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A new species of baleen whale (Balaenoptera) from the Gulf of Mexico, with a review of its geographic distribution Mar. Mamm. Sci. (IF 1.651) Pub Date : 2021-01-10 Patricia E. Rosel; Lynsey A. Wilcox; Tadasu K. Yamada; Keith D. Mullin
Bryde's‐like whales are a complex of medium‐sized baleen whales that occur in tropical waters of all three major ocean basins. Currently, a single species of Bryde's whale, Balaenoptera edeni Anderson, 1879, is recognized, with two subspecies, Eden's whale, B. edeni edeni and Bryde's whale, B. edeni brydei (Olsen, 1913), although some authors have recognized these as separate species. Recently, a new
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Gear modifications reduced humpback whale entanglements in a commercial rock lobster fishery Mar. Mamm. Sci. (IF 1.651) Pub Date : 2021-01-07 Jason R. How; William K. de la Mare; Douglas K. Coughran; Michael C. Double; Simon de Lestang
Entanglement of whales in fishing gear occurs globally and where populations are recovering from past exploitation, entanglement frequency is likely to increase. The Western Australian population of humpback whales (Megaptera novaeangliae) is growing rapidly, yet from 1990 to 2010 the number of whales reported entangled in gear from the pot‐based western rock lobster fishery was relatively stable at
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Sink or swim: Risk stratification of preweaning mortality in harbor seal pups (Phoca vitulina richardii) admitted for rehabilitation Mar. Mamm. Sci. (IF 1.651) Pub Date : 2021-01-07 Justine Cole; David Fraser
To date, few consistent relationships between survival in rehabilitation programs and diagnostic measures recorded upon admission have been identified for harbor seal pups. Veterinary records for 718 unweaned Pacific harbor seal pups (Phoca vitulina richardii) admitted to a rehabilitation center were examined to identify clinical factors associated with preweaning survival and develop a triage tool
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Contrasting trends in gray seal (Halichoerus grypus) pup production throughout the increasing northwest Atlantic metapopulation Mar. Mamm. Sci. (IF 1.651) Pub Date : 2020-12-22 Cornelia E. den Heyer; W. Don Bowen; Julian Dale; Jean‐François Gosselin; Michael O. Hammill; David W. Johnston; Shelley L. C. Lang; Kimberly T. Murray; Garry B. Stenson; Stephanie A. Wood
The northwest Atlantic subspecies of gray seal (Halicheorus grypus grypus) has been increasing for more than a half century and has reestablished breeding colonies in Canadian and US waters. In 2016, visual, oblique, and vertical large‐format digital photographic surveys were conducted at all known breeding colonies in the northwest Atlantic. Total pup production in the northwest Atlantic was estimated
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Ontogenetic niche partitioning in southern elephant seals from Argentine Patagonia Mar. Mamm. Sci. (IF 1.651) Pub Date : 2020-12-12 Julieta Campagna; Mirtha N. Lewis; Victoria González Carman; Claudio Campagna; Christophe Guinet; Mark Johnson; Randall W. Davis; Diego H. Rodríguez; Mark A. Hindell
Elephant seals, Mirounga spp., are highly dimorphic, having different energetic requirements according to age and sex, and foraging in various ecological and oceanographic contexts. Resource partitioning has been shown for the sub‐Antarctic populations of southern elephant seals, M. leonina, where colonies are surrounded by narrow shelves that deepen abruptly. In contrast, seals from Península Valdés
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Bone mineral density of the common bottlenose dolphin radius: A primary skeletal site for clinical bone densitometry and preliminary descriptive data set using archival specimens Mar. Mamm. Sci. (IF 1.651) Pub Date : 2020-12-09 James W. B. Powell; Deborah A. Duffield; Jonathan J. Kaufman; Gangming Luo; Gretchen N. Lovewell; Wayne E. McFee
We examined bone mineral density (BMD) in the pectoral flipper of the common bottlenose dolphin, Tursiops truncatus. These data addressed the need to define a comprehensive target site for osteodensitometric assessment and to provide a descriptive bone density data set for this species. We analyzed 388 radii from 279 bottlenose dolphins using dual energy X‐ray absorptiometry (DXA), the accepted standard
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Patterns of mortality in endangered Cook Inlet beluga whales: Insights from pairing a long‐term photo‐identification study with stranding records Mar. Mamm. Sci. (IF 1.651) Pub Date : 2020-12-03 Tamara L. McGuire; Kim E. W. Shelden; Gina K. Himes Boor; Amber D. Stephens; John R. McClung; Christopher Garner; Caroline E. C. Goertz; Kathleen A. Burek‐Huntington; Greg O'Corry‐Crowe; Bruce Wright
Mortality is a demographic metric crucial for understanding the dynamics of endangered populations such as Cook Inlet beluga whales (CIBWs, Delphinapterus leucas), but patterns of mortality are currently not well understood for CIBWs, making decisions about recovery actions challenging. We combined long‐term photo‐ID data from approximately 420 individual belugas identified during the period 2005–2017
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Genetic evidence for seasonal consumption of monkfish (Lophius spp.) and salmonids (Salmo spp.) by gray seals Mar. Mamm. Sci. (IF 1.651) Pub Date : 2020-11-28 Mette K. Schiønning; Martha Gosch; Eileen Dillane; Michelle Cronin; Mark J. Jessopp
Recoveries of gray seal (Halichoerus grypus) populations across their eastern Atlantic distribution have led to a steady increase in seal‐fishery interactions. Fishers have estimated depredation of salmonids (Salmo spp.) and monkfish (Lophius spp.) as high as 40% and 59% respectively in Ireland. However, empirical evidence for the consumption of these species has been extremely limited due to diagnostic
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Reference values for serum chemistry of wild Amazon river dolphins (Inia geoffrensis) from the central Amazon Mar. Mamm. Sci. (IF 1.651) Pub Date : 2020-11-23 Daniela M. D. de Mello; Fabiana A. de Melo; Vera M. F. da Silva
Blood values of wild cetacean population are a valuable tool to drive proper management of threatened species. Reference intervals of 26 serum analytes were determined from 107 apparently healthy Amazon river dolphins (Inia geoffrensis) wild‐caught in the Mamirauá Sustainable Development Reserve (3°3′S, 64°51′W), central Amazon, Brazil. No differences were detected between males and females or between
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Sighting patterns reveal unobserved pupping events to revise reproductive rate estimates for Hawaiian monk seals in the main Hawaiian Islands Mar. Mamm. Sci. (IF 1.651) Pub Date : 2020-11-23 Stacie J. Robinson; Albert L. Harting; Tracy Mercer; Thea C. Johanos; Jason D. Baker; Charles L. Littnan
We used sighting reports, including decades of citizen‐reported Hawaiian monk seal (Neomonachus schauinslandi) sightings, to describe female breeding biology and reproductive success in the main Hawaiian Islands. We first used this data set to describe the timing of events in the female reproductive cycle. We then conducted an expert review of patterns in sighting histories to detect unobserved pupping
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A multidecadal Bayesian trend analysis of harbor porpoise (Phocoena phocoena) populations off California relative to past fishery bycatch Mar. Mamm. Sci. (IF 1.651) Pub Date : 2020-11-21 Karin A. Forney; Jeffrey E. Moore; Jay Barlow; James V. Carretta; Scott R. Benson
Harbor porpoises, Phocoena phocoena, off California, comprise four recognized population stocks: Morro Bay (MOR), Monterey Bay (MRY), San Francisco‐Russian River (SFRR), and Northern California‐Southern Oregon (NCSO). The three southernmost stocks experienced substantial bycatch in gill net fisheries during the 1970s and 1980s. While the SFRR stock received full protection from gill nets in 1989, the
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Environmental drivers of habitat use by common bottlenose dolphins (Tursiops truncatus) in the Indian River Lagoon, Florida, USA Mar. Mamm. Sci. (IF 1.651) Pub Date : 2020-11-21 Rachael Greller; Marilyn Mazzoli; Elizabeth Titcomb; Brandy Nelson; Richard Paperno; Scott H. Markwith
Anthropogenic impacts in estuarine systems can influence marine mammal habitat use, population dynamics, fitness, and mortality events. The objective was to examine habitat use among the resident common bottlenose dolphin (Tursiops truncatus) population inhabiting the Indian River Lagoon, Florida, and the influences of variation in environmental factors and prey availability in 2003–2015. We utilized
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CORRIGENDUM Mar. Mamm. Sci. (IF 1.651) Pub Date : 2020-11-12
In the manuscript, Castelblanco‐Martínez, D.N., Padilla‐Saldívar, J., Hernández‐Arana, H.A., Slone, D.H., Reid, J.P., & Morales‐Vela, B. (2013). Movement patterns of Antillean manatees in Chetumal Bay (Mexico) and coastal Belize: A challenge for regional conservation. Marine Mammal Science, 29, E166‐E182. https://doi.org/10.1111/j.1748‐7692.2012.00602.x, there were errors in the following elements:
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Creation of accurate 3D models of harbor porpoises (Phocoena phocoena) using 3D photogrammetry Mar. Mamm. Sci. (IF 1.651) Pub Date : 2020-11-11 Duncan J. Irschick; Johnson Martin; Ursula Siebert; Jakob H. Kristensen; Peter T Madsen; Fredrik Christiansen
Creating accurate 3D models of marine mammals is valuable for assessment of body condition, computational fluids dynamics models of locomotion, and for education. However, the methods for creating 3D models are not well‐developed. We used photography and video to create 3D photogrammetry models of harbor porpoises (Phocoena phocoena). We accessed one live adult female (155.5 cm total length), and two
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A review of big data analysis methods for baleen whale passive acoustic monitoring Mar. Mamm. Sci. (IF 1.651) Pub Date : 2020-11-08 Katie A. Kowarski; Hilary Moors‐Murphy
Many organizations collect large passive acoustic monitoring (PAM) data sets that need to be efficiently and reliably analyzed. To determine appropriate methods for effective analysis of big PAM data sets, we undertook a literature review of baleen whale PAM analysis methods. Methodologies from 166 studies (published between 2000–2019) were summarized, and a detailed review was performed on the 94
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Shallow‐water habitat use and population parameters of rough‐toothed dolphins, Steno bredanensis (G. Cuvier in Lesson, 1828) in southeastern Brazil Mar. Mamm. Sci. (IF 1.651) Pub Date : 2020-11-02 Rafael R. Carvalho; José Lailson‐Brito; Maja Kajin; Carlos Eduardo P. Quintana; Karina S. Pereira; Tatiana L. Bisi; Haydée A. Cunha; Alexandre F. Azevedo
The rough‐toothed dolphin (Steno bredanensis) is a poorly known species along its distribution especially in the Southern Hemisphere where data on habitat use and population parameters are scarce. Boat‐based surveys were conducted from 2009 to 2017 in a shallow water environment in southeastern Brazil. During focal‐group observations, S. bredanensis was more commonly found in mean depths of 22 m with
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Environmental factors influencing eastern North Pacific gray whale calf production 1994–2016 Mar. Mamm. Sci. (IF 1.651) Pub Date : 2020-10-30 Wayne L. Perryman; Trevor Joyce; David W. Weller; John W. Durban
This paper describes the relationship between eastern North Pacific gray whale calf production and environmental conditions in the Pacific Arctic where they feed. The results show how interannual variation in sea ice cover in the Bering and Chukchi Seas along with broader indices of North Pacific climate, such as Pacific Decadal Oscillation (PDO) and North Pacific Index (NPI), are linked to variation
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Body growth of North Atlantic right whales (Eubalaena glacialis) revisited Mar. Mamm. Sci. (IF 1.651) Pub Date : 2020-10-27 Sarah M. E. Fortune; Michael J. Moore; Wayne L. Perryman; Andrew W. Trites
Knowing size‐at‐age is important for determining food requirements and making inferences about the nutritional status of individuals and their populations. Accurate growth curves are also needed to quantify drug dosages to treat wounded or entangled animals. However, body sizes are often based on small numbers of measured animals that must be improved as new data become available. We updated an existing
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Demographic parameters of a free‐ranging deep‐diving cetacean, the long‐finned pilot whale Mar. Mamm. Sci. (IF 1.651) Pub Date : 2020-10-21 Philippe Verborgh; Pauline Gauffier; Ruth Esteban; Renaud de Stephanis
Demographic parameters provide baselines to estimate future population trajectories which can then be used in management decisions. The aim here was to estimate demographic parameters of long‐finned pilot whale (Globicephala melas) from the Strait of Gibraltar by fitting mark‐recapture models to photo‐identification data of primary and secondary marked individuals. These parameters were used to forecast
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Assessing the lethality of ship strikes on whales using simple biophysical models Mar. Mamm. Sci. (IF 1.651) Pub Date : 2020-10-12 Dan E. Kelley; James P. Vlasic; Sean W. Brillant
Studies of ship strikes on whales often focus on large vessels (>20 m), with attention to their speeds and the resulting risk of lethality. Smaller coastal vessels also co‐occur with whales, resulting in collisions that merit study. To cast light on injuries caused by vessels of all sizes, we used knowledge of right whale anatomy and Newtonian mechanics to construct simple models that predict the mechanical
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Age‐related differences in gut microbial community composition of captive spotted seals (Phoca largha) Mar. Mamm. Sci. (IF 1.651) Pub Date : 2020-08-10 Jiashen Tian; Jing Du; Jiabo Han; Xinran Song; Zhichuang Lu
Age is an important factor that significantly impacts the gut microbiota of various mammals. Captive spotted seals (Phoca largha) provide an ideal opportunity to study how age affects their gut microbiota, excluding other environmental factors, which is a challenge when monitoring wildlife. Here, the bacterial composition of the feces of captive spotted seals from four age groups were analyzed; namely
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Physical maturity in common bottlenose dolphins (Tursiops truncatus) from Sarasota Bay, Florida Mar. Mamm. Sci. (IF 1.651) Pub Date : 2020-09-17 Rebeccah A. Hazelkorn; Randall S. Wells; Zachary A. Siders; Ruth DeLynn; Gretchen N. Lovewell
Cetacean physical maturity is defined by growth cessation and complete fusion of epiphyses to vertebral bodies indicated by invisible sutures. Many studies have shown epiphyseal fusion is highly variable among individuals. In‐depth examinations into fusion variability are lacking. We analyzed vertebrae of 37 (n = 21 female, n = 16 male) stranded common bottlenose dolphins (Tursiops truncatus) from
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A comparison of Northeast Atlantic killer whale (Orcinus orca) stereotyped call repertoires Mar. Mamm. Sci. (IF 1.651) Pub Date : 2020-10-05 Anna Selbmann; Volker B. Deecke; Ivan D. Fedutin; Olga A. Filatova; Patrick J. O. Miller; Jörundur Svavarsson; Filipa I. P. Samarra
Killer whale call repertoires can provide information on social connections among groups and populations. Killer whales in Iceland and Norway exhibit similar ecology and behavior, are genetically related, and are presumed to have been in contact before the collapse of the Atlanto‐Scandian herring stock in the 1960s. However, photo‐identification suggests no recent movements between Iceland and Norway
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Age estimation and growth layer patterns in teeth of crabeater seals: A comparison of techniques Mar. Mamm. Sci. (IF 1.651) Pub Date : 2020-10-03 Julieta Cebuhar; Javier Negrete; Silvina Botta
Age estimation of marine mammals provides important information about ecological and life history parameters. Counting growth layer groups (GLGs) in the dentine and cementum of teeth is the most common technique for age estimation in pinnipeds. In this study, we used acid‐etched canines (n = 38) and decalcified stained postcanine sections (n = 40) to calibrate readings in mummified crabeater seals
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Variation in trophic resources in female South American sea lions at a small geographic scale Mar. Mamm. Sci. (IF 1.651) Pub Date : 2020-10-03 M. Florencia Grandi; Damián G. Vales; Enrique A. Crespo; Rocío Loizaga
Difference among colonies in the population structure of otariids can be driven by philopatry and/or by specializations in the foraging ecology of females. In northern Patagonia, the South American sea lion (SASL) shows some degree of spatial genetic structure among colonies from north and south zones. This study aims to explore the isotopic niche of SASL females in the last period of the pregnancy
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Abundance, survival, and annual rate of change of Cuvier's beaked whales (Ziphius cavirostris) on a Navy sonar range Mar. Mamm. Sci. (IF 1.651) Pub Date : 2020-09-22 K. Alexandra Curtis; Erin A. Falcone; Gregory S. Schorr; Jeffrey E. Moore; David J. Moretti; Jay Barlow; Erin Keene
Bayesian mark‐recapture estimates of survival, abundance, and trend are reported for Cuvier's beaked whales (Ziphius cavirostris) using a Navy training range off southern California. The deep‐diving beaked whale family is exceptionally vulnerable to mid‐frequency active sonar (MFAS), which has been implicated in mass strandings and altered foraging behavior. Extremely low sighting probabilities impede
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Sex ratios in blue whales from conception onward: effects of space, time, and body size Mar. Mamm. Sci. (IF 1.651) Pub Date : 2020-09-19 Trevor A. Branch; Cole C. Monnahan
Deviations from equal sex ratios in mammals can reveal insights into sex‐specific growth, survival, movements, and behavior. We assessed blue whale (Balaenoptera musculus) sex ratios based on 21,542 fetal and 311,901 whaling records, finding that males were slightly but significantly more common than females (51.3% fetal, 52.1% postnatal). Antarctic catches shifted from 52.4% male before 1951 to 48
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Population‐level impacts of natural and anthropogenic causes‐of‐death for Hawaiian monk seals in the main Hawaiian Islands Mar. Mamm. Sci. (IF 1.651) Pub Date : 2020-09-15 Albert L. Harting; Michelle M. Barbieri; Jason D. Baker; Tracy A. Mercer; Thea C. Johanos; Stacie J. Robinson; Charles L. Littnan; Katie M. Colegrove; Dave S. Rotstein
Identifying, assessing, and ranking the impact of individual threats is fundamental to the conservation and recovery of rare and endangered species. In this analysis, we quantify not only the frequency of specific causes‐of‐death (CODs) among Main Hawaiian Island (MHI) monk seals, but also assess the impact of individual CODs on the intrinsic growth rate, λ, of the MHI population. We used gross necropsy
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Resting and swimming metabolic rates in juvenile walruses (Odobenus rosmarus) Mar. Mamm. Sci. (IF 1.651) Pub Date : 2020-09-14 David A. S. Rosen
Changes in Arctic ice conditions have raised concerns regarding potential impacts on energy expenditure and food requirements of walruses. Modeling the repercussions of environmental changes requires accurate species‐specific measures of bioenergetic expenditures. This is particularly true for walruses, who have a unique anatomy and foraging ecology from other pinnipeds. This study measured resting
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Occurrence of Indo‐Pacific bottlenose dolphins (Tursiops aduncus) off the Wild Coast of South Africa using photographic identification Mar. Mamm. Sci. (IF 1.651) Pub Date : 2020-09-13 Michelle Caputo; Thibaut Bouveroux; Pierre William Froneman; Titus Shaanika; Stephanie Plön
The present study represents the first reported boat‐based photographic identification study of Indo‐Pacific bottlenose dolphins (Tursiops aduncus) off the Wild Coast of southeast South Africa. This area is known for the annual sardine run, which attracts apex predators to the region during the austral winter. Dedicated photo‐identification surveys were conducted along this coast at three different
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Interannual differences in postrelease movements of rehabilitated harbor seal pups (Phoca vitulina richardii) in the Salish Sea Mar. Mamm. Sci. (IF 1.651) Pub Date : 2020-09-05 Samantha Sangster; Martin Haulena; Chad Nordstrom; Joseph K. Gaydos
Despite the large number of harbor seals (Phoca vitulina richardii) rehabilitated worldwide, few studies have been conducted on postrelease movement and behavior of rehabilitated harbor seal pups. We compared interannual differences in movements and survival of 24 rehabilitated seal pups released in the Salish Sea in 2010 (n = 10), 2012 (n = 5), 2013 (n = 5), and 2014 (n = 4). We also compared the
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Distributional patterns of humpback whales (Megaptera novaeangliae) along the Newfoundland East Coast reflect their main prey, capelin (Mallotus villosus) Mar. Mamm. Sci. (IF 1.651) Pub Date : 2020-09-05 Kelsey F. Johnson; Gail K. Davoren
On the Newfoundland foraging ground, humpback whales (Megaptera novaeangliae) primarily consume capelin (Mallotus villosus), which experienced a population collapse in the early 1990s, associated with altered timing of spawning and spawning migration. We examined whether humpback whale movement and distribution match these prey changes. Combining tour company whale sighting reports and photographs
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The impact of temperature at depth on estimates of thermal habitat for short‐finned pilot whales Mar. Mamm. Sci. (IF 1.651) Pub Date : 2020-09-05 Stephanie K. Adamczak; William A. McLellan; Andrew J. Read; Christopher L. P. Wolfe; Lesley H. Thorne
Short‐finned pilot whales (Globicephala macrorhynchus) experience dramatic changes in temperature during deep dives, but studies of pilot whale habitat use typically rely solely on surface temperature measurements. We quantified vertically integrated thermal habitat for short‐finned pilot whales using a novel metric, degree‐hours, developed using data from digital acoustic recording tags (DTAGs) deployed
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Skin lesion prevalence of estuarine common bottlenose dolphins (Tursiops truncatus) in North Carolina, with comparisons to other east coast study sites Mar. Mamm. Sci. (IF 1.651) Pub Date : 2020-08-31 J. S. Taylor; L. B. Hart; J. Adams
Common bottlenose dolphins (Tursiops truncatus) are sentinels of environmental health. Skin lesions may indicate disease and can be used to infer population health. We estimated the prevalence of skin lesions and identified major lesion types on coastal bottlenose dolphins in Roanoke Sound, North Carolina, over a 3‐year period using photo‐identification. Boat‐based surveys were conducted from April
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Vocalizations of bearded seals (Erignathus barbatus) and their influence on the soundscape of the western Canadian Arctic Mar. Mamm. Sci. (IF 1.651) Pub Date : 2020-08-29 Annika F. Heimrich; William D. Halliday; Héloïse Frouin‐Mouy; Matthew K. Pine; Francis Juanes; Stephen J. Insley
The soundscape is a crucial habitat feature for marine mammals. This study investigates the contribution of bearded seal vocalizations to the soundscape in the western Canadian Arctic, and also the vocal characteristics of bearded seals relative to sea ice conditions. Passive acoustic data were recorded near Sachs Harbour between August 2015 and July 2016. Sound pressure levels (SPL) in the 50–1,000 Hz
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Bottlenose dolphins (Tursiops truncatus) in North Dalmatia, Croatia: Occurrence and demographic parameters Mar. Mamm. Sci. (IF 1.651) Pub Date : 2020-08-29 Grgur Pleslić; Nikolina Rako‐Gospić; Draško Holcer
The common bottlenose dolphin (Tursiops truncatus) population along the eastern Adriatic coast is believed to comprise discrete communities, yet many of them are unstudied. This study provides the first description of occurrence and demographic parameters for the community inhabiting waters of North Dalmatia. Dedicated boat‐based surveys conducted in summer months from 2013 to 2017 resulted in 13,896 km
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Captive environment influences the composition and diversity of fecal microbiota in Indo‐Pacific bottlenose dolphins, Tursiops aduncus Mar. Mamm. Sci. (IF 1.651) Pub Date : 2020-08-28 Akihiko Suzuki; Koyuki Akuzawa; Kazunobu Kogi; Keiichi Ueda; Miwa Suzuki
Captive environments impact the microbiota of captive animals; however, the comparison of microbiota between wild and captive dolphins has been poorly investigated. To explore the impact of a captive environment, we characterized the fecal microbiota of nine wild and four captive Indo‐Pacific bottlenose dolphins, Tursiops aduncus, using a next‐generation sequencing and revealed differences in the fecal
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Anthropogenic injuries disrupt social associations of common bottlenose dolphins (Tursiops truncatus) in Sarasota Bay, Florida Mar. Mamm. Sci. (IF 1.651) Pub Date : 2020-08-24 Michelle R. Greenfield; Katherine A. McHugh; Randall S. Wells; Daniel I. Rubenstein
Social connectivity is important for measuring the fitness of common bottlenose dolphins (Tursiops truncatus). While interactions in fission‐fusion societies vary between individuals, studies show that repeated interactions enhance reproduction and foraging success. Injuries that potentially remove an individual from its association network may disrupt these interactions. Using data from the long‐term
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Niche overlap and diet composition of three sympatric coastal dolphin species in the southwest Atlantic Ocean Mar. Mamm. Sci. (IF 1.651) Pub Date : 2020-08-16 Clarissa R. Teixeira; Silvina Botta; Fábio G. Daura‐Jorge; Luiza B. Pereira; Seth D. Newsome; Paulo C. Simões‐Lopes
Sympatric species are expected to differ in ecological requirements to minimize niche overlap and avoid competition. Here we assess the trophic interactions among three coexisting dolphin species from southern Brazil: the franciscana dolphin (Pontoporia blainvillei), the Guiana dolphin (Sotalia guianensis), and the Lahille's bottlenose dolphin (Tursiops truncatus gephyreus). We evaluated temporal variation
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Feeding ecology of the highly threatened common bottlenose dolphin of the Gulf of Ambracia, Greece, through stable isotope analysis Mar. Mamm. Sci. (IF 1.651) Pub Date : 2020-08-09 Asunción Borrell; Morgana Vighi; Tilen Genov; Ioannis Giovos; Joan Gonzalvo
The Gulf of Ambracia, in northwestern Greece, hosts a highly threatened community of about 150 common bottlenose dolphins (Tursiops truncatus). Until now, information on their feeding habits was derived exclusively from fish scale samples collected during surface‐feeding events targeting small schooling epipelagic fish. The aim of this study was to determine the diet of bottlenose dolphins living in
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Developing protocols for in‐water morphometric measurements of cetaceans using stereo‐videogrammetry Mar. Mamm. Sci. (IF 1.651) Pub Date : 2020-08-06 Suzanne K. Hillcoat; Matthew I. Curnock; Naomi M. Gardiner; R. Alastair Birtles
Morphometry underpins the basic knowledge of any organism's population demographics and dynamics. Such understanding enables the investigation of trends with important conservation implications including monitoring the health of individuals and changes in population dynamics over time. By detecting declines in health prior to the onset of significant mortality, monitoring of body condition can potentially
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Recommendations for estimating mark rate of cetaceans in photo‐ID research: A critique of field sampling protocols and variance estimation Mar. Mamm. Sci. (IF 1.651) Pub Date : 2020-08-03 Lindsay Wickman; William Rayment; Elisabeth Slooten; Stephen M. Dawson
Mark rate, or the proportion of the population with unique, identifiable marks, must be determined in order to estimate population size from photographic identification data. In this study we address field sampling protocols and estimation methods for robust estimation of mark rate and its uncertainty in cetacean populations. We present two alternatives for estimating the variance of mark rate: (1)
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DNA metabarcoding of feces to infer summer diet of Pacific walruses Mar. Mamm. Sci. (IF 1.651) Pub Date : 2020-07-24 Sarah A. Sonsthagen; Chadwick V. Jay; Robert S. Cornman; Anthony S. Fischbach; Jacqueline M. Grebmeier; Sandra L. Talbot
Environmental conditions in the Chukchi Sea are changing rapidly and may alter the abundance and distribution of marine species and their benthic prey. We used a metabarcoding approach to identify potentially important prey taxa from Pacific walrus (Odobenus rosmarus divergens) fecal samples (n = 87). Bivalvia was the most dominant class of prey (66% of all normalized counts) and occurred in 98% of
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Maximum entropy model: Estimating the relative suitability of cetacean habitat in the northern Savu Sea, Indonesia Mar. Mamm. Sci. (IF 1.651) Pub Date : 2020-07-20 Mochamad Iqbal Herwata Putra; Putu Liza Kusuma Mustika
An understanding of cetacean distribution is necessary to gain insights into crucial ecological processes for species conservation management. However, cetacean habitat preference and distribution in the northern Savu Sea, Indonesia, are still poorly understood. We use maximum entropy modeling with five environmental predictors to describe habitat preference and distribution of seven cetacean species
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Reproductive parameters of franciscana dolphins (Pontoporia blainvillei) of Southeastern Brazil Mar. Mamm. Sci. (IF 1.651) Pub Date : 2020-07-18 Débora F. Silva; Rodrigo A. Barbosa; Valéria R. M. Conversani; Silvina Botta; Aleta A. Hohn; Marcos C. de O. Santos
Reproductive parameters of 168 franciscana dolphins, Pontoporia blainvillei (73 females and 95 males) incidentally caught (n = 163) or stranded (n = 5) between 2005 and 2016 in southeastern Brazil are presented. Ovarian macroscopic analysis revealed 55 immature (75.3%) and 18 mature (24.7%) females. Annual pregnancy rate was estimated to be 0.36, with a calving interval of 2.8 years. Testicular histology
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Ecological implications of unprecedented warm water anomalies on interannual prey preferences and foraging areas of Guadalupe fur seals Mar. Mamm. Sci. (IF 1.651) Pub Date : 2020-07-18 María José Amador‐Capitanachi; Xchel G. Moreno‐Sánchez; Phalom Denohi Ventura‐Domínguez; Ariadna Juárez‐Ruiz; Eduardo González‐Rodríguez; Casandra Gálvez; Tenaya Norris; Fernando R. Elorriaga‐Verplancken
The Guadalupe fur seal (GFS) currently is recovering from near extinction and prey availability is an important factor. Scat and stable isotope analyses (SIA) were used to assess GFS foraging on Guadalupe Island during 2013–2016. This period was characterized by normal (2013) ocean temperatures followed by warm conditions (2014–2016). Scat samples (~40/year) were collected for prey identification.
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Common bottlenose dolphin (Tursiops truncatus) social structure and distribution changes following the 2008 Unusual Mortality Event in the Indian River Lagoon, Florida Mar. Mamm. Sci. (IF 1.651) Pub Date : 2020-07-17 Kristin Brightwell; Elizabeth Murdoch Titcomb; Marilyn Mazzoil; Quincy Gibson
In animal societies with fission‐fusion dynamics, demographic disturbances can influence the social and spatial structure of the population. Within the Indian River Lagoon (IRL), Florida, common bottlenose dolphins (Tursiops truncatus) have experienced recurrent unusual mortality events (UMEs) providing an opportunity to examine postdisturbance population and social cluster restructuring. This study
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Occurrence, site fidelity, and associations of oceanic common bottlenose dolphins (Tursiops truncatus) off northeastern New Zealand Mar. Mamm. Sci. (IF 1.651) Pub Date : 2020-07-04 Jochen R. Zaeschmar; Gabriela Tezanos‐Pinto; Sarah L. Dwyer; Catherine H. Peters; Jo Berghan; David Donnelly; Anna M. Meissner; Ingrid N. Visser; Jody S. Weir; Alastair G. Judkins; Tom Brough; Marta Guerra; Lily Kozmian‐Ledward; Karen A. Stockin
Two ecotypes of the common bottlenose dolphin (Tursiops truncatus) occur in New Zealand waters: a widely studied Nationally Endangered coastal ecotype and a little‐known oceanic ecotype. Site fidelity and association patterns of the oceanic ecotype, and home range overlap with the coastal ecotype, are examined from photo‐identification records collected off northeastern New Zealand between 2005 and
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Passive acoustic monitoring of the distribution patterns of Irrawaddy dolphins (Orcaella brevirostris) in the middle reaches of the Ayeyarwady River, Myanmar Mar. Mamm. Sci. (IF 1.651) Pub Date : 2020-07-04 Zhi‐Tao Wang; Peng‐Xiang Duan; Tomonari Akamatsu; Ke‐Xiong Wang; Ding Wang
The Irrawaddy dolphins (Orcaella brevirostris) are an endangered species. Thus, up‐to‐date information on the distribution pattern of dolphins is critical for its proper management and conservation. Using a towed passive acoustic monitoring device, the distribution pattern of the Irrawaddy dolphins in the middle reaches of the Ayeyarwady River, Myanmar, was investigated during a vessel‐based survey
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Social behavior increases in multipod aggregations of southern Alaska resident killer whales (Orcinus orca) Mar. Mamm. Sci. (IF 1.651) Pub Date : 2020-07-04 Daniel W. Olsen; Craig O. Matkin; Franz J. Mueter; Shannon Atkinson
Killer whales (Orcinus orca) are highly social and occasionally gather in large aggregations that reach 150 individuals. During 338 encounters with Southern Alaska resident killer whales, we collected 1,352 hr of behavioral data to assess the probability of various behaviors based on season, number of pods present, presence of rarely sighted pods, and number of mitochondrial DNA haplotypes present
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Maternal behaviors of gray whales (Eschrichtius robustus) on a summer foraging site Mar. Mamm. Sci. (IF 1.651) Pub Date : 2020-07-02 Rianna E. Burnham; David A. Duffus
The weaning period for gray whale (Eschrichtius robustus) calves is important for maternal instruction and learning. We examined observational and acoustic data from a foraging site for evidence of calf development and mother‐young information transfer. Site survey data demonstrated an initial prioritization of calf protection by using shallow shoreline areas. Foraging in more open water was only noted
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Factors influencing dolphin depredation in coastal fisheries of the northern Aegean Sea: Implications on defining mitigation measures Mar. Mamm. Sci. (IF 1.651) Pub Date : 2020-06-15 Androniki Pardalou; Athanassios C. Tsikliras
Dolphin interactions with coastal fisheries are of major concern, reportedly leading to gear damage, which increases the cost of coastal fishing globally and in the Mediterranean Sea. The aim of this study was to determine the effect that gear, target species, mesh size, depth, soaking duration, fishing area, and season have on net depredation frequency and to offer insights on possible mitigation
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Respiration cycle duration and seawater flux through open blowholes of humpback (Megaptera novaeangliae) and North Atlantic right (Eubalaena glacialis) whales Mar. Mamm. Sci. (IF 1.651) Pub Date : 2020-05-29 Maria Clara Iruzun Martins; Carolyn Miller; Phillip Hamilton; Jooke Robbins; Daniel P. Zitterbart; Michael Moore
Little is known about the dynamics of baleen whale respiratory cycles, especially the mechanics and activity of the blowholes and their interaction with seawater. In this study, the duration of complete respiration cycles (expiration/inhalation events) were quantified for the first time in two species: North Atlantic right whale (NARW) and humpback whale (HW) using high resolution, detailed imagery
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Southern right whales show no behavioral response to low noise levels from a nearby unmanned aerial vehicle Mar. Mamm. Sci. (IF 1.651) Pub Date : 2020-05-13 Fredrik Christiansen, Mia L. K. Nielsen, Claire Charlton, Lars Bejder, Peter T. Madsen
Unmanned aerial vehicles (UAVs) are increasingly used for wildlife research and monitoring, but little information exists on their potential effect on marine mammals. We assessed the effects of a UAV on the behavior of southern right whales (Eubalaena australis) in Australia. Focal follows of ten right whale mother‐calf pairs were conducted using a theodolite. Control data were recorded for 30 min
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Gray whales hear and respond to signals from a 21–25 kHz active sonar Mar. Mamm. Sci. (IF 1.651) Pub Date : 2020-05-10 Adam S. Frankel; Peter J. Stein
Shore‐based theodolite tracking of eastern gray whale (Eschrichtius robustus) movements was conducted to test for potential whale responses to a high‐frequency sonar system. Southbound migrating whales were observed from two California shore observation stations as the whales swam past the source vessel that was moored in their migration path. The sonar transducer was deployed from the vessel during
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Current population genetics of Japanese harbor seals: Two distinct populations found within a small area Mar. Mamm. Sci. (IF 1.651) Pub Date : 2020-05-05 Mariko Mizuno, Mari Kobayashi, Takeshi Sasaki, Takayuki Haneda, Takahito Masubuchi
We used microsatellite loci to understand the current population genetics of Japanese harbor seals, and found that they were subdivided into two distinct populations, one in Erimo and the other in eastern Hokkaido, despite being only 150 km apart and having no obvious geographical boundaries between them. Strong population subdivision between the two areas may be due to the small number of haul‐out
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Maximizing surveillance through spatial characterization of marine mammal stranding hot spots Mar. Mamm. Sci. (IF 1.651) Pub Date : 2020-05-05 Jennifer K. Olson; John Aschoff; Alice Goble; Shawn Larson; Joseph K. Gaydos
Spatial analyses of marine mammal stranding data can be used to identify stranding patterns and improve surveillance and monitoring. Using ArcGIS and SaTScan, we analyzed 12 years (2002–2014) of dead beachcast marine mammals from San Juan County, Washington, to better understand patterns of carcass deposition. We plotted the locations for 631 dead marine mammals and aggregated strandings into 1,000 m
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Mating patterns of dusky dolphins (Lagenorhynchus obscurus) explored using an unmanned aerial vehicle Mar. Mamm. Sci. (IF 1.651) Pub Date : 2020-04-29 Dara N. Orbach; Jordan Eaton; Lorenzo Fiori; Sarah Piwetz; Jody S. Weir; Melany Würsig; Bernd Würsig
Few studies have explored the mating patterns of free‐ranging cetaceans, largely because of logistical challenges. We used an unmanned aerial vehicle (UAV) to follow and video‐record 25 groups of mating dusky dolphins (Lagenorhynchus obscurus) near the surface of the water and examine how behavior patterns varied with mating group type. We collected aerial footage of dolphins mating in traditional
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Functional morphology of the taste buds of Florida manatee, Trichechus manatus latirostris Mar. Mamm. Sci. (IF 1.651) Pub Date : 2020-04-21 Meghan L. B. Barboza, Iskande V. Larkin
The Florida manatee, Trichechus manatus latirostris, is a fully aquatic, threatened marine mammal for which increased understanding of their physiology, reproduction, and nutrition supports management decisions. Manatees may use taste to distinguish saltwater gradients, toxin detection, food assessment, and social interactions. This study sought to locate and characterize manatee taste buds comparing
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