Many highly exploited ecosystems are managed on the basis of single-species demographic information. This management approach can exacerbate tensions among stakeholders with competing interests who in turn rely on data with notoriously high variance. In this case study, an application of diet and dive survey data was used to describe...
Juvenile steelhead are known to associate with shiner groups, though they also compete for food. Steelhead form dominance hierarchies within cohorts and aggressively defend feeding territories against all other fish. This study focused on the differential effect of shiner competition on steelhead of different social standing.
Survival of subordinate juvenile...
The lingcod (Ophiodon elongatus) is an important groundfish species in both recreational and commercial fisheries of the Northeastern Pacific. It is a large, fast-growing, generalist predator of invertebrates and fishes. In response to concerns that lingcod may limit populations of rockfishes (Sebastes spp.), I compared the diets of 375 adult...
Water quality problems have been identified in the Chehalis River in the vicinity of Centralia and Chehalis since the 1960's. In 1992, the Washington State Department of Ecology listed four Chehalis River segments, three segments of the Newaukum River, two segments of the Wynoochee River, and three other tributaries -...
A case study was performed in 2000 and 2001 to characterize the thermal pattern of four morphologically similar eastern Oregon streams and to identify the physical and environmental factors that expressed significant and functionally viable relationships with stream temperature (daily maximum, daily minimum and daily rate of heating). Stream and...
Since the early twentieth century, manufacturers of toxic products have attempted
to discredit research linking their product with disease. At the same time they have manufactured their own science designed to minimize risks associated with their products. Much of this activity has been conducted by or through corporate attorneys, endeavors...
Over one third of the earth’s land surface has been modified to some extent for agricultural purposes. The large global footprint of agriculture, combined with the knowledge that existing reserve networks are likely insufficient for long-term conservation of native biodiversity, has necessitated that agricultural systems contribute to conservation of native...
Relatively recent increases in ponderosa pine abundance have effected unprecedented changes to ecosystem structure and function. Efforts to restore ponderosa pine systems are often focused on the manipulation of tree structure and the re-introduction of a more natural fire regime. Successful restoration should also incorporate understory components but information addressing...
Ergovaline is an ergot alkaloid produced by the symbiotic endophyte Epichloë coenophiala which can colonize varieties of the cool-season grass tall fescue (Festuca arundinacea). It is the principle toxicant responsible for the vasoconstrictive and reproductive sequelae seen in “fescue toxicosis” in livestock which consume forage exceeding the threshold of toxicity...