The 1988 status of yellowtail flounder stocks off the U.S. coast
of the Northwest Atlantic is assessed using U.S. and distant water
fleet commercial fishery statistics and Northeast Fisheries Center
bottom trawl survey data. Assessments of Southern New England and
Georges Bank stocks are revised using virtual population analysis of...
Natural and gabion modified habitats containing coho salmon
(Oncorhynchus kisutch) were observed and measured seasonally in East
Fork Lobster Creek, a fifth order stream in western Oregon. Coho
salmon usually inhabited backwater and secondary channel pools in
winter. Large wood debris complexes and undercut banks were the
primary sources of...
Early ocean residence is considered a critical period for juvenile salmon although specific survival mechanisms are often unidentified and may vary by species or life stage. Columbia River spring-run Chinook salmon Oncorhynchus tshawytscha abundance has declined dramatically since the early 1900s. To elucidate mechanisms of early marine survival, we tested...
Wavelet analysis is an analytical and modeling tool for optimizing sampling efficiency and accuracy, particularly in the context of designing long-term, large-scale monitoring plans. As a pattern analysis method that accommodates and preserves non-stationarity, wavelet analysis provides novel visualization and analytical capabilities for increased insight into interactions between multi-scalar heterogeneous...
Being able to individually follow fish <40 mm in length is a challenge for fish research. In the present study we examined whether the use of visible implant elastomer (VIE) tags is suitable for research on first-feeding rainbow trout Oncorhynchus mykiss raised under laboratory conditions. We assessed the effect of...
Infectious pancreatic necrosis (IPN) is an acute, contagious disease of trout fry
and fingerlings caused by viruses of the family birnaviridae. IPN disease usually results
in mortality that is inversely proportional to the age of the fish. While many studies
have been carried out to increase our understanding of IPN,...
Genetic differences between early and late forms of
Alaskan chinook salmon (Oncorhynchus tshawytscha) were
identified using two genetic approaches: mitochondrial
DNA (mtDNA) analysis and protein electrophoresis. The
study populations consisted of early- and late-run chinook
salmon in each of the Kenai and Kasilof rivers in Alaska,
and a single population...
We described and predicted spatial variation in marine migration (anadromy) of female Oncorhynchus mykiss in the John Day River watershed, Oregon. We collected 149 juvenile O. mykiss across 72 sites and identified locations used by anadromous females by assigning maternal origin (anadromous versus non-anadromous) to each juvenile. These assignments used...
Models are commonly used to assess and predict wildlife response to management practices. Model validation is essential if managers are to use them with confidence. Fifteen forest bird-habitat relationship models were developed by biologists using data collected from private forestland in southwest Washington. These models predict species' probability of occurring...
Collaborative fisheries research provides a mechanism for integrating the unique knowledge, experience, and skills of fishermen and scientists. It is a joint intellectual endeavor that begins with the inception of a project and continues until its final stages, with each group having mutual investment in-and ownership of-the project. Collaborative fisheries...
The occurrence of band-tailed pigeons (Columba fasciata) three mineral sites in Western Oregon was studied during the summers of 1974-1976. Objectives of the study were o: determine seasonal patterns of utilization of mineral sites by pigeons of different sex and age classes; determine productivity of pigeon populations associated with Mineral...
Protein microcapsules (PM) were developed as a tool for investigating aspects of dietary protein utilization by mussels, Mytilus edulis trossulus. Digestion of PM in vitro by protease, trypsin, amylase and extracts from the gut of mussels varied significantly depending on the type of protein encapsulated or whether carbohydrates were added...
Species associations of fifteen major commercial groundfish species in the
northeastern Pacific ocean and their spatial and temporal characteristics were studied
using Oregon bottom trawl logbook data, 1987 to 1993. Screening procedures were used
to remove questionable data from the original logbook files, which resulted in the
exclusion of information...
Relative use by pronghorns (Antilocapra americana) of 16 range sites was studied during summer and fall of 1971 and 1972 on Hart Mountain National Antelope Refuge, an area of high desert
rangeland in south central Oregon. A Relative Use Index was developed based upon 1533 observations of pronghorns located on...
Reported are results of a study of otolith nuclei as a means to separate juvenile steelhead trout (Salmo gairdneri) from juvenile rainbow trout (S. gairdneri) which co-exist in the lower Deschutes River, Oregon. An intensive recreational fishery necessitated development of a technique for separation so that the impact
of the...