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https://www.readbyqxmd.com/read/27878087/collateral-damage-to-marine-and-terrestrial-ecosystems-from-yankee-whaling-in-the-19th-century
#1
Joshua Drew, Elora H López, Lucy Gill, Mallory McKeon, Nathan Miller, Madeline Steinberg, Christa Shen, Loren McClenachan
Yankee whalers of the 19th century had major impacts on populations of large whales, but these leviathans were not the only taxa targeted. Here, we describe the "collateral damage," the opportunistic or targeted taking of nongreat whale species by the American whaling industry. Using data from 5,064 records from 79 whaling logs occurring between 1840 and 1901, we show that Yankee whalers captured 5,255 animals across three large ocean basins from 32 different taxonomic categories, including a wide range of marine and terrestrial species...
November 2016: Ecology and Evolution
https://www.readbyqxmd.com/read/27824339/dna-evidence-of-bowhead-whale-exploitation-by-greenlandic-paleo-inuit-4-000-years-ago
#2
Frederik Valeur Seersholm, Mikkel Winther Pedersen, Martin Jensen Søe, Hussein Shokry, Sarah Siu Tze Mak, Anthony Ruter, Maanasa Raghavan, William Fitzhugh, Kurt H Kjær, Eske Willerslev, Morten Meldgaard, Christian M O Kapel, Anders Johannes Hansen
The demographic history of Greenland is characterized by recurrent migrations and extinctions since the first humans arrived 4,500 years ago. Our current understanding of these extinct cultures relies primarily on preserved fossils found in their archaeological deposits, which hold valuable information on past subsistence practices. However, some exploited taxa, though economically important, comprise only a small fraction of these sub-fossil assemblages. Here we reconstruct a comprehensive record of past subsistence economies in Greenland by sequencing ancient DNA from four well-described midden deposits...
November 8, 2016: Nature Communications
https://www.readbyqxmd.com/read/27547372/dietary-habits-of-polar-bears-in-foxe-basin-canada-possible-evidence-of-a-trophic-regime-shift-mediated-by-a-new-top-predator
#3
Melissa P Galicia, Gregory W Thiemann, Markus G Dyck, Steven H Ferguson, Jeff W Higdon
Polar bear (Ursus maritimus) subpopulations in several areas with seasonal sea ice regimes have shown declines in body condition, reproductive rates, or abundance as a result of declining sea ice habitat. In the Foxe Basin region of Nunavut, Canada, the size of the polar bear subpopulation has remained largely stable over the past 20 years, despite concurrent declines in sea ice habitat. We used fatty acid analysis to examine polar bear feeding habits in Foxe Basin and thus potentially identify ecological factors contributing to population stability...
August 2016: Ecology and Evolution
https://www.readbyqxmd.com/read/27530539/dental-and-temporomandibular-joint-pathology-of-the-walrus-odobenus-rosmarus
#4
J N Winer, B Arzi, D M Leale, P H Kass, F J M Verstraete
Maxillae and/or mandibles from 76 walruses (Odobenus rosmarus) were examined macroscopically according to predefined criteria. The museum specimens were acquired between 1932 and 2014. Forty-five specimens (59.2%) were from male animals, 29 (38.2%) from female animals and two (2.6%) from animals of unknown sex, with 58 adults (76.3%) and 18 young adults (23.7%) included in this study. The number of teeth available for examination was 830 (33.6%); 18.5% of teeth were absent artefactually, 3.3% were deemed to be absent due to acquired tooth loss and 44...
August 2016: Journal of Comparative Pathology
https://www.readbyqxmd.com/read/27142598/enamel-ultrastructure-of-fossil-and-modern-pinnipeds-evaluating-hypotheses-of-feeding-adaptations-in-the-extinct-walrus-pelagiarctos
#5
Carolina Loch, Robert W Boessenecker, Morgan Churchill, Jules Kieser
This study aimed to assess the enamel ultrastructure in modern otariid pinnipeds and in the extinct walrus Pelagiarctos. Teeth of the New Zealand fur seal (Arctocephalus forsteri), sea lion (Phocarctos hookeri), and fossil walrus Pelagiarctos thomasi were embedded, sectioned, etched, and analyzed via scanning electron microscopy. The enamel of NZ otariids and Pelagiarctos was prismatic and moderately thick, measuring 150-450 μm on average. It consisted of transversely oriented Hunter-Schreger bands (HSBs) from the enamel-dentine junction (EDJ) to near the outer surface, where it faded into prismless enamel less than 10 μm thick...
June 2016: Die Naturwissenschaften
https://www.readbyqxmd.com/read/27082720/sex-specific-energetics-of-pacific-walruses-odobenus-rosmarus-divergens-during-the-nursing-interval
#6
Shawn R Noren, Mark S Udevitz, Chadwick V Jay
Habitat use and activity patterns of Pacific walruses (Odobenus rosmarus divergens) have changed with climate-induced reductions in sea ice. Increases in the time active in water could result in negative energy balance, precluding females from sustaining lactation, which could impact population demographics. Little is known about lactation costs in walruses. We examined the energetics of 0-2-yr-old walrus calves by using Bayesian hierarchical models based on longitudinal husbandry records of growth (n = 6 females and 7 males) and caloric intake (n = 5 females and 6 males) as a proxy for maternal lactation costs...
March 2016: Physiological and Biochemical Zoology: PBZ
https://www.readbyqxmd.com/read/27054472/pulmonary-mast-cell-tumor-and-possible-paraganglioma-in-a-free-ranging-pacific-walrus-odobenus-rosmarus-divergens-barrow-alaska-usa
#7
Mauricio Seguel, Raphaela Stimmelmayr, Elizabeth Howerth, Nicole Gottdenker
We describe a pulmonary mast cell tumor in a subsistence-harvested free-ranging Pacific walrus (Odobenus rosmarus divergens). Neoplastic cells effacing a focal area of pulmonary parenchyma were characterized by rare metachromatic granules and positive staining for C-kit. We also report co-occurrence of a peribronchial mass with a morphologic and immunohistochemical profile compatible with paraganglioma.
April 28, 2016: Journal of Wildlife Diseases
https://www.readbyqxmd.com/read/27049757/towards-a-better-understanding-of-the-effects-of-uv-on-atlantic-walruses-odobenus-rosmarus-rosmarus-a-study-combining-histological-data-with-local-ecological-knowledge
#8
Laura M Martinez-Levasseur, Chris M Furgal, Mike O Hammill, Gary Burness
Walruses, Odobenus rosmarus, play a key role in the Arctic ecosystem, including northern Indigenous communities, which are reliant upon walruses for aspects of their diet and culture. However, walruses face varied environmental threats including rising sea-water temperatures and decreasing ice cover. An underappreciated threat may be the large amount of solar ultraviolet radiation (UV) that continues to reach the Arctic as a result of ozone loss. UV has been shown to negatively affect whales. Like whales, walrus skin is unprotected by fur, but in contrast, walruses spend long periods of time hauled-out on land...
2016: PloS One
https://www.readbyqxmd.com/read/27039507/decadal-bering-sea-seascape-change-consequences-for-pacific-walruses-and-indigenous-hunters
#9
G Carleton Ray, Gary L Hufford, James E Overland, Igor Krupnik, Jerry McCormick-Ray, Karen Frey, Elizabeth Labunski
The most significant factors currently affecting the Pacific walrus (Odobenus rosmarus divergens) population are climate change and consequent changes in sea-ice morphology and dynamics. This paper integrates recent physical sea-ice change in the Bering Sea with biological and ecological conditions of walruses in their winter-spring reproductive habitat. Historically, walrus in winter-spring depended on a critical mass of sea-ice habitat to optimize social networking, reproductive fitness, feeding behavior, migration, and energetic efficiency...
January 2016: Ecological Applications: a Publication of the Ecological Society of America
https://www.readbyqxmd.com/read/27010907/zinc-isotope-ratios-as-indicators-of-diet-and-trophic-level-in-arctic-marine-mammals
#10
Klervia Jaouen, Paul Szpak, Michael P Richards
Carbon and nitrogen stable isotope ratios of bone collagen are an established method for dietary reconstruction, but this method is limited by the protein preservation. Zinc (Zn) is found in bioapatite and the isotopic compositions of this element constitute a very promising dietary indicator. The extent of fractionation of Zn isotopes in marine environments, however, remains unknown. We report here on the measurement of zinc, carbon and nitrogen isotopes in 47 marine mammals from the archaeological site of Arvik in the Canadian Arctic...
2016: PloS One
https://www.readbyqxmd.com/read/26986498/effect-of-climate-change-on-runoff-of-campylobacter-and-cryptosporidium-from-land-to-surface-water
#11
Ankie Sterk, Jack Schijven, Ana Maria de Roda Husman, Ton de Nijs
Faeces originating from wildlife, domestic animals or manure-fertilized fields, is considered an important source of zoonotic pathogens to which people may be exposed by, for instance, bathing or drinking-water consumption. An increase in runoff, and associated wash-off of animal faeces from fields, is assumed to contribute to the increase of disease outbreaks during periods of high precipitation. Climate change is expected to increase winter precipitation and extreme precipitation events during summer, but has simultaneously also other effects such as temperature rise and changes in evapotranspiration...
May 15, 2016: Water Research
https://www.readbyqxmd.com/read/26892244/genetic-diversity-of-historical-atlantic-walruses-odobenus-rosmarus-rosmarus-from-bj%C3%A3-rn%C3%A3-ya-and-h%C3%A3-%C3%A3-ya-tusen%C3%A3-yane-svalbard-norway
#12
Charlotte Lindqvist, Tilottama Roy, Christian Lydersen, Kit M Kovacs, Jon Aars, Øystein Wiig, Lutz Bachmann
BACKGROUND: The population size of Atlantic walruses (Odobenus rosmarus rosmarus) is depleted relative to historical abundance levels. In Svalbard, centuries of over-exploitation brought the walrus herds to the verge of extinction, and such bottlenecks may have caused loss of genetic variation. To address this for Svalbard walruses, mitochondrial haplotypes of historical walruses from two major haul-out sites, Bjørnøya and Håøya, within the Archipelago were explored using bone samples from animals killed during the peak period of harvesting...
2016: BMC Research Notes
https://www.readbyqxmd.com/read/26878587/somatosensory-brainstem-thalamus-and-cortex-of-the-california-sea-lion-zalophus-californianus
#13
Eva K Sawyer, Emily C Turner, Jon H Kaas
Pinnipeds (sea lions, seals, and walruses) are notable for many reasons, including their ape-sized brains, their adaptation to a coastal niche that combines mastery of the sea with strong ties to land, and the remarkable abilities of their trigeminal whisker system. However, little is known about the central nervous system of pinnipeds. Here we report on the somatosensory areas of the nervous system of the California sea lion (Zalophus californianus). Using stains for Nissl, cytochrome oxidase, and vesicular glutamate transporters, we investigated the primary somatosensory areas in the brainstem, thalamus, and cortex in one sea lion pup and the external anatomy of the brain in a second pup...
June 15, 2016: Journal of Comparative Neurology
https://www.readbyqxmd.com/read/26821159/the-ancestral-carnivore-karyotype-as-substantiated-by-comparative-chromosome-painting-of-three-pinnipeds-the-walrus-the-steller-sea-lion-and-the-baikal-seal-pinnipedia-carnivora
#14
Violetta R Beklemisheva, Polina L Perelman, Natalya A Lemskaya, Anastasia I Kulemzina, Anastasia A Proskuryakova, Vladimir N Burkanov, Alexander S Graphodatsky
Karyotype evolution in Carnivora is thoroughly studied by classical and molecular cytogenetics and supplemented by reconstructions of Ancestral Carnivora Karyotype (ACK). However chromosome painting information from two pinniped families (Odobenidae and Otariidae) is noticeably missing. We report on the construction of the comparative chromosome map for species from each of the three pinniped families: the walrus (Odobenus rosmarus, Odobenidae-monotypic family), near threatened Steller sea lion (Eumetopias jubatus, Otariidae) and the endemic Baikal seal (Pusa sibirica, Phocidae) using combination of human, domestic dog and stone marten whole-chromosome painting probes...
2016: PloS One
https://www.readbyqxmd.com/read/26683564/a-draft-fur-seal-genome-provides-insights-into-factors-affecting-snp-validation-and-how-to-mitigate-them
#15
E Humble, A Martinez-Barrio, J Forcada, P N Trathan, M A S Thorne, M Hoffmann, J B W Wolf, J I Hoffman
Custom genotyping arrays provide a flexible and accurate means of genotyping single nucleotide polymorphisms (SNPs) in a large number of individuals of essentially any organism. However, validation rates, defined as the proportion of putative SNPs that are verified to be polymorphic in a population, are often very low. A number of potential causes of assay failure have been identified, but none have been explored systematically. In particular, as SNPs are often developed from transcriptomes, parameters relating to the genomic context are rarely taken into account...
July 2016: Molecular Ecology Resources
https://www.readbyqxmd.com/read/26651027/albicetus-oxymycterus-a-new-generic-name-and-redescription-of-a-basal-physeteroid-mammalia-cetacea-from-the-miocene-of-california-and-the-evolution-of-body-size-in-sperm-whales
#16
Alexandra T Boersma, Nicholas D Pyenson
Living sperm whales are represented by only three species (Physeter macrocephalus, Kogia breviceps and Kogia sima), but their fossil record provides evidence of an ecologically diverse array of different forms, including morphologies and body sizes without analog among living physeteroids. Here we provide a redescription of Ontocetus oxymycterus, a large but incomplete fossil sperm whale specimen from the middle Miocene Monterey Formation of California, described by Remington Kellogg in 1925. The type specimen consists of a partial rostrum, both mandibles, an isolated upper rostrum fragment, and incomplete tooth fragments...
2015: PloS One
https://www.readbyqxmd.com/read/26639991/a-colostrum-trypsin-inhibitor-gene-expressed-in-the-cape-fur-seal-mammary-gland-during-lactation
#17
Elizabeth A Pharo, Kylie N Cane, Julia McCoey, Ashley M Buckle, W H Oosthuizen, Christophe Guinet, John P Y Arnould
The colostrum trypsin inhibitor (CTI) gene and transcript were cloned from the Cape fur seal mammary gland and CTI identified by in silico analysis of the Pacific walrus and polar bear genomes (Order Carnivora), and in marine and terrestrial mammals of the Orders Cetartiodactyla (yak, whales, camel) and Perissodactyla (white rhinoceros). Unexpectedly, Weddell seal CTI was predicted to be a pseudogene. Cape fur seal CTI was expressed in the mammary gland of a pregnant multiparous seal, but not in a seal in its first pregnancy...
March 1, 2016: Gene
https://www.readbyqxmd.com/read/26347559/rapid-maturation-of-the-muscle-biochemistry-that-supports-diving-in-pacific-walruses-odobenus-rosmarus-divergens
#18
Shawn R Noren, Chadwick V Jay, Jennifer M Burns, Anthony S Fischbach
Physiological constraints dictate animals' ability to exploit habitats. For marine mammals, it is important to quantify physiological limits that influence diving and their ability to alter foraging behaviors. We characterized age-specific dive limits of walruses by measuring anaerobic (acid-buffering capacity) and aerobic (myoglobin content) capacities of the muscles that power hind (longissimus dorsi) and fore (supraspinatus) flipper propulsion. Mean buffering capacities were similar across muscles and age classes (a fetus, five neonatal calves, a 3 month old and 20 adults), ranging from 41...
October 2015: Journal of Experimental Biology
https://www.readbyqxmd.com/read/26338544/thermal-reference-points-as-an-index-for-monitoring-body-temperature-in-marine-mammals
#19
Mar Melero, Víctor Rodríguez-Prieto, Ana Rubio-García, Daniel García-Párraga, José Manuel Sánchez-Vizcaíno
BACKGROUND: Monitoring body temperature is essential in veterinary care as minor variations may indicate dysfunction. Rectal temperature is widely used as a proxy for body temperature, but measuring it requires special equipment, training or restraining, and it potentially stresses animals. Infrared thermography is an alternative that reduces handling stress, is safer for technicians and works well for untrained animals. This study analysed thermal reference points in five marine mammal species: bottlenose dolphin (Tursiops truncatus); beluga whale (Delphinapterus leucas); Patagonian sea lion (Otaria flavescens); harbour seal (Phoca vitulina); and Pacific walrus (Odobenus rosmarus divergens)...
2015: BMC Research Notes
https://www.readbyqxmd.com/read/26244784/a-new-late-miocene-odobenid-mammalia-carnivora-from-hokkaido-japan-suggests-rapid-diversification-of-basal-miocene-odobenids
#20
Yoshihiro Tanaka, Naoki Kohno
The modern walrus, Odobenus rosmarus, is specialized and only extant member of the family Odobenidae. They were much more diversified in the past, and at least 16 genera and 20 species of fossil walruses have been known. Although their diversity increased in the late Miocene and Pliocene (around 8-2 Million years ago), older records are poorly known. A new genus and species of archaic odobenid, Archaeodobenus akamatsui, gen. et sp. nov. from the late Miocene (ca. 10.0-9.5 Ma) top of the Ichibangawa Formation, Hokkaido, northern Japan, suggests rapid diversification of basal Miocene walruses...
2015: PloS One
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