Montano, Don R. Bergfelt, Vera M. F. da Silva
ABSTRACT: Reproductive hormone profiles were described against physical characteristics during growth and development in male and female botos (Amazon River dolphins Inia geoffrensis) and during pregnancy. We determined hormone concentrations in 226 wild botos located in Mamirauá Reserve, Amazonas State, Brazil, as a part of the long-term population monitoring program known as Projeto Boto. Additionally, we applied receiver operator characteristic (ROC) analysis to compare diagnostic probabilities of using ultrasound, hormones, or combinations of these to detect pregnancy. Based on single-point analysis of serum testosterone (T), males with <2.5 ng ml-1 T and a mean 163 cm total body length were classified as immature, 2.5 to <4.9 ng ml-1 T and 183 cm as pubescent, and >5 ng ml-1 T and 227 cm as adult botos. For females, only progesterone (P4), T, relaxin (Rlx), and the combination of P4 × T2 were significantly different between non-pregnant and pregnant females, but androstenedione (A4) and the P4:T ratio were not. ROC analysis indicated that ultrasound and P4 × T2 were considered excellent as pregnancy diagnostic tests, and P4, T, and Rlx were classified as good predictors. Results indicated that negative and positive predictive probabilities from each diagnostic test could be used to accurately predict a pregnancy and calf loss rate of 13% for this population. Application of these methods for evaluating wild population reproductive success from a single serum sample can now be used for health evaluations of wild populations of boto and provide timely information for the development or evaluation of any conservation initiatives.
摘要：我们根据雌雄斑纹海豚（亚马逊河海豚Inia geoffrensis）生长发育期间和怀孕期间的身体特征描述了生殖激素谱系。我们测定了位于巴西亚马孙州马米劳亚保护区的 226 头野生斑纹海豚的激素浓度，这是名为 "Projeto Boto "的长期种群监测项目的一部分。此外，我们还应用受体运算特征（ROC）分析比较了使用超声波、激素或它们的组合检测怀孕的诊断概率。根据血清睾酮（T）的单点分析，体长为2.5 ng ml-1 T、平均体长为163厘米的雄性为未成年，体长为2.5至4.9 ng ml-1 T、平均体长为183厘米的为青春期，体长为5 ng ml-1 T、平均体长为227厘米的为成年雌性。就雌性而言，只有孕酮（P4）、T、松弛素（Rlx）以及 P4 × T2 的组合在未孕雌性和妊娠雌性之间存在显著差异，但雄烯二酮（A4）和 P4:T 的比值没有显著差异。ROC 分析表明，超声波和 P4 × T2 被认为是极佳的妊娠诊断测试，而 P4、T 和 Rlx 被归类为良好的预测指标。结果表明，每种诊断测试的阴性和阳性预测概率可用于准确预测该种群 13% 的妊娠率和犊牛损失率。应用这些方法从单份血清样本中评估野生种群的繁殖成功率，现在可用于野生波图种群的健康评估，并为制定或评估任何保护措施提供及时的信息。
{"title":"Combining reproductive endocrinology and ROC analysis to identify changes with sex, age, and pregnancy status in botos Inia geoffrensis","authors":"Todd R. Robeck, Rodrigo S. Amaral, Karen J. Steinman, Jason L. Blum, Anthony R. Martin, Gisele A. Montano, Don R. Bergfelt, Vera M. F. da Silva","doi":"10.3354/esr01351","DOIUrl":"https://doi.org/10.3354/esr01351","url":null,"abstract":"ABSTRACT: Reproductive hormone profiles were described against physical characteristics during growth and development in male and female botos (Amazon River dolphins <i>Inia geoffrensis</i>) and during pregnancy. We determined hormone concentrations in 226 wild botos located in Mamirauá Reserve, Amazonas State, Brazil, as a part of the long-term population monitoring program known as Projeto Boto. Additionally, we applied receiver operator characteristic (ROC) analysis to compare diagnostic probabilities of using ultrasound, hormones, or combinations of these to detect pregnancy. Based on single-point analysis of serum testosterone (T), males with <2.5 ng ml<sup>-1</sup> T and a mean 163 cm total body length were classified as immature, 2.5 to <4.9 ng ml<sup>-1</sup> T and 183 cm as pubescent, and >5 ng ml<sup>-1</sup> T and 227 cm as adult botos. For females, only progesterone (P4), T, relaxin (Rlx), and the combination of P4 × T<sup>2</sup> were significantly different between non-pregnant and pregnant females, but androstenedione (A4) and the P4:T ratio were not. ROC analysis indicated that ultrasound and P4 × T<sup>2</sup> were considered excellent as pregnancy diagnostic tests, and P4, T, and Rlx were classified as good predictors. Results indicated that negative and positive predictive probabilities from each diagnostic test could be used to accurately predict a pregnancy and calf loss rate of 13% for this population. Application of these methods for evaluating wild population reproductive success from a single serum sample can now be used for health evaluations of wild populations of boto and provide timely information for the development or evaluation of any conservation initiatives.","PeriodicalId":48746,"journal":{"name":"Endangered Species Research","volume":null,"pages":null},"PeriodicalIF":3.1,"publicationDate":"2024-08-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142194968","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}
Ana Rita Patrício, Sophia A. Coveney, Anna Barbanti, Castro Barbosa, Annette C. Broderick, Nahi ElBar, Brendan J. Godley, Joana M. Hancock, Aissa Regalla, Cheibani Senhoury, Ebaye Sidina, Benoît de Thoisy, Dominic Tilley, Sam Weber, Paulo Catry
ABSTRACT: Understanding population connectivity is paramount for effective conservation. While genetic tools have elucidated sea turtle migration patterns, notable data gaps limit our understanding of ocean-wide connectivity, especially regarding east Atlantic green turtles. We characterized the genetic composition of a globally important green turtle foraging aggregation at the Banc d’Arguin, Mauritania, incorporating data from 323 individuals captured between 2018 and 2021. Using extended mitochondrial DNA D-loop (738 base pairs [bp]) and mitochondrial short tandem repeat (mtSTR; ~200 bp) markers, we assessed the genetic structure of Atlantic green turtle foraging aggregations and estimated the most likely origin of immature green turtles from the Banc d’Arguin using mixed stock analyses (MSAs). We identified 6 D-loop haplotypes, with a clear dominance of CM-A8.1 (91.8%) followed by CM-A5.1 (6.3%) and 4 rare haplotypes: CM-A1.4, CMA6.1, CM24.1 and CM36.1. We found 13 mtSTR haplotypes, with ‘7-12-4-4’ being dominant (89.0%). The genetic composition at the Banc d’Arguin differed significantly from the only foraging aggregation studied in West Africa to date—in the archipelago of Cabo Verde (located ca. 750 km from the Banc d’Arguin)—dominated by haplotype CM-A5. The MSA combining both genetic markers indicated that 87.6% of immature green turtles at the Banc d’Arguin originate from the major East Atlantic rookery at Poilão (Guinea-Bissau), but 11.6% come from more distant rookeries in South America (8.1%) and potentially Ascension Island (3.4%). We suggest that green turtle transatlantic movements may be more common than previously thought and highlight the importance of the Banc d’Arguin as a regional foraging hub for this species.
{"title":"Atlantic connectivity of a major green sea turtle Chelonia mydas foraging aggregation at the Banc d’Arguin, Mauritania","authors":"Ana Rita Patrício, Sophia A. Coveney, Anna Barbanti, Castro Barbosa, Annette C. Broderick, Nahi ElBar, Brendan J. Godley, Joana M. Hancock, Aissa Regalla, Cheibani Senhoury, Ebaye Sidina, Benoît de Thoisy, Dominic Tilley, Sam Weber, Paulo Catry","doi":"10.3354/esr01345","DOIUrl":"https://doi.org/10.3354/esr01345","url":null,"abstract":"ABSTRACT: Understanding population connectivity is paramount for effective conservation. While genetic tools have elucidated sea turtle migration patterns, notable data gaps limit our understanding of ocean-wide connectivity, especially regarding east Atlantic green turtles. We characterized the genetic composition of a globally important green turtle foraging aggregation at the Banc d’Arguin, Mauritania, incorporating data from 323 individuals captured between 2018 and 2021. Using extended mitochondrial DNA D-loop (738 base pairs [bp]) and mitochondrial short tandem repeat (mtSTR; ~200 bp) markers, we assessed the genetic structure of Atlantic green turtle foraging aggregations and estimated the most likely origin of immature green turtles from the Banc d’Arguin using mixed stock analyses (MSAs). We identified 6 D-loop haplotypes, with a clear dominance of CM-A8.1 (91.8%) followed by CM-A5.1 (6.3%) and 4 rare haplotypes: CM-A1.4, CMA6.1, CM24.1 and CM36.1. We found 13 mtSTR haplotypes, with ‘7-12-4-4’ being dominant (89.0%). The genetic composition at the Banc d’Arguin differed significantly from the only foraging aggregation studied in West Africa to date—in the archipelago of Cabo Verde (located ca. 750 km from the Banc d’Arguin)—dominated by haplotype CM-A5. The MSA combining both genetic markers indicated that 87.6% of immature green turtles at the Banc d’Arguin originate from the major East Atlantic rookery at Poilão (Guinea-Bissau), but 11.6% come from more distant rookeries in South America (8.1%) and potentially Ascension Island (3.4%). We suggest that green turtle transatlantic movements may be more common than previously thought and highlight the importance of the Banc d’Arguin as a regional foraging hub for this species.","PeriodicalId":48746,"journal":{"name":"Endangered Species Research","volume":null,"pages":null},"PeriodicalIF":3.1,"publicationDate":"2024-08-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142194971","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}
Lauren Heddle, Katharina J. Peters, Mark Hamann, Guido J. Parra
ABSTRACT: Coastal areas provide essential habitats for marine turtle nesting and hatching, but they are under increasing threat due to climate change and other anthropogenic impacts. Very little is known about the nesting habitat characteristics of flatback Natator depressus, green Chelonia mydas and loggerhead Caretta caretta turtles in eastern Queensland, which limits our ability to evaluate which nesting beaches are at risk due to anthropogenic and environmental disturbances and prioritise conservation and monitoring actions. Here, we used generalised linear models to investigate the relationship between the presence/absence of flatback, green and loggerhead turtle nests and environmental and topographic characteristics of 237 potential nesting sites along the central and southern coasts of Queensland. The presence of nesting flatback turtles was strongly correlated with the mainland and non-coral cay islands with decreasing latitude, as there is an interaction between site type and latitude. In contrast, green turtles preferred to nest on coral cays rather than mainland and island beaches. Loggerhead turtles were more likely to nest on coral cays, the mainland, then islands, with presence increasing with latitude. Among these site types and higher latitudes, presence was stronger on sheltered than on semi-exposed beaches. Identifying environmental and topographical features influencing the presence of nesting flatback, green and loggerhead turtles is an important first step to improve the conservation of these species by prioritising sites for monitoring and managing threats to important beaches.
{"title":"Nesting habitat characteristics of flatback Natator depressus, green Chelonia mydas and loggerhead Caretta caretta turtles in eastern Queensland, Australia","authors":"Lauren Heddle, Katharina J. Peters, Mark Hamann, Guido J. Parra","doi":"10.3354/esr01347","DOIUrl":"https://doi.org/10.3354/esr01347","url":null,"abstract":"ABSTRACT: Coastal areas provide essential habitats for marine turtle nesting and hatching, but they are under increasing threat due to climate change and other anthropogenic impacts. Very little is known about the nesting habitat characteristics of flatback <i>Natator depressus</i>, green <i>Chelonia mydas</i> and loggerhead <i>Caretta caretta</i> turtles in eastern Queensland, which limits our ability to evaluate which nesting beaches are at risk due to anthropogenic and environmental disturbances and prioritise conservation and monitoring actions. Here, we used generalised linear models to investigate the relationship between the presence/absence of flatback, green and loggerhead turtle nests and environmental and topographic characteristics of 237 potential nesting sites along the central and southern coasts of Queensland. The presence of nesting flatback turtles was strongly correlated with the mainland and non-coral cay islands with decreasing latitude, as there is an interaction between site type and latitude. In contrast, green turtles preferred to nest on coral cays rather than mainland and island beaches. Loggerhead turtles were more likely to nest on coral cays, the mainland, then islands, with presence increasing with latitude. Among these site types and higher latitudes, presence was stronger on sheltered than on semi-exposed beaches. Identifying environmental and topographical features influencing the presence of nesting flatback, green and loggerhead turtles is an important first step to improve the conservation of these species by prioritising sites for monitoring and managing threats to important beaches.","PeriodicalId":48746,"journal":{"name":"Endangered Species Research","volume":null,"pages":null},"PeriodicalIF":3.1,"publicationDate":"2024-08-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141884237","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}
Elisabeth M. A. Strain, Ashlee Bastiaansen, Russell J. Thomson, Jemina Stuart-Smith, Ana Vila-Concejo, Maria Byrne
ABSTRACT: The live-bearing sea star Parvulastra vivipara, 1 of only 6 Asteroidea species globally that gives birth to live young, had an uncertain conservation status due to data deficiencies and historical differences in research methods. Restricted to southeast Tasmania, its distinctive reproductive strategy, coupled with limited distribution, low genetic diversity, and geographically isolated populations makes P. vivipara populations highly susceptible to localised and global extinction. Since the species was described in 1969, ten different historical survey methods have been used to survey P. vivipara populations. Notably, the survey area at these locations has increased through time as P. vivipara abundances declined. In 2022, surveys revealed the persistence of P. vivipara populations at 10 of 15 historically documented locations. Five locations experienced local extinction of P. vivipara populations, 3 in the last 2 decades, and 4 locations had <150 individuals remaining. P. vivipara density has experienced a decline of 90% from the first surveys in 1974-2001 to recent surveys in 2022. Based on the current trajectory, it is predicted that the density of P. vivipara will decline to 1 ind. m-2 by 2033 and 1 ind. site-1 by 2111, with some locations experiencing this decline even sooner. The rapid decline and restricted area of occupancy mean that P. vivipara qualifies for Critically Endangered status under IUCN Red List criteria A1 and B1. There is a pressing need for standardised and ongoing monitoring, management of key threats, and recovery strategies to bolster local and global P. vivipara populations against the threat of extinction.
摘要：活体海星（Parvulastra vivipara）是全球仅有的 6 个能产下活体幼体的星形目物种之一，由于数据不足和研究方法的历史差异，其保护状况尚不确定。vivipara 局限于塔斯马尼亚东南部，其独特的繁殖策略、有限的分布、较低的遗传多样性和地理上孤立的种群，使得 P. vivipara 种群极易在局部地区和全球范围内灭绝。自 1969 年描述该物种以来，已经使用了 10 种不同的历史调查方法来调查 P. vivipara 种群。值得注意的是，随着 P. vivipara 数量的减少，这些地点的调查面积也随之增加。2022 年，调查显示，在 15 个有历史记载的地点中，有 10 个地点的 P. vivipara 种群持续存在。有 5 个地点的 P. vivipara 种群在当地灭绝，其中 3 个地点是在过去 20 年中灭绝的，4 个地点的 P. vivipara 种群仅存 150 个个体。从 1974-2001 年的首次调查到最近 2022 年的调查，维维巴拉鱼的密度下降了 90%。根据目前的轨迹，预计到 2033 年，P. vivipara 的密度将下降到 1 ind.这种快速下降和有限的栖息地意味着，根据世界自然保护联盟（IUCN）红色名录标准 A1 和 B1，P. vivipara 属于极度濒危物种。目前迫切需要进行标准化的持续监测、对主要威胁进行管理并制定恢复战略，以支持当地和全球的维氏豹种群抵御灭绝的威胁。
{"title":"A review of the conservation status and survey methods for the live-bearing sea star Parvulastra vivipara","authors":"Elisabeth M. A. Strain, Ashlee Bastiaansen, Russell J. Thomson, Jemina Stuart-Smith, Ana Vila-Concejo, Maria Byrne","doi":"10.3354/esr01346","DOIUrl":"https://doi.org/10.3354/esr01346","url":null,"abstract":"ABSTRACT: The live-bearing sea star <i>Parvulastra vivipara</i>, 1 of only 6 Asteroidea species globally that gives birth to live young, had an uncertain conservation status due to data deficiencies and historical differences in research methods. Restricted to southeast Tasmania, its distinctive reproductive strategy, coupled with limited distribution, low genetic diversity, and geographically isolated populations makes <i>P. vivipara</i> populations highly susceptible to localised and global extinction. Since the species was described in 1969, ten different historical survey methods have been used to survey <i>P. vivipara</i> populations. Notably, the survey area at these locations has increased through time as <i>P. vivipara</i> abundances declined. In 2022, surveys revealed the persistence of <i>P. vivipara</i> populations at 10 of 15 historically documented locations. Five locations experienced local extinction of <i>P. vivipara</i> populations, 3 in the last 2 decades, and 4 locations had <150 individuals remaining. <i>P. vivipara</i> density has experienced a decline of 90% from the first surveys in 1974-2001 to recent surveys in 2022. Based on the current trajectory, it is predicted that the density of <i>P. vivipara</i> will decline to 1 ind. m<sup>-2</sup> by 2033 and 1 ind. site<sup>-1</sup> by 2111, with some locations experiencing this decline even sooner. The rapid decline and restricted area of occupancy mean that <i>P. vivipara</i> qualifies for Critically Endangered status under IUCN Red List criteria A1 and B1. There is a pressing need for standardised and ongoing monitoring, management of key threats, and recovery strategies to bolster local and global <i>P. vivipara</i> populations against the threat of extinction.","PeriodicalId":48746,"journal":{"name":"Endangered Species Research","volume":null,"pages":null},"PeriodicalIF":3.1,"publicationDate":"2024-08-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141884238","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}
Fernando Medrano, Julio Hernández-Montoya, Sarah Saldanha, Yuliana Bedolla-Guzmán, Jacob González-Solís
ABSTRACT: Migration is an essential life stage in many species, but is little understood in some groups, e.g. storm-petrels. Considering that storm-petrels reside in non-breeding areas for over half of their lifespan, identifying these areas is a priority for conservation efforts. Townsend’s Hydrobates socorroensis and Ainley’s storm-petrels H. cheimomnestes are 2 threatened sister species, breeding allochronically on Guadalupe Island (Mexican Pacific), for which migratory patterns are unknown. In this article, we describe the non-breeding areas of these 2 species, assess artificial light events recorded by geolocators, and describe the birds’ daily activity patterns. We deployed geolocators from 2021 to 2023 and modeled migratory routes using SGAT. We successfully tracked 7 Townsend’s and 4 Ainley’s storm-petrels over their non-breeding period. Townsend’s storm-petrels were found to travel to the south of the Baja California Peninsula and spent most of the time in Mexican waters, while Ainley’s storm-petrels migrated toward Hawaii and spent most of the time on the high seas. For the Townsend’s storm-petrels, 16.1% of their core areas are in protected waters, whereas for Ainley’s storm-petrel, only 0.7% of the core areas are protected, and 0.8% of those areas are recognized as key biodiversity areas (KBAs). Further, our findings indicate that both species are mainly nocturnal, making them highly susceptible to the impacts of light pollution; we detected 6 artificial light events. Our findings also support the hypothesis that divergence in the migration patterns between allochronic populations could be a crucial factor in sympatric speciation, which seems likely in seasonal environments like the northern Pacific.
{"title":"Contrasting migratory ecology of two threatened and allochronic storm-petrels breeding in the Mexican Pacific","authors":"Fernando Medrano, Julio Hernández-Montoya, Sarah Saldanha, Yuliana Bedolla-Guzmán, Jacob González-Solís","doi":"10.3354/esr01344","DOIUrl":"https://doi.org/10.3354/esr01344","url":null,"abstract":"ABSTRACT: Migration is an essential life stage in many species, but is little understood in some groups, e.g. storm-petrels. Considering that storm-petrels reside in non-breeding areas for over half of their lifespan, identifying these areas is a priority for conservation efforts. Townsend’s <i>Hydrobates socorroensis</i> and Ainley’s storm-petrels <i>H. cheimomnestes</i> are 2 threatened sister species, breeding allochronically on Guadalupe Island (Mexican Pacific), for which migratory patterns are unknown. In this article, we describe the non-breeding areas of these 2 species, assess artificial light events recorded by geolocators, and describe the birds’ daily activity patterns. We deployed geolocators from 2021 to 2023 and modeled migratory routes using SGAT. We successfully tracked 7 Townsend’s and 4 Ainley’s storm-petrels over their non-breeding period. Townsend’s storm-petrels were found to travel to the south of the Baja California Peninsula and spent most of the time in Mexican waters, while Ainley’s storm-petrels migrated toward Hawaii and spent most of the time on the high seas. For the Townsend’s storm-petrels, 16.1% of their core areas are in protected waters, whereas for Ainley’s storm-petrel, only 0.7% of the core areas are protected, and 0.8% of those areas are recognized as key biodiversity areas (KBAs). Further, our findings indicate that both species are mainly nocturnal, making them highly susceptible to the impacts of light pollution; we detected 6 artificial light events. Our findings also support the hypothesis that divergence in the migration patterns between allochronic populations could be a crucial factor in sympatric speciation, which seems likely in seasonal environments like the northern Pacific.","PeriodicalId":48746,"journal":{"name":"Endangered Species Research","volume":null,"pages":null},"PeriodicalIF":3.1,"publicationDate":"2024-07-11","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141585089","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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