Diets of juvenile coho Oncorhynchus kisutch and Chinook O. tshawytscha salmon
are made up primarily of winter-spawning fish taxa in the late-larval and early juvenile stages that
are undersampled in plankton and larger trawl nets. Although we have no direct measure of the
availability of fish prey important to juvenile...
The interplay of natural selection and genetic drift, influenced by geographic isolation, mating systems and population size, determines patterns of genetic diversity within species. The sperm whale provides an interesting example of a long-lived species with few geographic barriers to dispersal. Worldwide mtDNA diversity is relatively low, but highly structured...
We combine high-resolution bathymetry acquired using the Autonomous Underwater Vehicle ABE with digital seafloor imagery collected using the remotely operated vehicle ROPOS across the axial valley of the Southern Explorer Ridge (SER) to infer the recent volcanic and tectonic processes. The SER is an intermediate spreading ridge located in the...
Marine protected areas (MPAs), ideally, manage human uses that threaten ecosystems, or components of ecosystems. During several recent MPA designation processes, concerns have arisen over the scientific justification for no-take MPAs, particularly those that restrict recreational fishing for pelagic species. An important question is: under what conditions might recreational pelagic...
We compared brood sizes among adult female Euphausia pacifica Hansen, 1911 from 3
populations in the North Pacific: Puget Sound, Washington, USA; Toyama Bay, Japan; and the Oregon coast, USA. Additionally, we used multiple linear regression models to compare the interspecific brood size as a function of female length and...
A network of autonomous underwater hydrophones is used to monitor acoustic activity associated with Hunga Ha'apai-Hunga Tonga volcano during a period of 15 months. The data provide a continuous record spanning a surtseyan eruption (VEI 2) in March of 2009, which input ~10¹³ J of acoustic energy into the ocean...
Continued stock declines in marine fisheries have resulted in a search for more risk-averse management approaches. In response, the Sustainable Fisheries Act of 1996 mandates habitat protection, bs catch reduction, and stock rebuilding. These changes emphasize precaution, and imply a shift in focus from maximizing yields to minimizing ecological impacts...
Cell lines were established from spleen and heart tissues of a juvenile white sturgeon Acipenser transmontanus and designated WSS-2 and WSH-1, respectively. Isoenzyme analyses of both lines confirmed their host of origin. Both lines were hypotetraploid and possessed micro- and macrochromosomes. The modal chromosome number for the WSS-2 line was...
Little is known about the nutrition or lipid metabolism of cold-water crabs, particularly in the North Pacific. We undertook a 2-part study to understand more completely the energetics and nutritional requirements of juvenile red king crab (RKC; Paralithodes canusehaticus). First, we investigated changes in proximate composition, total lipids (TLs), lipid...
While much effort has been directed at determining the spatial scales of adaptation in thermal reaction norms for growth, it is widely assumed that these reaction norms have high temporal stability. Water temperatures in the Gulf of Alaska in 2007 were the coldest on record since the mid-1970s and we...
Cephalopods are increasingly viewed as sentient animals that require the same welfare consideration as their vertebrate counterparts. In this study, an observational welfare assessment tool developed by the EU Directive was revised to be species-specific for the giant Pacific octopus, Enteroctopus dofleini. This E. dofleini health and welfare assessment tool...
Pacific rockfish experience high discard mortality when captured owing to a condition called barotrauma,which is caused by the change in pressure during capture. This condition appears to be species specific at the macroscopic level; however, little is known about the microscopic tissue-level effects of barotrauma. Determining whether tissue-level injuries are...
Euphausiid krill play a critical role in coastal and oceanic food webs, linking primary producers to upper trophic levels. In addition, some species support commercial fisheries worldwide. Despite their ecological importance, the genetics of these important species remain poorly described. To improve our understanding of the genetics of these ecological...
We evaluated how the use of bait as a fish attractant influenced the species and size composition 20 of demersal fishes viewed with a stereo video lander, at 160 sampling sites at Stonewall Bank, a 21 deepwater rocky reef complex in Oregon waters. We also studied the effectiveness of stereo...
Intense infections of the gill pathogen Dermocystidium salmonis were associated with mortality of prespawning chinook salmon Oncorhynchus tshawytscha in several Oregon rivers in 1988. The occurrence of the pathogen in returning adult chinook salmon was monitored in several coastal Oregon stocks from 1989 to 1993. Although the prevalence of the...
Fluorescein has been used for rapid and sensitive detection of fish skin and corneal ulceration. Effective use of the fluorescein test requires knowledge of conditions that might cause misleading interpretations or otherwise interfere with test reliability. Examination of fish health and the clinical workup often require tricaine as one of...
We evaluated the external signs of barotrauma and 48-h post-recompression survival for 17 54 canary and 81 yelloweye rockfish captured at depths of 46-174 m, much deeper than a 18 similar prior experiment, but within the depth range of recreational fishery catch and 19 discard. Survival was measured using specialized...
Requirements are growing for peer review of the science used for governmental management decisions. This is particularly true for fisheries science, where management decisions are often controversial. The National Oceanic and Atmospheric Administration's National Marine Fisheries Service instituted the Center for Independent Experts (CIE) in 1998 as a national peer-review...
Tag and recovery programs can provide valuable information on population size and exploitation rates in fishes. Passive integrated transponder (PIT) tags are ideal for use in such programs because they provide identification of individual fish and are invisible to anglers, circumventing problems with nonreporting of tags. Our objective was to...
Although the adverse impact of pathogens on salmon populations in the Pacific Northwest is often discussed and recognized, little is currently known regarding the incidence and corresponding significance of delayed disease-induced mortalities. In the study reported herein, we surveyed the presence and prevalence of selected micro- and macroparasites in out-migrant...