Past studies of the Oregon and Washington coast have shown a rapid change in the coastal ocean conditions with the onset of upwelling in spring. This process, called the spring transition marks the change from winter to summer conditions along the west coast of Unites States. To examine the interannual...
An investigation has been made of several physical parameters of the effluent plume of the Columbia River as it enters the Pacific
Ocean. Radioactive material in trace amounts enters the Columbia River from the Hanford nuclear reactors at Richland, Washington. One of these nuclides, chromium -51, has been used to...
Euphausiids constituted the major food of five co-occuring species of rockfishes (Sebastes spp.). Copepods, decapods, cephalopods, amphipods, fishes and other pelagic prey were also consumed but were
less important to the overall diet. Two species, S. flavidus and S. diploproa, were relatively euryphagous, utilizing a high number of prey taxa....
A series of factorial experiments were conducted using eyed oyster larvae (Crassostrea gigas) reared at a commercial hatchery in Netarts, Oregon. The objectives of the study were to obtain the highest percentage of setting larvae and the best survival of the spat. Experiments on the combined effects of temperature and...
The copepod population in Oregon coastal waters was examined from 116 oblique plankton tows taken during 1962. Quantitative Clarke-
Bumpus samplers were used and stations ranged from 5-105 miles from shore along four hydrographic lines. Forty-six species of copepods were identified. The total adult population varied according to distance from...
Fifty-two one-meter plankton net samples from four stations off Newport, Oregon, were examined for composition and abundance of euphausiids and copepods. They provided data on dominance, species associations and environmental relationships. The euphausiid-copepod population off Oregon is composed of 12 numerically dominant species. These species occurred in most of the...
This thesis investigates the behavior of major inorganic nutrients (P, N, Si), trace metals (Mn, Fe), and alkaline-earth metals (Ba) within Tillamook Bay over seasonal cycles and under a range of river discharge conditions from October 1997 through December 1999. Located in the Pacific Northwest region, Tillamook Bay is an...
The Oregon continental shelf waters are typically characterized by four to five major upwelling events that occur between May and October. The upwelled water is rich in nutrients, which fuels an increase in phytoplankton biomass. The onset of El Nino, however, can disrupt the normal physical processes along the Oregon...
Inner-shelf circulation and mechanisms of across-shelf transport of water masses were examined using seven years of observations collected by the Partnership for Interdisciplinary Studies of Coastal Oceans (PISCO) program, a long-term monitoring effort along the central Oregon coast. Since 1998, moored velocity and hydrographic measurements have been obtained during the...
An empirical statistical model is developed that relates the non-tidal motion of the ocean surface currents off the Oregon coast to forecasts of the coastal winds. The empirical statistical model is then used to produce predictions of the surface currents that are evaluated for their agreement with measured currents. Measurements...