Funding include Washington Department of Fish and Wildlife under NOAA Permit #18786-03, Cascadia Research Collective, Portland State University, NOAA/NMFS, Oregon State University's Marine Mammal Institute, the Oregon Veterinary Diagnostic Laboratory, Jonathan Scordino and Adrianne Akmaijan of the Makah Fisheries marine mammal research unit for response to cases in Neah Bay area, and Progressive Animal Welfare Society (PAWS), Lynnwood WA.
Marine Mammal Science
Guadalupe fur seals (GFS) -- Identification, Marine mammals -- Identification
Guadalupe fur seals (GFS), Arctocephalus philippii townsendi, an U.S. Endangered Species Act threatened pinniped, have recently reappeared in their historic range along the western seaboard of the continental United States. Starting 2005 through 2016, 169 GFSs stranded in Washington and Oregon, involving two designated unusual mortality events. The circumstances surrounding GFS strandings, mortality, and their increased presence in Oregon and Washington were analyzed during this study. Detailed necropsies, histopathology (n = 93), and epidemiological analysis found three main causes of death (COD): emaciation (44%), trauma (29%), and infectious disease (19%) and the factors associated with overall strandings and emaciation. Trauma included many cases found associated with fisheries interactions and clustered near the mouth of the Columbia River, where high levels of commercial fishing occur. The most common pathogens found associated with disease were Toxoplasma gondii, Sarcocystis neurona, and gastrointestinal helminths. Seasonality and upwelling were associated with higher stranding numbers regardless of COD. Seasonal migration into the region, coinciding with postweaning, suggests young GFSs are in search of prey and habitat resources. Reemergence of GFSs is likely due to conservation efforts, which have been critical for species recovery in the region. Continued monitoring is needed as this vulnerable species continues to rebound.
© 2020 Society for Marine Mammalogy.
Locate the Document
D'Agnese, E., Lambourn, D., Rice, J., Duffield, D., Huggins, J., Spraker, T., ... & Jeffries, S. (2020). Reemergence of Guadalupe fur seals in the US Pacific Northwest: The epidemiology of stranding events during 2005–2016. Marine Mammal Science.