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Ivan D. Fedutin - One of the best experts on this subject based on the ideXlab platform.
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records of a new cetacean species of the genus Berardius from russian waters
Russian Journal of Marine Biology, 2020Co-Authors: Ivan D. Fedutin, Alexander M. Burdin, Ilya G Meschersky, Olga Filatova, O V Titova, I G Bobyr, Erich HoytAbstract:Until recently, it has been believed that only one cetacean species of the genus Berardius, the Baird’s beaked whale (Berardius bairdii Stejneger, 1883), inhabits the northern Pacific Ocean. However, a genetic analysis of tissue samples and morphometric data provide convincing evidence for the existence of a previously undescribed Berardius species sympatric to Baird’s beaked whale, which is referred to as “black” beaked whale. The high probability of occurrence of the black beaked whale in Russian waters is established and its possible range is described in the present study. A genetic analysis of the mitochondrial DNA control region was carried out for 28 new specimens of the genus Berardius from four Far Eastern regions. According to the results, all specimens from the Commander Islands and Kamchatka Gulf belonged to the phylogroup of the Baird’s beaked whale. Of the two dead animals stranded on the Kunashir Island coast, one was identified as Baird’s beaked whale and the other as black beaked whale. Another two black beaked whales were found on the eastern coast of Sakhalin Island. These are the first records of the new Berardius species from the Russian territory confirmed by genetic analysis.
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Genetic structure of the beaked whale genus Berardius in the North Pacific, with genetic evidence for a new species
Marine Mammal Science, 2016Co-Authors: Phillip A. Morin, Merel L. Dalebout, Scott C. Baker, Reid S. Brewer, Alexander M. Burdin, Ivan D. Fedutin, Olga A. Filatova, Erich Hoyt, Jean Luc Jung, Morgane LaufAbstract:There are two recognized species in the genus Berardius, Baird’s and Arnoux’s beaked whales. In Japan, whalers have traditionally recognized two forms of Baird’s beaked whales, the common “slate-gray” form and a smaller, rare “black” form. Previous comparison of mtDNA control region sequences from three black specimens to gray specimens around Japan indicated that the two forms comprise different stocks and potentially different species. We have expanded sampling to include control region haplotypes of 178 Baird’s beaked whales from across their range in the North Pacific. We identified five additional specimens of the black form from the Aleutian Islands and Bering Sea, for a total of eight “black” specimens. The divergence between mtDNA haplotypes of the black and gray forms of Baird’s beaked whale was greater than their divergence from the congeneric Arnoux’s beaked whale found in the Southern Ocean, and similar to that observed among other congeneric beaked whale species. Taken together, genetic evidence from specimens in Japan and across the North Pacific, combined with evidence of smaller adult body size, indicate presence of an unnamed species of Berardius in the North Pacific.
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occurrence and social structure of baird s beaked whales Berardius bairdii in the commander islands russia
Marine Mammal Science, 2015Co-Authors: Ivan D. Fedutin, Olga Filatova, Evgeny G Mamaev, Alexandr M Burdin, Erich HoytAbstract:The social structure of Baird's beaked whales is completely unstudied, and it is unknown if either females or males form long-term social associations or occur in stable groups. In this paper we summarize our observations of individually identified animals over the span of 6 yr to provide insight on their long-term social structure. We have identified 122 whales, with 28 of them encountered three times or more and thus included in the analysis of social structure. We found that the whales exhibited nonrandom patterns of social associations with some individuals preferentially associating with each other. Whales with more scarred skin had higher maximum association coefficients, which indicates that older animals and/or males were more inclined to form stable associations. Cluster analysis with a modularity test for gregariousness divided the whales into four clusters. Whales from the same clusters did not always occur together, but some individuals retained stable associations over several years. The strength of social relationships decayed over periods of months, with between-year relationships showing little deviation from what would be expected if association was random. Generally these findings do not correspond to a stable society with fixed groups but instead suggest a fission-fusion society with some stable alliances.
Naoki Kohno - One of the best experts on this subject based on the ideXlab platform.
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the oldest fossil record of the extant genus Berardius odontoceti ziphiidae from the middle to late miocene boundary of the western north pacific
Royal Society Open Science, 2021Co-Authors: Ayako Kawatani, Naoki KohnoAbstract:A new species of a beaked whale that belongs to the extant genus Berardius is described from the Middle to Late Miocene boundary age Tsurushi Formation (ca 12.3–11.5 Ma) on the Sado Island, Niigata...
Toshiya Kishiro - One of the best experts on this subject based on the ideXlab platform.
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abundance estimation of long diving animals using line transect methods
Biometrics, 2012Co-Authors: Hiroshi Okamura, Shingo Minamikawa, Hans J Skaug, Toshiya KishiroAbstract:Line transect sampling is one of the most widely used methods for estimating the size of wild animal populations. An assumption in standard line transect sampling is that all the animals on the trackline are detected without fail. This assumption tends to be violated for marine mammals with surfacing/diving behaviors. The detection probability on the trackline is estimated using duplicate sightings from doubleâplatform line transect methods. The doubleâplatform methods, however, are insufficient to estimate the abundance of longâdiving animals because these animals can be completely missed while the observers pass. We developed a more flexible hazard probability model that incorporates information on surfacing/diving patterns obtained from telemetry data. The model is based on a stochastic point process and is statistically tractable. A simulation study showed that the new model provides nearâunbiased abundance estimates, whereas the traditional hazard rate and hazard probability models produce considerably biased estimates. As an illustration, we applied the model to data on the Bairdâs beaked whale (Berardius bairdii) in the western North Pacific.
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localization of aquaporin 2 renal morphology and urine composition in the bottlenose dolphin and the baird s beaked whale
Journal of Comparative Physiology B-biochemical Systemic and Environmental Physiology, 2008Co-Authors: Miwa Suzuki, Toshiya Kishiro, Naoko Endo, Yuichi Nakano, Haruhiko Kato, Kiyoshi AsahinaAbstract:This study examined the distribution pattern of aquaporin-2 (AQP2), relative medullary thickness (RMT) and urine properties in the bottlenose dolphin Tursiops truncatus and Baird’s beaked whale Berardius bairdii. Immunohistochemical studies revealed that AQP2 was localized in the collecting tubules/ducts of both species’ renicules, as in terrestrial mammals. The collecting ducts with AQP2 were thinner and arranged more densely in the dolphin than in the whale. RMT values in the renicule were moderate in both species, but were significantly higher in the dolphin (6.0 ± 0.9) than the whale (4.9 ± 0.7). Urine of the bottlenose dolphin is comparatively concentrated (osmolality: 1715.7 ± 279.4 mOsm kg−1, Na+: 490.1 ± 87.9 mmol l−1, Cl−: 402.7 ± 79.6 mmol l−1, K+: 80.7 ± 25.8 mmol l−1, urea nitrogen: 703.5 ± 253.9 mmol l−1), while urine of the dead Baird’s beaked whale is less concentrated (osmolality: 837.5 ± 293.8 mOsm kg−1, Na+: 192.9 ± 81.5 mmol l−1, Cl−: 159.9 ± 71.4 mmol l−1, K+: 44.3 ± 29.5 mmol l−1, urea nitrogen: 270.7 ± 120.3 mmol l−1). These data suggest it is possible that the differences in these renal morphological features may be related in some way to the difference in urine composition between the species, although further studies are necessary.
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diving behaviour of a baird s beaked whale Berardius bairdii in the slope water region of the western north pacific first dive records using a data logger
Fisheries Oceanography, 2007Co-Authors: Shingo Minamikawa, Toshihide Iwasaki, Toshiya KishiroAbstract:A depth and temperature data logger was deployed by air gun on an individual Baird’s beaked whale (Berardius bairdii) off the Pacific coast of Japan. The retrieved data logger recorded 81 dives over approximately 29 h. The maximum recorded depth and the longest dive duration were 1777 m and 64.4 min, respectively. All dives were classified into three categories by depth: deep dives (>1000 m), intermediate dives (100–1000 m), and shallow dives (<100 m). Several intermediate dives generally followed a deep dive, and sequential shallow dives followed several intermediate dives in the record of the Baird’s beaked whale.
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feeding habits of baird s beaked whale Berardius bairdii in the western north pacific and sea of okhotsk off japan
Fisheries Science, 2003Co-Authors: Hiroshi Ohizumi, Toshiya Kishiro, Tatsuya Isoda, Hidehiro KatoAbstract:: We examined the stomach contents of 26 Baird's beaked whales caught off the coast of Japan by small-type coastal whalers. The main prey for these whales was rat-tails and hakes in the western North Pacific. Pollock and squids were also important food in the whales collected from the southern Sea of Okhotsk. The prey species found in the stomachs of the whales were almost identical to those caught in bottom-trawl nets at depths greater than about 1000 m in the western North Pacific, which suggests that the Baird's beaked whale forages for prey at depths of about 1000 m or more. Baird's beaked whales in the western North Pacific migrate to waters of 1000–3000 m in depth, where demersal fish are abundant. This implies that Baird's beaked whales migrate to waters where demersal fish, especially rat-tails and hakes, are abundant. Although there is limited information on the feeding habits of ziphiid whales, they are generally thought to prefer squid. The present data suggest that demersal fish are also important prey for ziphiid whales.
Erich Hoyt - One of the best experts on this subject based on the ideXlab platform.
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records of a new cetacean species of the genus Berardius from russian waters
Russian Journal of Marine Biology, 2020Co-Authors: Ivan D. Fedutin, Alexander M. Burdin, Ilya G Meschersky, Olga Filatova, O V Titova, I G Bobyr, Erich HoytAbstract:Until recently, it has been believed that only one cetacean species of the genus Berardius, the Baird’s beaked whale (Berardius bairdii Stejneger, 1883), inhabits the northern Pacific Ocean. However, a genetic analysis of tissue samples and morphometric data provide convincing evidence for the existence of a previously undescribed Berardius species sympatric to Baird’s beaked whale, which is referred to as “black” beaked whale. The high probability of occurrence of the black beaked whale in Russian waters is established and its possible range is described in the present study. A genetic analysis of the mitochondrial DNA control region was carried out for 28 new specimens of the genus Berardius from four Far Eastern regions. According to the results, all specimens from the Commander Islands and Kamchatka Gulf belonged to the phylogroup of the Baird’s beaked whale. Of the two dead animals stranded on the Kunashir Island coast, one was identified as Baird’s beaked whale and the other as black beaked whale. Another two black beaked whales were found on the eastern coast of Sakhalin Island. These are the first records of the new Berardius species from the Russian territory confirmed by genetic analysis.
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Genetic structure of the beaked whale genus Berardius in the North Pacific, with genetic evidence for a new species
Marine Mammal Science, 2016Co-Authors: Phillip A. Morin, Merel L. Dalebout, Scott C. Baker, Reid S. Brewer, Alexander M. Burdin, Ivan D. Fedutin, Olga A. Filatova, Erich Hoyt, Jean Luc Jung, Morgane LaufAbstract:There are two recognized species in the genus Berardius, Baird’s and Arnoux’s beaked whales. In Japan, whalers have traditionally recognized two forms of Baird’s beaked whales, the common “slate-gray” form and a smaller, rare “black” form. Previous comparison of mtDNA control region sequences from three black specimens to gray specimens around Japan indicated that the two forms comprise different stocks and potentially different species. We have expanded sampling to include control region haplotypes of 178 Baird’s beaked whales from across their range in the North Pacific. We identified five additional specimens of the black form from the Aleutian Islands and Bering Sea, for a total of eight “black” specimens. The divergence between mtDNA haplotypes of the black and gray forms of Baird’s beaked whale was greater than their divergence from the congeneric Arnoux’s beaked whale found in the Southern Ocean, and similar to that observed among other congeneric beaked whale species. Taken together, genetic evidence from specimens in Japan and across the North Pacific, combined with evidence of smaller adult body size, indicate presence of an unnamed species of Berardius in the North Pacific.
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occurrence and social structure of baird s beaked whales Berardius bairdii in the commander islands russia
Marine Mammal Science, 2015Co-Authors: Ivan D. Fedutin, Olga Filatova, Evgeny G Mamaev, Alexandr M Burdin, Erich HoytAbstract:The social structure of Baird's beaked whales is completely unstudied, and it is unknown if either females or males form long-term social associations or occur in stable groups. In this paper we summarize our observations of individually identified animals over the span of 6 yr to provide insight on their long-term social structure. We have identified 122 whales, with 28 of them encountered three times or more and thus included in the analysis of social structure. We found that the whales exhibited nonrandom patterns of social associations with some individuals preferentially associating with each other. Whales with more scarred skin had higher maximum association coefficients, which indicates that older animals and/or males were more inclined to form stable associations. Cluster analysis with a modularity test for gregariousness divided the whales into four clusters. Whales from the same clusters did not always occur together, but some individuals retained stable associations over several years. The strength of social relationships decayed over periods of months, with between-year relationships showing little deviation from what would be expected if association was random. Generally these findings do not correspond to a stable society with fixed groups but instead suggest a fission-fusion society with some stable alliances.
Robert L Brownell - One of the best experts on this subject based on the ideXlab platform.
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mass stranding of baird s beaked whales at san jose island gulf of california mexico
Latin American Journal of Aquatic Mammals, 2007Co-Authors: Gustavo Cardenashinojosa, U Gonzalezperal, W Del Toroorozco, Robert L BrownellAbstract:The Baird's or giant beaked whale ( Berardius bairdii ) is endemic to the North Pacific Ocean. In the eastern North Pacific, seasonal movements are poorly understood. Historic California catches suggest two peaks of abundance, in July and October. Mass strandings of Baird's beaked whales are rare. Prior to this report only two records were known, in the Bay of La Paz, Mexico in 1986 and Sagami Bay, Japan, in 1987; both mass strandings included male and females. Here we report a mass stranding of 10 Baird's beaked whales at San Jose lsland in the Gulf of California on 31 July 2006. The group was composed only by males ranging from 9.97m to 11.05m. The estimated age, based on the dental group layers, ranged from 9 to 42 years. The cause of this stranding is unknown, although with the large number of squid also found dead in the area, it is possible that the whales could have been following the squid, one of their main prey. The mass stranding of 10 mature males reported here supports the idea of a seasonal presence, during summer, of this species in the waters of the southwest Gulf of California. The group composition supports a reproductive strategy where the old males have a major role in the guidance and protection of inexperienced weaned and young males, unlike sperm whale bachelor groups, where all males are typically the same age.
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diets of baird s beaked whales Berardius bairdii in the southern sea of okhotsk and off the pacific coast of honshu japan
Marine Mammal Science, 2002Co-Authors: William A Walker, James G. Mead, Robert L BrownellAbstract:Stomach contents were analyzed from 127 Baird’s beaked whales, Berardizls bdirdii, taken in coastal waters of Japan. During late July-August of 19851987, 1989, and 1991, 107 samples were collected from off the Pacific coast of Honshu. An additional 20 samples were collected from whales taken in the southern Sea of Okhotsk during late August-September of 1988 and 1989. Prey identification using fish otoliths and cephalopod beaks revealed the whales fed primarily on deep-water gadiform fishes and cephalopods in both regions. Prey species diversity and the percentage of cephalopods and fish differed between the two regions. Off the Pacific coast of Honshu the whales fed primarily on benthopelagic fishes (81.8%) and only 18.0% on cephalopods. Eight species of fish representing two families, the codlings (Moridae) and the grenadiers (Macrouridde), collectively made up 81.3% of the total. Thirty species of cephalopods representing 14 families made up 12.7%. In the southern Sea of Okhotsk, cephalopods accounted for 87.1% of stomach contents. The families Gonatidae and Cranchiidae were the predominant cephalopod prey, accounting for 86.7% of the diet. Gadiform fish accounted for only 12.9% of the diet. Longfin codling, Laernonma longipes, was the dominant fish prey in both regions. Depth distribution of the two commonly consumed fish off the Pacific coast of