Marine Mammal Science最新文献

{"title":"Individual or Group Signatures? Stereotyped Whistle Contour Types by Free-Ranging Risso’s Dolphins","authors":"Raul Rio,&nbsp;Hiram Rosales Nanduca","doi":"10.1111/mms.70011","DOIUrl":"https://doi.org/10.1111/mms.70011","url":null,"abstract":"<div>\u0000 \u0000 <p>Individual recognition mechanisms have played a key role in odontocete ecology, maintaining social cohesion and therefore ensuring the maintenance of long-term social ties. The current study was the first to identify and describe stereotyped whistle contour types by both a visual similarity value judgment task and acoustic and temporal parameters in free-ranging Risso's dolphins (<i>Grampus griseus</i>) in Mexican Pacific waters of the Gulf of the California. In total, 64.1% (118) of all analyzed whistles (184) were classified as stereotyped whistles (STW); 82.2% of them (97) met the SIGnature IDentification bout criteria and were, subsequently, ascribed into one of the five possible signature whistle (PSW) types. These signature call types accounted for 52.7% (97/184) of the acoustic repertoire. All PSW types were classified as sine (wavering sinusoidal whistles) and showed mean acoustic and temporal variable values similar to other studies of Risso's dolphins that did not differentiate signature whistles (SWs). External naive independent observers who lacked expertise in bioacoustics have confirmed the adopted classification created at high agreement level and near perfect match. Accordingly, the present study provided additional acoustic evidence of individually distinct vocalization in this species, reinforcing the need for further studies to help deepen and broaden the knowledge about the function, production and incidence of individual and “group signatures” and cognitive and recognition processes in the herein investigated species, among others.</p>\u0000 </div>","PeriodicalId":18725,"journal":{"name":"Marine Mammal Science","volume":"41 3","pages":""},"PeriodicalIF":2.0,"publicationDate":"2025-03-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144519669","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Age and Length at Sexual Maturity, Calving Interval, and Ovarian Activity of Female Tamanend's Bottlenose Dolphins (Tursiops erebennus) in South Carolina Waters","authors":"Jori E. Graeff,&nbsp;Megan M. Krzewinski,&nbsp;Wayne E. McFee","doi":"10.1111/mms.70006","DOIUrl":"https://doi.org/10.1111/mms.70006","url":null,"abstract":"<div>\u0000 \u0000 <p>Tamanend's bottlenose dolphins (<i>Tursiops erebennus</i>) face population and environmental stressors that influence the age and length at sexual maturity (ASM and LSM, respectively) and calving interval, which are life history traits used to assess population status and health. We provide initial estimates of the ASM, LSM, and calving interval, as well as descriptions of ovarian activity of female Tamanend's bottlenose dolphins that stranded in South Carolina waters. ASM and LSM estimates were approximately 10 years and 215 cm, respectively. Analysis of carcasses sampled over a three-decade period (1992–2022) indicated temporal variations in maturation, possibly related to unusual mortality events and/or periods of poor animal health. Stranding location did not appear to influence maturation. The calving interval estimate averaged between 2 and 4 years. Corpora counts relevant to age supported previous findings of corpora accumulation in bottlenose dolphins. In mature females, the left ovary accumulated more corpora and generally weighed more than the right ovary, suggesting asymmetric ovarian activity. To support the conservation of this newly recognized coastal and estuarine species, we suggest continued monitoring of the onset of sexual maturation and calving interval.</p>\u0000 </div>","PeriodicalId":18725,"journal":{"name":"Marine Mammal Science","volume":"41 3","pages":""},"PeriodicalIF":2.0,"publicationDate":"2025-03-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144519667","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Killer Whale (Orcinus orca) Opportunistic Predation Events on Whale Sharks (Rhincodon typus) in the Eastern Tropical Pacific","authors":"Hernán Orellana-Vásquez,&nbsp;Galo Echeverría,&nbsp;Jacob Moscoso,&nbsp;Santiago Díaz-Pazmiño,&nbsp;Daniela Alarcón-Ruales","doi":"10.1111/mms.70007","DOIUrl":"https://doi.org/10.1111/mms.70007","url":null,"abstract":"","PeriodicalId":18725,"journal":{"name":"Marine Mammal Science","volume":"41 3","pages":""},"PeriodicalIF":2.0,"publicationDate":"2025-03-12","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144520123","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Distinct Fecal Microbiome Communities and Functional Predictions in Spotted Seals: Age-Dependent and Dietary Transformations","authors":"Yue Dong,&nbsp;Yuyao Sun,&nbsp;Qinzeng Xu,&nbsp;Yu Zang,&nbsp;Zhibo Yang,&nbsp;Guoxu Yu,&nbsp;Zhongxun Wu,&nbsp;Hui Xiao,&nbsp;Xuelei Zhang","doi":"10.1111/mms.70008","DOIUrl":"https://doi.org/10.1111/mms.70008","url":null,"abstract":"<div>\u0000 \u0000 <p>The spotted seal (\u0000 <i>Phoca largha</i>\u0000 ), which primarily inhabits the cold waters of the Northwest Pacific Ocean, including China's northern Bohai and Yellow Seas, exhibits age-related variations in its fecal microbiome that remain poorly understood. This study investigated the fecal microbiome composition and predicted functional capabilities between adult and juvenile spotted seals. Firmicutes was the dominant phylum in both groups, with significant differences in abundances of Firmicutes and Bacteroidota (<i>p</i> &lt; 0.05). Furthermore, higher taxonomic diversity was found in adults, with six dominant genera compared to three in juveniles. <i>Clostridium sensu stricto 1</i> and <i>UCG-005</i> were identified as core genera, whereas <i>Bacteroides</i> and <i>Peptoclostridium</i> were specific to adults and <i>\u0000 Eubacterium fissicatena group</i> and <i>Blautia</i> were specific to juveniles. Moreover, bacterial functional prediction revealed a significant enrichment (<i>p</i> &lt; 0.01) of the Transporters and ABC transporters pathways in juveniles, while the Ribosome pathway was abundant in adults (<i>p</i> &lt; 0.01). The adults’ fecal microbiome displayed more complex and stable bacterial interactions than that of juveniles. Additionally, phylogenetic analysis revealed that \u0000 <i>Clostridium perfringens</i>\u0000 in adults was distributed across marine and terrestrial mammals, whereas <i>Faecalicatena</i> in juveniles demonstrated high host specificity. These findings help to explain how age and diet shape the gut microbiome of marine mammals.</p>\u0000 </div>","PeriodicalId":18725,"journal":{"name":"Marine Mammal Science","volume":"41 3","pages":""},"PeriodicalIF":2.0,"publicationDate":"2025-03-09","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144519972","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"We Go Signaling Into the Night: Describing an Echolocation Signal of an Unknown Beaked Whale (Cetacea; Ziphiidae) off West Africa","authors":"Kiersten Lorraine Runte,&nbsp;Katie A. Kowarski,&nbsp;Julien J.-Y. Delarue,&nbsp;Emily E. Maxner,&nbsp;David Hedgeland,&nbsp;S. Bruce Martin","doi":"10.1111/mms.70002","DOIUrl":"https://doi.org/10.1111/mms.70002","url":null,"abstract":"<p>Beaked whales (<i>Cetacea; Ziphiidae</i>), one of the most diverse families of cetaceans, can be identified by species-specific, frequency-modulated echolocation signals. Of the 24 known species of beaked whales, over half have been assigned a unique signal type. A novel echolocation pulse belonging to an unknown beaked whale species was recorded off West Africa (Beaked Whale of West Africa, BWWA), along the coast of the Democratic Republic of São Tomé and Príncipe. Bottom-mounted autonomous acoustic recorders (sampling rate of 375 kHz) were deployed from October 2018 to August 2019 (294 recording days) at depths of 450–600 m. An automated detector-classifier created to identify BWWA (per file Precision of 1.00; Recall of 1.00)-guided manual validation. BWWA was present in all recording months and detected during local nighttime hours (98% of detections occurred during fully dark periods). BWWA had a 52.5 kHz median peak frequency, 55.4 kHz center frequency, 29.0 kHz −10 dB bandwidth, 843 μs duration, and 86 ms inter-pulse interval (IPI). While species identification remains unsolved for BWWA, spectral similarities to unidentified signals in the Pacific Ocean, BWC, and in the Gulf of Mexico, BWG, find that all three signals can be characterized by longer pulse durations and shorter IPIs.</p>","PeriodicalId":18725,"journal":{"name":"Marine Mammal Science","volume":"41 3","pages":""},"PeriodicalIF":2.0,"publicationDate":"2025-03-09","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://onlinelibrary.wiley.com/doi/epdf/10.1111/mms.70002","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144519929","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Understanding early ontogeny and whisker growth dynamics of Weddell seal (Leptonychotes weddellii) pups through stable isotope analysis","authors":"Danelle A. Baronia,&nbsp;Heather E. M. Liwanag,&nbsp;Linnea E. Pearson,&nbsp;Carolyn M. Kurle","doi":"10.1111/mms.13229","DOIUrl":"https://doi.org/10.1111/mms.13229","url":null,"abstract":"<p>Stable isotope analysis of animal tissues is a valuable tool for understanding foraging ecology, habitat use, and developmental changes throughout an animal's life. Stable isotope values of whisker segments offer long-term data on mammalian foraging, as whisker growth incorporates isotopic signals from the diet and reflects dietary shifts during events like birth and weaning. We estimated birth dates of 7-week-old Weddell seal (<i>Leptonychotes weddellii</i>) pups (<i>n</i> = 17) by analyzing stable carbon (<i>δ</i>\u0000 ¹³C) and nitrogen (<i>δ</i>\u0000 ¹⁵N) isotope values measured from sequentially sampled whisker segments to evaluate the technique's accuracy in predicting early developmental events. We also estimated prenatal and postnatal whisker growth rates to construct a timeline for each pup using the stable isotope values measured longitudinally along each whisker. All pups showed consistent trends in <i>δ</i>\u0000 ¹³C and <i>δ</i>\u0000 ¹⁵N values along the length of their whiskers, with no evidence of a weaning signal. Post-birth, <i>δ</i>\u0000 ¹⁵N values across the sequentially sampled segments of vibrissae steadily increased, likely reflecting the pups' dependence on maternal milk. The <i>δ</i>\u0000 ¹³C values remained mostly constant, suggesting that mothers did not forage far from their breeding colonies, and the <i>δ</i>\u0000 ¹⁵N values were similar across individual timelines, indicating that mothers occupied a narrow trophic range.</p>","PeriodicalId":18725,"journal":{"name":"Marine Mammal Science","volume":"41 3","pages":""},"PeriodicalIF":2.0,"publicationDate":"2025-03-06","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://onlinelibrary.wiley.com/doi/epdf/10.1111/mms.13229","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144519828","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Evaluating Tour Boat Compliance With Dolphin-Watching Guidelines in the Sian Ka'an Biosphere Reserve","authors":"Leslie Mariel Paredes-Torres,&nbsp;Delma Nataly Castelblanco-Martínez,&nbsp;Carlos A. Niño-Torres,&nbsp;Natalia Garcés-Cuartas,&nbsp;Eric Angel Ramos","doi":"10.1111/mms.70004","DOIUrl":"https://doi.org/10.1111/mms.70004","url":null,"abstract":"<div>\u0000 \u0000 <p>Boat-based dolphin-watching tourism targeting common bottlenose dolphins (<i>Tursiops truncatus</i>) in the Mexican Caribbean is an increasing activity. Yet, tour boat compliance with local dolphin-watching guidelines has not been evaluated, and the impacts of these activities on local dolphin populations remain unknown. To address this gap, we used boat-based observations and aerial drone video recordings to evaluate tour boat compliance and described bottlenose dolphins' behavioral responses. We assessed tour boat adherence to key local guidelines, including observation time limits, maintaining minimum distances from dolphins, limiting the number of vessels, and controlling vessel speeds during approach and departure. To describe the behavioral responses of dolphins during tour boat activity, we quantified changes in directional movement, group cohesion, and swimming speed during boat interactions. Our findings revealed that 98% of the observed dolphin-watching events (<i>n</i> = 323) were non-compliant, with the most frequent violation being the proximity to dolphins. During boat interactions, 95% of dolphin directional changes were movements away from boat trajectories and 55% showed increased swimming speeds. These results underscore the need for monitoring and enforcing compliance with guidelines in dolphin-watching tourism, aiming to develop strategies to ensure the sustainability of this local tourism practice.</p>\u0000 </div>","PeriodicalId":18725,"journal":{"name":"Marine Mammal Science","volume":"41 3","pages":""},"PeriodicalIF":2.0,"publicationDate":"2025-03-06","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144519827","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Regular Presence of Harbor Porpoises in the Northern Alborán Sea","authors":"Samantha Blakeman,&nbsp;Juan Manuel Salazar,&nbsp;Noelia Villalba,&nbsp;Antonio Segura,&nbsp;Elena Papale,&nbsp;Mel Cosentino","doi":"10.1111/mms.70005","DOIUrl":"https://doi.org/10.1111/mms.70005","url":null,"abstract":"<p>The harbor porpoise (<i>Phocoena phocoena</i>) in the Atlantic waters of Spain and Portugal are a genetically differentiated population from the rest of the North Atlantic. They are rarely seen on the southern Atlantic coast of Spain and are thought to be extinct in the Mediterranean Sea, with scattered sightings and strandings recorded along the Spanish Mediterranean coast. Here, we present 35 live sightings of harbor porpoises along a ~15 km coastline between Los Boliches (Fuengirola) and Benalmádena in Andalucia. The data were collected from whale watching vessels in two distinct periods: 2011–2013 and 2015–2019. The sightings included single individuals (20%) and groups of to up to 6 animals, including calves (especially in 2019). In one encounter, the animals were harassed by people on jet skis. The presence of porpoises and threats they face in this relatively narrow area highlight the need to implement conservation efforts and increase protection.</p>","PeriodicalId":18725,"journal":{"name":"Marine Mammal Science","volume":"41 3","pages":""},"PeriodicalIF":2.0,"publicationDate":"2025-03-06","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://onlinelibrary.wiley.com/doi/epdf/10.1111/mms.70005","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144519826","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Whisker growth dynamics of walrus under human care","authors":"Danielle Blackfield,&nbsp;Erika L. Allen,&nbsp;Nick Northcraft,&nbsp;Sydney E. Pitts,&nbsp;Ashley Pratt-Smith,&nbsp;Mitzi Synnott,&nbsp;Heather Broughton,&nbsp;Brianna R. Beechler,&nbsp;Shea Steingass","doi":"10.1111/mms.70000","DOIUrl":"https://doi.org/10.1111/mms.70000","url":null,"abstract":"&lt;p&gt;Wildlife species that live in remote habitats often require significant investment for scientific study. As such, in lieu of direct observation, conservation research often relies on the analysis of biological samples that are easier to access (feces, hair, whiskers) to gain insight into a wild species' life history (Crawford et al., &lt;span&gt;2008&lt;/span&gt;). Using these samples, scientists can explore exposure to toxic elements, stress, foraging behavior, and even spatial habitat use without undue stress to the animal itself (Crawford et al., &lt;span&gt;2008&lt;/span&gt;). Whiskers (also known as vibrissae), and other keratinized tissues, can be analyzed via isotopic analysis for their content of elements, hormones, and isotopes that remain stable over time. These analyses provide longitudinal insight into an animal's stress, exposure to pollutants, diet, foraging habits, habitat use, and health that can be essential for wildlife managers and scientists alike (Ceia et al., &lt;span&gt;2018&lt;/span&gt;; Charapata et al., &lt;span&gt;2022&lt;/span&gt;; Crawford et al., &lt;span&gt;2008&lt;/span&gt;; Jones et al., &lt;span&gt;2020&lt;/span&gt;; Keogh et al., &lt;span&gt;2021&lt;/span&gt;; Kooyomjian et al., &lt;span&gt;2022&lt;/span&gt;). Whiskers can be obtained from both living and dead animals through minimally invasive sampling efforts, making them an ideal tool for tracking long-term biological processes and ecological effects on individuals.&lt;/p&gt;&lt;p&gt;The behavior of semi-aquatic marine mammal species can be difficult to directly observe because they spend much of their time in the marine environment. Pacific walruses (&lt;i&gt;Odobenus rosmarus divergens&lt;/i&gt;) are one such species. In combination with annual long-distance seasonal migrations up to 3000 km, dives as deep as 130 m, and haulouts on remote sea ice, Pacific walruses spend much of their time in isolated environments that require indirect methods of study when compared to direct observation of terrestrial-based mammals (Finley &amp; Renaud, &lt;span&gt;1980&lt;/span&gt;; Kastelein, &lt;span&gt;2008&lt;/span&gt;). What is more, as suitable habitat continues to shift in the face of sea ice loss from a warming climate, and adaptive behaviors necessitate focus on new habitats and prey sources, understanding walrus life history has become paramount to understand conservation targets (Couch et al., &lt;span&gt;2022&lt;/span&gt;).&lt;/p&gt;&lt;p&gt;Isotopic analysis of walrus whiskers has been proposed as one such tool to circumvent the above challenges while meeting conservation research objectives. However, while there is a range of information that can be determined from whiskers, much of the current research has lacked the ability to determine chronology because growth rates of walruses whiskers have not yet been estimated. Walrus whisker growth cannot be extrapolated from other pinniped species, as growth models vary among species, with some species' whiskers displaying linear growth, while others display asymptotic growth (McHuron et al., &lt;span&gt;2016&lt;/span&gt;). The purpose of this study was to fill this gap in knowledge for fu","PeriodicalId":18725,"journal":{"name":"Marine Mammal Science","volume":"41 3","pages":""},"PeriodicalIF":2.0,"publicationDate":"2025-02-22","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://onlinelibrary.wiley.com/doi/epdf/10.1111/mms.70000","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144519922","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Habitat Preference of Risso's Dolphins (Grampus griseus) off the South Coast of Portugal","authors":"Miguel P. Martins,&nbsp;Fábio L. Matos,&nbsp;André Cid,&nbsp;Guilherme Estrela,&nbsp;Alicia Quirin,&nbsp;Francisco O. Borges,&nbsp;Joana Castro","doi":"10.1111/mms.70001","DOIUrl":"https://doi.org/10.1111/mms.70001","url":null,"abstract":"<div>\u0000 \u0000 <p>Information on the occurrence and ecology of Risso's dolphins off the southern coast of Portugal is limited and poorly understood. This study investigated the occurrence of this species in the Algarve via presence-absence models. In total 63 Risso's dolphin sightings were recorded with an average group size of 10 animals and a presence of immature animals in most groups (73.02%). Generalized Additive Models were fitted to test how static and dynamic oceanographic variables affected Risso's dolphin occurrence between 2010 and 2020, from a presence-absence dataset. The optimal model showed that Risso's dolphins' probability of occurrence was higher close to the coast, and positively related to sea surface temperature, reaching a maximum presence probability between 22°C and 24°C. A positive but nonsignificant relationship between chlorophyll-a concentration with 1 month time lag and Risso's dolphin presence was also detected. This study provides a first step to understanding habitat preference of Risso's dolphins in the south of Portugal and identifies this area's importance for the species.</p>\u0000 </div>","PeriodicalId":18725,"journal":{"name":"Marine Mammal Science","volume":"41 3","pages":""},"PeriodicalIF":2.0,"publicationDate":"2025-02-17","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144519848","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}