The Columbia Basin once supported a diversity of native fishes and large runs of anadromous salmonids that sustained substantial fisheries and cultural values. Extensive land conversion, watershed disruptions, and subsequent fishery declines have led to one of the most ambitious restoration programs in the world. Progress has been made, but...
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...
The species composition, distribution and concentration of ichthyoplankton off the central Oregon coast in the NE Pacific Ocean were examined during 2000 and 2002 to investigate annual, seasonal, vertical, and cross-shelf variability. Larval concentrations were also analyzed in relation to water temperature and salinity. The 281 samples collected from 5...
Riverine plumes in nearshore coastal waters are areas of enhanced production and accumulation of prey and may increase availability of food during a critical period of juvenile salmon survival and hence serve as a nursery area for these juveniles. Physical and biological sampling was conducted along a cross-shelf transect through...
Ecological interactions between natural and
hatchery juvenile salmon during their early marine
residence, a time of high mortality, have received little
attention. These interactions may negatively influence
survival and hamper the ability of natural populations to
recover. We examined the spatial distributions and size
differences of both marked (hatchery) and...
Eastern boundary current (EBC) upwelling zones are among the most productive of marine ecosystems globally and have been generalized in terms of their food web structure. Little empirically based evidence exists to suggest that there is any one form of trophic control of EBC systems and, because of logistical constraints,...
Estimating the stock proportions of mixed-stock fishery samples by means of genetic stock identification has played an important role in the management of salmon fisheries. In addition, stock identification of individual fish has applications for population studies, forensic cases, and management issues. We examined 11 microsatellite DNA loci in 84...
Nearshore hypoxia along the coast of Oregon and Washington is a seasonal phenomenon that has generated concern among scientists studying this temperate upwelling ecosystem. These waters are affected by coastal upwelling-induced hypoxia mainly during late summer and fall, but the effects of low oxygen levels on fish and invertebrate communities,...
The role of each habitat fish use is of great importance to the dynamics of populations. During
their early marine residence, Chinook salmon (Oncorhynchus tshawytscha), an anadromous fish
species, mostly inhabit estuaries but also use sandy beach surf zones and the coastal ocean.
However, the role of surf zones in...
The Fukushima Daiichi power station released
several radionuclides into the Pacific following the March 2011
earthquake and tsunami. A total of 26 Pacific albacore (Thunnus
alalunga) caught off the Pacific Northwest U.S. coast between
2008 and 2012 were analyzed for ¹³⁷Cs and Fukushima-attributed
¹³⁴Cs. Both 2011 (2 of 2) and...