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Marine megafauna species are affected by a wide range of anthropogenic threats. To evaluate the risk of such threats, species’ vulnerability to each threat must first be determined. We build on the existing threats classification scheme and ranking system of the International Union for Conservation of Nature (IUCN) Red List of Threatened Species by assessing the vulnerability of 256 marine megafauna species to 23 at‐sea threat...
Harbor seal ( Phoca vitulina ) numbers in the United States rebounded after the implementation of conservation measures associated with the Marine Mammal Protection Act of 1972 (MMPA). Stock estimates are a critical tool for assessing species status and management options under the MMPA and for modeling efforts designed to evaluate the role of pinnipeds in marine ecosystems. We conducted aerial surveys of harbor seal haul‐out...
Prolonging survival in good health is a fundamental societal goal. However, the leading determinants of disability-free survival in healthy older people have not been well established. Data from ASPREE, a bi-national placebo-controlled trial of aspirin with 4.7 years median follow-up, was analysed. At enrolment, participants were healthy and without prior cardiovascular events, dementia or persistent physical disability. Disab...
Studying patterns in marine mammal stranding cases can provide insight into changes in population health, abundance, and distribution. Cetaceans along the United States West coast strand for a wide variety of reasons, including disease, injury, and poor nutritional status, all of which may be caused by both natural and anthropogenic factors. Examining the potential drivers of these stranding cases can reveal how populations re...
Calculation of Hydroacoustic Propagation and Conversion to Seismic Phases at T-StationsNARA Subscribed
The International Monitoring System (IMS) hydroacoustic network consists of six hydrophone stations and 5 T-stations. The IMS T-stations are high-frequency seismic stations (sample rates of 100 Hz) situated on islands or coastal stations and intended primarily to capture impulsive signals from in-water explosions. However, while there are numerous recordings of impulsive-like signals from in-water explosions at the hydrophone...
Reemergence of Guadalupe fur seals in the U.S. Pacific Northwest: The epidemiology of stranding events during 2005–2016NARA Subscribed
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 prese...
Blood sampling through the caudal vasculature is a widely used technique in fish biology for investigating organismal health and physiology. In live fishes, it can provide a quick, easy and relatively non‐invasive method for obtaining a blood sample ( cf . cannulation and cardiac puncture). Here, a general set of recommendations are provided for optimizing the blood sampling protocol that reflects best practices in animal welf...
Habitat characteristics are primary determinants of nearshore marine communities. However, biological drivers like predation can also be important for community composition. Sea otters ( Enhydra lutris ssp.) are a salient example of a keystone species exerting top‐down control on ecosystem community structure. The translocation and subsequent population growth and range expansion of the northern sea otter ( Enhydra lutris keny...
Postrelease movement of rehabilitated harbor seal ( Phoca vitulina richardii ) pups compared with cohort‐matched wild seal pupsNARA Subscribed
Harbor seal ( Phoca vitulina richardii ) populations in the inland waters of Washington and British Columbia are at or near carrying capacity. Stranded pups often are collected and admitted to rehabilitation centers, and then released when they reach a weight of 22 kg and meet a variety of preestablished health and release conditions. While rehabilitation is common practice, it is unclear if rehabilitated seal pups behave like...
Growth and Development in Free‐ranging Harbor Seal ( Phoca Vitulina ) Pups from Southern British Columbia, CanadaNARA Subscribed
A bstract Harbor seals ( Phoca vitulina ) are small pinnipeds that are widely distributed throughout the temperate coastal regions of the Atlantic and Pacific oceans. We determined birth mass, neonatal growth rates, weaning age, and weaning mass of NE Pacific harbor seals ( P. v. richardsi ) during a capture‐recapture study that spanned the nursing period (Sidney Island, British Columbia, Canada). Of 46 harbor seal pups initia...
Correcting Aerial Survey Counts of Harbor Seals ( Phoca Vitulina Richardsi ) in Washington and OregonNARA Subscribed
A bstract Aerial surveys of harbor seals on land produce only a minimum assessment of the population; a correction factor to account for the missing animals is necessary to estimate total abundance. In 1991 and 1992, VHF radio tags were deployed on harbor seals ( n = 124) at six sites in Washington and Oregon. During aerial surveys a correction factor to account for seals in the water was determined from the proportion of radi...
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