Abstract
The objective of this paper is to report on the demography and pathology of 131 Pacific walruses (Odobenus rosmarus divergens), primarily calves, found dead on the northwest coast of Alaska in September 2009. The walrus carcasses extended over approximately 120 km, but most were found where walruses had hauled out for several days on the beach at Icy Cape. The remote location and severe weather made access to the site difficult and limited the number and extent of necropsies. A total of 71 carcasses were examined: nine were necropsied, and 62 were classified externally for age, gender, blubber depth, and other parameters. The most likely causes of death were crushing trauma, particularly of the upper thorax, neck and head, or asphyxiation due to being trampled by larger animals.
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Acknowledgments
We acknowledge the following individuals: Anthony Fischbach, Dan Monson, Chad Jay, and Karen Oakley (U.S. Geological Survey, Alaska Science Center, Anchorage, AK); Joel Garlich-Miller, Jonathan Snyder, David Rippeto, and Eric Marek (U.S. Fish and Wildlife Service, AK); Jill Prewitt (Alaska SeaLife Center, Seward, AK); Craig George, Billy Adams, and the Bell 412 flight crew (North Slope Borough, Department of Wildlife Management and Search and Rescue, Barrow, AK); Harris Aguvluk (Wainwright, AK); Teri Rowles and the Working Group on Unusual Marine Mammal Mortality Events (National Oceanic and Atmospheric Administration) for their support of the response, both on and off site. Funding was provided by the National Oceanic and Atmospheric Administration, U.S. Fish and Wildlife Service, the Alaska SeaLife Center, and the North Slope Borough. We thank Glenn Olson, Doug Burn, Karen Wolf, and anonymous peers for reviewing the manuscript. Mention of trade names is for descriptive purposes only and does not constitute endorsement by the federal government.
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Goertz, C.E.C., Polasek, L., Burek, K. et al. Demography and pathology of a pacific walrus (Odobenus rosmarus divergens) mass-mortality event at Icy Cape, Alaska, September 2009. Polar Biol 40, 989–996 (2017). https://doi.org/10.1007/s00300-016-2023-x
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DOI: https://doi.org/10.1007/s00300-016-2023-x