Eumetopias jubatus (Steller sea lions) that breed on the Oregon coast are generally smaller than those found in Alaska. During the breeding season, male Zalophus californianus (California sea lions) move past E. jubatus rookeries in Oregon on their way to breeding rookeries in Southern California. Introgression by male Z. californianus could potentially explain the difference in size of Oregon E. jubatus relative to other E. j...

Studies of the resident community of bottlenose dolphins ( Tursiops truncatus ) of Sarasota Bay, Florida, have been conducted for more than 50 years. Detailed histories have been collected for resident individuals through integrated observations, systematic photographic identification surveys, tagging and tracking, catch-and-release health assessments, remote biopsy sampling, and stranding response. This has produced a unique...

Rough‐toothed dolphins ( Steno bredanensis ) have a global tropical and subtropical distribution with oceanic, neritic, and island‐associated populations. To inform conservation and management for this species, we used sequences from the mtDNA control region ( n = 360), mitogenomes ( n = 19), and six nuclear introns ( n = 35) to provide multiple lines of evidence to critically evaluate the potential taxonomic status of rough‐t...

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...

Organochlorine (OC) pesticides and polychlorinated biphenyls (PCBs) have been detected in a variety of marine mammal species at levels associated with adverse health effects. Little is known about OC levels and impacts on health in pinnipeds with different life histories. We determined the health and levels of 18 OC pesticides and 16 PCB congeners in blubber samples from 20 Steller sea lions and 39 Pacific harbor seals strande...

We examined bone mineral density (BMD) in the pectoral flipper of the common bottlenose dolphin, Tursiops truncatus . These data addressed the need to define a comprehensive target site for osteodensitometric assessment and to provide a descriptive bone density data set for this species. We analyzed 388 radii from 279 bottlenose dolphins using dual energy X‐ray absorptiometry (DXA), the accepted standard in human medical studi...

Harbor porpoise (Phocoena phocoena) diets are predominantly comprised of small fish species (<30 cm) and squid. However, predation on larger species (up to 63 cm) occurs, raising the question of increased risk of asphyxiation associated with this behavior. Literature was reviewed and stranding data from 1983 to 2020 from the U.S. West Coast (including California, Oregon and Washington) were searched for cases of prey-related a...

In 2006–2007, an unusually high number of harbor porpoises ( Phocoena phocoena ) stranded along the Washington and Oregon coastlines. Spatiotemporal analyses were used to examine their ability to detect clusters of porpoise strandings during an unusual mortality event (UME) in the Pacific Northwest using stranding location data. Strandings were evaluated as two separate populations, outer coast and inland waters. The presence...

Muscle samples from 105 marine mammals stranded along the Oregon and Washington coasts (2002–2009) were tested for levels of total mercury (THg) by Cold Vapor Atomic Fluorescence Spectrometry. The THg present is in the form of the highly toxic methylmercury. After normalizing tissue to 75% water weight, Steller sea lions and northern elephant seals exhibited the highest mean concentrations of THg followed by harbor seals, harb...