Response of aquatic vertebrates to increased pool habitat complexity due to abundance of large wood was evaluated experimentally in three streams in the Cascade Mountains of Oregon. No difference in aquatic vertebrate density was detected among treatments, though there was a trend of increasing aquatic vertebrate density with increasing large...
Various mollusks, including small bivalves and gastropod snails, are a common food source for intertidal crabs. Prey opening techniques used on hard-shell prey are dependent on claw size and morphology. For example, large, strong claws can crush a snail outright while smaller, weaker claws leave characteristic peels, pulls and upper...
Dramatic declines in many species of demersal fishes off the West Coast have resulted in the designation of nine commercially important species as being overfished. While the causes of those declines are not clearly understood, the fact remains that a paucity of life history and abundance data exists for many...
Research on the distribution of juvenile salmonids in streams has been dominated by studies examining small areas over short periods. However, information relevant to freshwater influences on population persistence is likely to derive from longer-term, multi-scale studies. Relationships were examined among juvenile anadromous salmonids, their freshwater habitat, and landscape characteristics...
Field investigations were implemented to study the interrelationships between streamflows and salmonid production during the summer-fall low flow period in two natural stream channels. Elk Creek, near Cannon Beach in Clatsop County, was the site selected for intensive investigation.
Construction of streamflow control and diversion facilities was completed in November...
Riparian areas are eco-tones where aquatically- and terrestrially-derived insect biomass is exchanged between habitats, presenting consumers with new sources of energy, and resulting in a reciprocal subsidy. The relative contribution of energy exchange and the
resulting impacts on vertebrate riparian consumers, such as fish or birds, remains poorly understood. We...
By the early 1990s, the citizens of Tillamook County recognized that environmental problems facing Tillamook Bay threatened the very future of those residing here. Declining fish runs meant loss of income for commercial fishermen, tackle shops, hotel owners, and other fishing - dependent businesses. Decreasing water quality meant violations of...