The investigation of tooth wear and pathology in freshwater dolphins can increase our understanding of their life history, including interactions with the environment and impacts of disease and morbidity. This paper evaluated the occurrence, prevalence and discussed the putative etiology of dental wear and pathology in freshwater dolphins - tucuxi (Sotalia fluviatilis) and the Amazon River dolphin (Inia geoffrensis) - from the central Amazon basin. Teeth of 29 Amazon River dolphins and 14 tucuxis were visually inspected to identify wear facets and the presence of pathology. Dental wear was observed in 55% (n = 16) of the Amazon River dolphin and 79% (n = 11) of the tucuxi specimens. For both species, superficial wear restricted to the tooth crown was more frequent. Calculus deposits were observed in both species, occurring in 14% of tucuxi (n = 2) and 41% of Amazon River dolphin (n = 12) specimens. Caries-like lesions were observed in a third of Amazon River dolphin specimens (n = 10), affecting 10% of the teeth (n = 197). Gross caries was the most commonly caries type observed. Only one tucuxi had caries-like lesions, affecting 1.6% of the teeth (n = 13). While conditions such as tooth wear arise from normal physiological processes, severe wear and pathology such as caries and calculus can contribute to further disease development and morbidity, impacting the health of the animals. Further studies using materials from museum collections in other regions from the Amazon Basin will help elucidate the occurrence, etiology, and health impact of tooth wear and dental pathology in freshwater cetaceans, contributing to our growing understanding of their life history.
{"title":"Tooth wear and dental pathology in Amazon River dolphins (Inia geoffrensis) and tucuxis (Sotalia fluviatilis)","authors":"C. Loch, Miriam Marmontel","doi":"10.5597/lajam00318","DOIUrl":"https://doi.org/10.5597/lajam00318","url":null,"abstract":"The investigation of tooth wear and pathology in freshwater dolphins can increase our understanding of their life history, including interactions with the environment and impacts of disease and morbidity. This paper evaluated the occurrence, prevalence and discussed the putative etiology of dental wear and pathology in freshwater dolphins - tucuxi (Sotalia fluviatilis) and the Amazon River dolphin (Inia geoffrensis) - from the central Amazon basin. Teeth of 29 Amazon River dolphins and 14 tucuxis were visually inspected to identify wear facets and the presence of pathology. Dental wear was observed in 55% (n = 16) of the Amazon River dolphin and 79% (n = 11) of the tucuxi specimens. For both species, superficial wear restricted to the tooth crown was more frequent. Calculus deposits were observed in both species, occurring in 14% of tucuxi (n = 2) and 41% of Amazon River dolphin (n = 12) specimens. Caries-like lesions were observed in a third of Amazon River dolphin specimens (n = 10), affecting 10% of the teeth (n = 197). Gross caries was the most commonly caries type observed. Only one tucuxi had caries-like lesions, affecting 1.6% of the teeth (n = 13). While conditions such as tooth wear arise from normal physiological processes, severe wear and pathology such as caries and calculus can contribute to further disease development and morbidity, impacting the health of the animals. Further studies using materials from museum collections in other regions from the Amazon Basin will help elucidate the occurrence, etiology, and health impact of tooth wear and dental pathology in freshwater cetaceans, contributing to our growing understanding of their life history.","PeriodicalId":17967,"journal":{"name":"Latin American Journal of Aquatic Mammals","volume":"12 2","pages":""},"PeriodicalIF":0.0,"publicationDate":"2024-02-22","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140439501","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Emma Deeks, P. Kratina, I. Normande, Aline da Silva Cerqueira, T. Dawson
How climate change alters persistence and distribution of endangered species is an urgent question in current ecological research. However, many species distribution models do not consider consumers in the context of their resources. The distribution and survival of the West Indian manatee (Trichechus manatus), listed as a Vulnerable species on the IUCN Red List, critically depend on seagrass resources and freshwater sources for drinking. We parameterized Maxent models with Bio-ORACLE environmental layers, freshwater proximity data, and modelled seagrass distance layers, to determine manatee and seagrass distributions under future climate change scenarios. We used two plausible IPCC Representative Concentration Pathways (RCP45 and RCP26, respectively) for the year 2050. The model fits had high accuracies and predicted a marked decline in seagrass coverage (RCP26: -1.9%, RCP45: -6%), coinciding with declines in manatee ranges (RCP26: -9%, RCP45: -11.8%). We also found that over 94% of the projected manatee distribution for all scenarios fell within the seagrass distribution. The analysis showed a decline in seagrass coverage to significantly impact manatee distributions, since the distance to seagrass ecological layer contributed significantly to manatee distributions, along with distance to freshwater sources. Our findings suggest that manatees will lose substantial range due to future climate change, but the extent and direction of this change will be mediated by the degree of warming and its impact on the resources manatees depend on.
{"title":"Proximity to freshwater and seagrass availability mediate the impacts of climate change on the distribution of the West Indian manatee","authors":"Emma Deeks, P. Kratina, I. Normande, Aline da Silva Cerqueira, T. Dawson","doi":"10.5597/lajam00321","DOIUrl":"https://doi.org/10.5597/lajam00321","url":null,"abstract":"How climate change alters persistence and distribution of endangered species is an urgent question in current ecological research. However, many species distribution models do not consider consumers in the context of their resources. The distribution and survival of the West Indian manatee (Trichechus manatus), listed as a Vulnerable species on the IUCN Red List, critically depend on seagrass resources and freshwater sources for drinking. We parameterized Maxent models with Bio-ORACLE environmental layers, freshwater proximity data, and modelled seagrass distance layers, to determine manatee and seagrass distributions under future climate change scenarios. We used two plausible IPCC Representative Concentration Pathways (RCP45 and RCP26, respectively) for the year 2050. The model fits had high accuracies and predicted a marked decline in seagrass coverage (RCP26: -1.9%, RCP45: -6%), coinciding with declines in manatee ranges (RCP26: -9%, RCP45: -11.8%). We also found that over 94% of the projected manatee distribution for all scenarios fell within the seagrass distribution. The analysis showed a decline in seagrass coverage to significantly impact manatee distributions, since the distance to seagrass ecological layer contributed significantly to manatee distributions, along with distance to freshwater sources. Our findings suggest that manatees will lose substantial range due to future climate change, but the extent and direction of this change will be mediated by the degree of warming and its impact on the resources manatees depend on.","PeriodicalId":17967,"journal":{"name":"Latin American Journal of Aquatic Mammals","volume":"29 13","pages":""},"PeriodicalIF":0.0,"publicationDate":"2024-02-22","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140442168","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Lucas Milmann, Larissa Rosa de Oliveira, Daniel Danilewicz, Rodrigo Machado, Janaína Carrion Wickert, Federico Sucunza, Márcio Borges-Martins, Júlio E. Baumgarten, Paulo Henrique Ott
The ecology and distribution of most baleen whales are poorly known in Brazilian waters, despite the history of whaling and the recent increase in the research effort. Although stranding data presents some caveats, it is useful to understand patterns of distribution and occurrence and to detect population trends. In this scenario, data from 25 years of a monitoring marine mammal stranding program were used to evaluate the composition and spatial-temporal patterns of Balaenoptera whales in southern Brazil. A stretch of 270 km on the coast of Rio Grande do Sul State (from 29°20’S to 31°21’S) was surveyed year-round between 1993 and 2018. Whales were identified, measured and sex determined whenever possible. Molecular identification through mtDNA analysis was obtained for 22 individuals and confirmed field identification in 17 cases. Forty-eight whales of four species were recorded: common minke whale B. acutorostrata n = 27, Antarctic minke whale B. bonaerensis n = 1, Bryde’s whale B. brydei n = 13, fin whale B. physalus n = 1. In addition, six whales were not identified at species level due to advanced decomposition. The larger number of strandings of common minke and Bryde’s whales may be related to their greater abundance and/or more coastal distribution. Both species were recorded year-round, but strandings of common minke and Bryde’s whales occurred mostly during winter/spring (77.77%) and spring/summer (66.66%), respectively. Although Bryde’s whales appear to remain in southern Brazilian waters during the entire year, the results suggest the existence of seasonal inshore-offshore movements. Moreover, the greater number of strandings of juveniles of common minke whales compared to adults (ratio 1.86:1) and their occurrence in different seasons suggest that some immature individuals may not leave this region, as previously pointed out by other studies. This long-term survey brings new evidence of the importance of this region in the Southwestern Atlantic Ocean for some Balaenoptera species.
尽管有捕鲸的历史和最近的研究努力，但大多数须鲸的生态和分布在巴西水域鲜为人知。虽然搁浅数据有一些缺点，但对于了解分布和发生的模式以及探测种群趋势是有用的。在本情景中，研究人员使用了25年监测海洋哺乳动物搁浅项目的数据来评估巴西南部Balaenoptera鲸的组成和时空格局。在1993年至2018年期间，对南里奥格兰德州海岸270公里(29°20′s至31°21′s)的一段区域进行了全年调查。只要有可能，就对鲸鱼进行鉴定、测量和性别确定。通过mtDNA分析获得分子鉴定22例，现场鉴定17例。记录到普通小须鲸B. acutorostrata n = 27，南极小须鲸B. bonaerensis n = 1，布氏鲸B. brydei n = 13，长须鲸B. physalus n = 1。此外，有6只鲸鱼由于深度分解而未被确定为物种水平。普通小须鲸和白鲸搁浅的数量较多可能与它们数量较多和/或分布在沿海地区有关。这两个物种全年均有记录，但普通小须鲸和白头鲸搁浅主要发生在冬春季(77.77%)和春夏季(66.66%)。尽管布氏鲸似乎全年都呆在巴西南部水域，但研究结果表明，它们存在季节性的近海运动。此外，普通小须鲸幼鲸搁浅的数量比成年小须鲸多(比例为1.86:1)，而且发生在不同的季节，这表明一些未成熟的个体可能不会离开这一地区，正如之前其他研究指出的那样。这项长期调查为西南大西洋这一地区对一些Balaenoptera物种的重要性提供了新的证据。
{"title":"Overview of Balaenoptera whales strandings in Southern Brazil from 1993 to 2018","authors":"Lucas Milmann, Larissa Rosa de Oliveira, Daniel Danilewicz, Rodrigo Machado, Janaína Carrion Wickert, Federico Sucunza, Márcio Borges-Martins, Júlio E. Baumgarten, Paulo Henrique Ott","doi":"10.5597/lajam00315","DOIUrl":"https://doi.org/10.5597/lajam00315","url":null,"abstract":"The ecology and distribution of most baleen whales are poorly known in Brazilian waters, despite the history of whaling and the recent increase in the research effort. Although stranding data presents some caveats, it is useful to understand patterns of distribution and occurrence and to detect population trends. In this scenario, data from 25 years of a monitoring marine mammal stranding program were used to evaluate the composition and spatial-temporal patterns of Balaenoptera whales in southern Brazil. A stretch of 270 km on the coast of Rio Grande do Sul State (from 29°20’S to 31°21’S) was surveyed year-round between 1993 and 2018. Whales were identified, measured and sex determined whenever possible. Molecular identification through mtDNA analysis was obtained for 22 individuals and confirmed field identification in 17 cases. Forty-eight whales of four species were recorded: common minke whale B. acutorostrata n = 27, Antarctic minke whale B. bonaerensis n = 1, Bryde’s whale B. brydei n = 13, fin whale B. physalus n = 1. In addition, six whales were not identified at species level due to advanced decomposition. The larger number of strandings of common minke and Bryde’s whales may be related to their greater abundance and/or more coastal distribution. Both species were recorded year-round, but strandings of common minke and Bryde’s whales occurred mostly during winter/spring (77.77%) and spring/summer (66.66%), respectively. Although Bryde’s whales appear to remain in southern Brazilian waters during the entire year, the results suggest the existence of seasonal inshore-offshore movements. Moreover, the greater number of strandings of juveniles of common minke whales compared to adults (ratio 1.86:1) and their occurrence in different seasons suggest that some immature individuals may not leave this region, as previously pointed out by other studies. This long-term survey brings new evidence of the importance of this region in the Southwestern Atlantic Ocean for some Balaenoptera species.","PeriodicalId":17967,"journal":{"name":"Latin American Journal of Aquatic Mammals","volume":"13 ","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2023-10-26","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"135012255","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Lucas Lima De Oliveira, Ticiana Fettermann, Renata Karina Marconi Marcançoli, Daniel Danilewicz
{"title":"Drone survey provides preliminary insights into the biological aspects of Bryde’s whales in southeastern Brazil","authors":"Lucas Lima De Oliveira, Ticiana Fettermann, Renata Karina Marconi Marcançoli, Daniel Danilewicz","doi":"10.5597/lajam00314","DOIUrl":"https://doi.org/10.5597/lajam00314","url":null,"abstract":"","PeriodicalId":17967,"journal":{"name":"Latin American Journal of Aquatic Mammals","volume":"6 5","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2023-10-26","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"135012258","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"An unexpected event related to the aquatic mammals of Latin America","authors":"Daniel Gonzalez-Socoloske","doi":"10.5597/lajam00304","DOIUrl":"https://doi.org/10.5597/lajam00304","url":null,"abstract":"","PeriodicalId":17967,"journal":{"name":"Latin American Journal of Aquatic Mammals","volume":"141 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2023-10-26","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"135013569","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Given the scarcity of cetacean records in Central American waters and even more in the Caribbean waters (Bolaños-Jiménez et al., 2014, 2021, 2023; Alvarado-Hofmeister, 2021; Valencia Cubillos, 2022), it is essential to document the presence of particular species in specific areas to refine the regional cetacean inventory. Here, we report on the presence of a dead, young Clymene dolphin in waters off Tortuguero Volcano, Caribbean Sea, the first record of the species for Costa Rica, more than 800 km afar from the nearest available record in the Gulf of Morrosquillo, Colombia (Mignucci et al., 2021). On 02 November 2022, a dead dolphin was found floating in Costa Rican waters approximately 45 km from Tortuguero Hill (approx. 10°48’N, 83°00’W, Fig. 1) by the crew of a sport fishing boat. According to the General Bathymetric Chart of the Oceans The genus Stenella includes five species, of which the Atlantic spotted (Stenella frontalis) and the Clymene (S. clymene) dolphins are endemic to the Atlantic Ocean (Perrin et al., 1981; Fertl et al., 2003; Moreno et al., 2005, Jefferson et al., 2015). The Clymene dolphin is described as the smallest of the genus Stenella and reaches at least 1.97 m (males) and 1.90 m (females); moreover, the neonatal length is unknown but is thought to be less than 1.2 m (Jefferson et al., 2015). This oceanic species is found only in the tropical and subtropical Atlantic Ocean, including the Caribbean Sea and the Gulf of Mexico, and prefers deep waters between 250-5,000 m (Perrin et al., 1981; do Amaral et al., 2015; Jefferson et al., 2015; Barragán-Barrera et al., 2019). Recent reports confirm the species’ presence in the Mexican Caribbean, Belize, Colombia, and Venezuela (Niño Torres et al., 2015; Ramos et al., 2016; Briceño et al., 2020; Mignucci et al., 2021) but records are unknown for other Caribbean Central American waters (i.e., Nicaragua, Costa Rica, and Panama).
{"title":"First record of the Clymene dolphin (Stenella clymene Gray, 1850) in Costa Rican waters","authors":"Jaime Bolaños-Jiménez, Gilberto Borges-Guzmán, Gabriela Hernández-Mora","doi":"10.5597/lajam00313","DOIUrl":"https://doi.org/10.5597/lajam00313","url":null,"abstract":"Given the scarcity of cetacean records in Central American waters and even more in the Caribbean waters (Bolaños-Jiménez et al., 2014, 2021, 2023; Alvarado-Hofmeister, 2021; Valencia Cubillos, 2022), it is essential to document the presence of particular species in specific areas to refine the regional cetacean inventory. Here, we report on the presence of a dead, young Clymene dolphin in waters off Tortuguero Volcano, Caribbean Sea, the first record of the species for Costa Rica, more than 800 km afar from the nearest available record in the Gulf of Morrosquillo, Colombia (Mignucci et al., 2021). On 02 November 2022, a dead dolphin was found floating in Costa Rican waters approximately 45 km from Tortuguero Hill (approx. 10°48’N, 83°00’W, Fig. 1) by the crew of a sport fishing boat. According to the General Bathymetric Chart of the Oceans The genus Stenella includes five species, of which the Atlantic spotted (Stenella frontalis) and the Clymene (S. clymene) dolphins are endemic to the Atlantic Ocean (Perrin et al., 1981; Fertl et al., 2003; Moreno et al., 2005, Jefferson et al., 2015). The Clymene dolphin is described as the smallest of the genus Stenella and reaches at least 1.97 m (males) and 1.90 m (females); moreover, the neonatal length is unknown but is thought to be less than 1.2 m (Jefferson et al., 2015). This oceanic species is found only in the tropical and subtropical Atlantic Ocean, including the Caribbean Sea and the Gulf of Mexico, and prefers deep waters between 250-5,000 m (Perrin et al., 1981; do Amaral et al., 2015; Jefferson et al., 2015; Barragán-Barrera et al., 2019). Recent reports confirm the species’ presence in the Mexican Caribbean, Belize, Colombia, and Venezuela (Niño Torres et al., 2015; Ramos et al., 2016; Briceño et al., 2020; Mignucci et al., 2021) but records are unknown for other Caribbean Central American waters (i.e., Nicaragua, Costa Rica, and Panama).","PeriodicalId":17967,"journal":{"name":"Latin American Journal of Aquatic Mammals","volume":"13 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2023-09-27","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"135534404","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
2017). In the southeastern Pacific, intra-annual shifts in food resource availability related to coastal upwelling cycles, and the occurrence of La Niña phenomena have been discussed as possible explanations for the repeated appearance of individuals farther north in Chile (Sepúlveda et al., 2007; Pacheco et al., 2011), Ecuador (Páez-Rosas et al., 2018), Colombia (Ávila et al., 2021), and Panama (Redwood & Félix, 2018). Like in southern Chile (Acevedo et al., 2019; Cárcamo et al., 2019), increasing numbers of anecdotal southern elephant seal sightings in the Eastern Tropical Pacific have been recently hypothesized to result from two causes that would hence outweigh ENSO (El Niño-Southern Oscillation) cycling as sole possible contributor: 1) a possible density-dependent extralimital growth of the three Atlantic populations, and 2) global climate change-related largescale regime shifts in the Southern Ocean (Alava et al., 2022). An observed prevalence of often immature or subadult males in all of these northerly anecdotal sighting reports – at their time often considered to be linked to vagrancy (Páez-Rosas et al., 2018) – has been attributed to sex-based differences in southern elephant seal foraging behavior/dietary niches and to age-dependent experience in the selection of haul-out sites (Mulaudzi et al., 2008; Acevedo et al., 2016; Sepúlveda et al., 2018). On a global scale, extra-distributional coastal sightings include male adults in the southeastern Atlantic (Bester et al., 2022) and, among others, infants in the southwestern Atlantic (Siciliano et al., 2020), encouraging comparative studies concerning (re-)colonization and range extension processes. As research on the ecology and behavior of southern elephant seals in their re-colonized historic southeastern Pacific range is only beginning, detailed observations of single sightings might help to further develop working hypotheses. Therefore, details of the first modern record of a southern elephant seal in Los Ríos Region, near 40° S in southern Chile (Fig. 1A), are described here. Cárcamo et al. (2019) had already collected census data to reassess the distribution of southern elephant seals in the southeastern Pacific. They included southern elephant seal sighting records from authorities (Servicio Nacional de Pesca y Acuicultura/Chile National Fishery and Aquaculture Service of Chile – SERNAPESCA); records from 2009 to 2016) and The distribution of southern elephant seals (Mirounga leonina Linnaeus, 1758) in the southeastern Pacific has been subject to revision in recent years (Acevedo et al., 2016, 2019; Cárcamo et al., 2019). Southern elephant seals were hunted close to extinction by humans (Hindell & Perrin, 2009; Acevedo et al., 2016, 2019). However, since the late 20th century they have been re-colonizing breeding sites in southernmost Chile’s Magallanes Region (e.g. Cáceres, 2013; Acevedo et al., 2016; Capella et al., 2017). The recent documentation of pups and a birth event at diff
{"title":"Note on the first modern record of a southern elephant seal (Mirounga leonina Linnaeus, 1758) in Los Ríos Region, southern Chile","authors":"Henrike Niebaum","doi":"10.5597/lajam00312","DOIUrl":"https://doi.org/10.5597/lajam00312","url":null,"abstract":"2017). In the southeastern Pacific, intra-annual shifts in food resource availability related to coastal upwelling cycles, and the occurrence of La Niña phenomena have been discussed as possible explanations for the repeated appearance of individuals farther north in Chile (Sepúlveda et al., 2007; Pacheco et al., 2011), Ecuador (Páez-Rosas et al., 2018), Colombia (Ávila et al., 2021), and Panama (Redwood & Félix, 2018). Like in southern Chile (Acevedo et al., 2019; Cárcamo et al., 2019), increasing numbers of anecdotal southern elephant seal sightings in the Eastern Tropical Pacific have been recently hypothesized to result from two causes that would hence outweigh ENSO (El Niño-Southern Oscillation) cycling as sole possible contributor: 1) a possible density-dependent extralimital growth of the three Atlantic populations, and 2) global climate change-related largescale regime shifts in the Southern Ocean (Alava et al., 2022). An observed prevalence of often immature or subadult males in all of these northerly anecdotal sighting reports – at their time often considered to be linked to vagrancy (Páez-Rosas et al., 2018) – has been attributed to sex-based differences in southern elephant seal foraging behavior/dietary niches and to age-dependent experience in the selection of haul-out sites (Mulaudzi et al., 2008; Acevedo et al., 2016; Sepúlveda et al., 2018). On a global scale, extra-distributional coastal sightings include male adults in the southeastern Atlantic (Bester et al., 2022) and, among others, infants in the southwestern Atlantic (Siciliano et al., 2020), encouraging comparative studies concerning (re-)colonization and range extension processes. As research on the ecology and behavior of southern elephant seals in their re-colonized historic southeastern Pacific range is only beginning, detailed observations of single sightings might help to further develop working hypotheses. Therefore, details of the first modern record of a southern elephant seal in Los Ríos Region, near 40° S in southern Chile (Fig. 1A), are described here. Cárcamo et al. (2019) had already collected census data to reassess the distribution of southern elephant seals in the southeastern Pacific. They included southern elephant seal sighting records from authorities (Servicio Nacional de Pesca y Acuicultura/Chile National Fishery and Aquaculture Service of Chile – SERNAPESCA); records from 2009 to 2016) and The distribution of southern elephant seals (Mirounga leonina Linnaeus, 1758) in the southeastern Pacific has been subject to revision in recent years (Acevedo et al., 2016, 2019; Cárcamo et al., 2019). Southern elephant seals were hunted close to extinction by humans (Hindell & Perrin, 2009; Acevedo et al., 2016, 2019). However, since the late 20th century they have been re-colonizing breeding sites in southernmost Chile’s Magallanes Region (e.g. Cáceres, 2013; Acevedo et al., 2016; Capella et al., 2017). The recent documentation of pups and a birth event at diff","PeriodicalId":17967,"journal":{"name":"Latin American Journal of Aquatic Mammals","volume":"290 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2023-09-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"135393579","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
The presence of the offshore bottlenose dolphin (Tursiops truncatus) is poorly understood for most of the southeast Pacific Ocean. Its wide distribution, low density, and lack of understanding of its ecology make the species unpredictable to observe and difficult to study compared to the coastal ecotype. We assessed the occurrence of offshore bottlenose dolphins off the central coast of Ecuador (01°36’ S, 80°58’ W) using information taken from 2001 to 2022. Data were collected by two research groups based 80 km apart, one in Puerto López (north) and the other in Salinas (south). A total of 48 dolphin groups were documented, 22 at Puerto López and 26 at Salinas. In Puerto López, 163 dolphins were individually identified, of which 70 intra-annual sightings and 102 inter-annual sightings were found. Inter-annual resightings at Puerto López corresponded to 55 individuals (33.7%) recorded between two and 17 years (mean = 5.82 years, SD = 5.1). In Salinas, 58 dolphins were identified, without intra-annual resightings and only two inter-annual sightings. Only one individual was recorded in both areas. Two site fidelity indexes were calculated, Occurrence (Oi) and Permanence (Pi), resulting in 11 and 13.7 times higher respectively, in Puerto López. The abundance at Puerto López, 163 animals (95% CI, 120 - 203) in 2021-2022, was estimated with a closed population model. The prevalence of scars associated with previous encounters with fishing gear was 43.6%, commensal barnacle (Xenobalanus globicipitis) infestation 42.3%, predation 3.6%, and dermal nodules 0.61%. Our findings suggest both site fidelity and some degree of population structure, but additional monitoring and genetic studies are needed to clarify these aspects. Nevertheless, this study provides information on key aspects necessary for developing conservation strategies for offshore bottlenose dolphins.
{"title":"Occurrence, abundance and some ecological aspects of the offshore bottlenose dolphin off Ecuador’s central coast","authors":"Fernando Félix, Cristina Castro","doi":"10.5597/lajam00310","DOIUrl":"https://doi.org/10.5597/lajam00310","url":null,"abstract":"The presence of the offshore bottlenose dolphin (Tursiops truncatus) is poorly understood for most of the southeast Pacific Ocean. Its wide distribution, low density, and lack of understanding of its ecology make the species unpredictable to observe and difficult to study compared to the coastal ecotype. We assessed the occurrence of offshore bottlenose dolphins off the central coast of Ecuador (01°36’ S, 80°58’ W) using information taken from 2001 to 2022. Data were collected by two research groups based 80 km apart, one in Puerto López (north) and the other in Salinas (south). A total of 48 dolphin groups were documented, 22 at Puerto López and 26 at Salinas. In Puerto López, 163 dolphins were individually identified, of which 70 intra-annual sightings and 102 inter-annual sightings were found. Inter-annual resightings at Puerto López corresponded to 55 individuals (33.7%) recorded between two and 17 years (mean = 5.82 years, SD = 5.1). In Salinas, 58 dolphins were identified, without intra-annual resightings and only two inter-annual sightings. Only one individual was recorded in both areas. Two site fidelity indexes were calculated, Occurrence (Oi) and Permanence (Pi), resulting in 11 and 13.7 times higher respectively, in Puerto López. The abundance at Puerto López, 163 animals (95% CI, 120 - 203) in 2021-2022, was estimated with a closed population model. The prevalence of scars associated with previous encounters with fishing gear was 43.6%, commensal barnacle (Xenobalanus globicipitis) infestation 42.3%, predation 3.6%, and dermal nodules 0.61%. Our findings suggest both site fidelity and some degree of population structure, but additional monitoring and genetic studies are needed to clarify these aspects. Nevertheless, this study provides information on key aspects necessary for developing conservation strategies for offshore bottlenose dolphins.","PeriodicalId":17967,"journal":{"name":"Latin American Journal of Aquatic Mammals","volume":"31 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2023-09-12","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"135879177","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
V. Ribeiro, E. Hajdu, Victor Do Santos Luiz, Gemany Caetano Rosa dos Santos, Juarez De Castro Cabral, Nathalia De Sousa Motta, Juliana Plácido Guimarães, Carolina Pacheco Bertozzi
and were more solitary. In adult Indo-Pacific humpback dolphins ( Sousa chinensis ), carrying a sponge on their rostrum as a tool was also observed (Parra
{"title":"Ingestion of yellow tube sponge (Aplysina fistularis Pallas, 1766) (Porifera, Demospongiae) by short-finned pilot whale (Globicephala macrorhynchus Gray, 1846)","authors":"V. Ribeiro, E. Hajdu, Victor Do Santos Luiz, Gemany Caetano Rosa dos Santos, Juarez De Castro Cabral, Nathalia De Sousa Motta, Juliana Plácido Guimarães, Carolina Pacheco Bertozzi","doi":"10.5597/lajam00309","DOIUrl":"https://doi.org/10.5597/lajam00309","url":null,"abstract":"and were more solitary. In adult Indo-Pacific humpback dolphins ( Sousa chinensis ), carrying a sponge on their rostrum as a tool was also observed (Parra","PeriodicalId":17967,"journal":{"name":"Latin American Journal of Aquatic Mammals","volume":"1 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2023-08-18","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"82314018","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Arturo Romero-Tenorio, Fernando R Elorriaga Verplancken, J. Gallo‐Reynoso, Luis Arturo Álvarez-Márquez, Isai D. Barba‐Acuña
Antarctica (Hindell & McMahon, 2000; Hofmeyr, 2015). Most adult females feed in pelagic zones, while adult males feed in both pelagic and benthic zones (Hindell et al., 1991). The diet of this pinniped includes different species of fish and squid, with changes that are proportional according to the season and feeding areas (Bradshaw et al., 2003). Southern elephant seals perform long-range movements, coupled with the absence of oceanographic barriers and currents that could hinder their displacement. This has resulted in relatively frequent records on the Brazilian coasts, with almost 50 individuals observed between 1958 and 2008 (de Moura et al., 2010). There are records of this species toward northern latitudes, whose frequency has increased recently or has been documented for the first time (e.g., Alava & Aurioles-Gamboa, 2017; Páez-Rosas et al., 2018; Elorriaga-Verplancken et al., 2020; de Vos, 2021; Alava et al., 2022). These unusually long-range movements by this species involve juvenile and subadult males, as these seem not to choose resting or hauling sites as selectively as older and more experienced animals (Mulaudzi et al., 2008). In this regard, the continental edge of the southeast Pacific is narrow and relatively close to the coast, which favors juveniles and subadults to move along this coast and its productive waters, heading to northern and distant latitudes (Acevedo et al., 2016). This article reports the presence of two Southern elephant seals on the coasts of Chiapas and Oaxaca, Mexico. Both individuals were taxonomically identified based on the large size of the specimens, compared with animals of the same sex and age class as the Northern elephant seal (M. angustirostris). Other useful features for identification included a thick neck relative to head size, and proboscis length and size which is shorter, smaller, and with nostrils tending to be more forward-facing compared to males of the Northern elephant seal, whose proboscis is much larger and rounded (Reeves et al., 2002; Páez-Rosas et al., 2018). The first individual was observed on 15 December 2020 at Santuario Playa, Puerto Arista (SPPA), 2.9 km southeast of the Puerto Arista town (15°55’41.96” N, 93°48’10.02” W; Fig. 1). Its presence was reported by the staff of the local turtle camp. The individual, which was molting, had no external injuries nor evidence of interaction with human activities such as fishing. The Southern elephant seal (Mirounga leonina) has a generally circumpolar distribution in the Southern Hemisphere. Four populations are distinguished based on their genetic attributes. One inhabits Argentina and Chile, including the Valdés Peninsula, the Falkland Islands, the Strait of Magellan, and the Chilean Antarctic region (Capella et al., 2017); the second ranges in the Atlantic Ocean along South Georgia, South Orkney, South Shetland, Bouvetøya, and Gough islands; the third, in the Indian Ocean on the Kerguelen, Crozet, Heard, and Prince Edward islands; an
南极洲(Hindell & McMahon, 2000;Hofmeyr, 2015)。大多数成年雌性在远洋区觅食，而成年雄性在远洋区和底栖区都觅食(Hindell et al.， 1991)。这种鳍状动物的饮食包括不同种类的鱼类和鱿鱼，并根据季节和喂养区域的不同而成比例地变化(Bradshaw et al.， 2003)。南象海豹进行远距离移动，再加上没有海洋屏障和可能阻碍它们迁移的洋流。这导致了巴西海岸相对频繁的记录，1958年至2008年期间观察到近50只个体(de Moura et al.， 2010)。该物种在北纬地区有记录，其频率最近有所增加或首次被记录(例如，Alava & Aurioles-Gamboa, 2017;Páez-Rosas等人，2018;Elorriaga-Verplancken et al.， 2020;de Vos, 2021;Alava et al.， 2022)。这个物种的这些不寻常的长距离运动涉及幼年和亚成年雄性，因为它们似乎不像年长和更有经验的动物那样有选择性地选择休息或搬运地点(Mulaudzi et al, 2008)。在这方面，东南太平洋的大陆边缘狭窄且相对靠近海岸，这有利于幼鱼和亚成鱼沿着海岸及其生产水域移动，前往北部和遥远的纬度(Acevedo et al.， 2016)。这篇文章报道了两只南部象海豹在墨西哥恰帕斯州和瓦哈卡州海岸的存在。根据标本的大尺寸，将这两个个体与与北方象海豹(M. angustirostris)相同性别和年龄类别的动物进行了分类鉴定。其他有用的识别特征包括相对于头部大小的粗脖子，与北方象海豹的雄性相比，前者的鼻长和大小更短、更小，鼻孔更朝前(北方象海豹的鼻长更大、更圆)(Reeves et al.， 2002;Páez-Rosas et al.， 2018)。第一个个体于2020年12月15日在Puerto Arista (SPPA)的Santuario Playa观测到，位于Puerto Arista镇东南2.9公里处(15°55 ' 41.96 " N, 93°48 ' 10.02 " W;图1)当地海龟营地的工作人员报告了它的存在。这只正在换毛的个体没有外伤，也没有与捕鱼等人类活动相互作用的证据。南象海豹(miounga leonina)在南半球一般是绕极分布的。根据它们的遗传属性来区分四个种群。一个居住在阿根廷和智利，包括瓦尔德萨梅斯半岛、福克兰群岛、麦哲伦海峡和智利南极地区(Capella et al.， 2017);第二个分布在大西洋，沿南乔治亚岛、南奥克尼岛、南设得兰岛、布韦特岛和戈夫岛分布;第三个是在印度洋的克格伦岛、克罗泽岛、赫德岛和爱德华王子岛;第四种是在太平洋上靠近新西兰的麦克夸尔岛、坎贝尔岛和安提波德岛(Slade et al.， 1998)。据估计，2000年该物种的总种群规模约为75万只(Hindell等人，2016;Hindell, 2018)，该物种被国际自然保护联盟列为“最不受关注”(Hofmeyr, 2015)。南象海豹主要在南纬40°和南纬40°之间觅食
{"title":"Records of Southern elephant seals (Mirounga leonina) in the southern Mexican Pacific","authors":"Arturo Romero-Tenorio, Fernando R Elorriaga Verplancken, J. Gallo‐Reynoso, Luis Arturo Álvarez-Márquez, Isai D. Barba‐Acuña","doi":"10.5597/lajam00311","DOIUrl":"https://doi.org/10.5597/lajam00311","url":null,"abstract":"Antarctica (Hindell & McMahon, 2000; Hofmeyr, 2015). Most adult females feed in pelagic zones, while adult males feed in both pelagic and benthic zones (Hindell et al., 1991). The diet of this pinniped includes different species of fish and squid, with changes that are proportional according to the season and feeding areas (Bradshaw et al., 2003). Southern elephant seals perform long-range movements, coupled with the absence of oceanographic barriers and currents that could hinder their displacement. This has resulted in relatively frequent records on the Brazilian coasts, with almost 50 individuals observed between 1958 and 2008 (de Moura et al., 2010). There are records of this species toward northern latitudes, whose frequency has increased recently or has been documented for the first time (e.g., Alava & Aurioles-Gamboa, 2017; Páez-Rosas et al., 2018; Elorriaga-Verplancken et al., 2020; de Vos, 2021; Alava et al., 2022). These unusually long-range movements by this species involve juvenile and subadult males, as these seem not to choose resting or hauling sites as selectively as older and more experienced animals (Mulaudzi et al., 2008). In this regard, the continental edge of the southeast Pacific is narrow and relatively close to the coast, which favors juveniles and subadults to move along this coast and its productive waters, heading to northern and distant latitudes (Acevedo et al., 2016). This article reports the presence of two Southern elephant seals on the coasts of Chiapas and Oaxaca, Mexico. Both individuals were taxonomically identified based on the large size of the specimens, compared with animals of the same sex and age class as the Northern elephant seal (M. angustirostris). Other useful features for identification included a thick neck relative to head size, and proboscis length and size which is shorter, smaller, and with nostrils tending to be more forward-facing compared to males of the Northern elephant seal, whose proboscis is much larger and rounded (Reeves et al., 2002; Páez-Rosas et al., 2018). The first individual was observed on 15 December 2020 at Santuario Playa, Puerto Arista (SPPA), 2.9 km southeast of the Puerto Arista town (15°55’41.96” N, 93°48’10.02” W; Fig. 1). Its presence was reported by the staff of the local turtle camp. The individual, which was molting, had no external injuries nor evidence of interaction with human activities such as fishing. The Southern elephant seal (Mirounga leonina) has a generally circumpolar distribution in the Southern Hemisphere. Four populations are distinguished based on their genetic attributes. One inhabits Argentina and Chile, including the Valdés Peninsula, the Falkland Islands, the Strait of Magellan, and the Chilean Antarctic region (Capella et al., 2017); the second ranges in the Atlantic Ocean along South Georgia, South Orkney, South Shetland, Bouvetøya, and Gough islands; the third, in the Indian Ocean on the Kerguelen, Crozet, Heard, and Prince Edward islands; an","PeriodicalId":17967,"journal":{"name":"Latin American Journal of Aquatic Mammals","volume":"142 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2023-08-17","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"86451801","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
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