Distribution and life history characteristics of lacustrine-adfluvial bull trout (Salvelinus
confluentus) were described in the North Fork Skokomish River Basin (including Lake
Cushman, a reservoir) from 1994 to 1996. Day snorkeling was conducted in the river to
determine initiation of the bull trout spawning migration, abundance of spawners, and
duration...
Although differences between selective pressures in hatcheries
and streams have been theorized to cause genetic divergence between
hatchery and wild salmonids, evidence of this is lacking. This study
was initiated to document the presence or absence of genetic change
in hatchery and wild stocks by characterizing genetic traits in fish...
The distribution of herring (Clupea harengus pallasi) in
the Northeast Pacific extends from southern California to
northern Alaska. Studies on variation in herring life-history
are limited to local
characteristics and recruitment
populations or relatively restricted regions of the Northeast
Pacific. In this study I assessed herring life-history
patterns and recruitment...
Various aspects of the energetic response to handling stress in juvenile
coho salmon (Oncorhynchus kisutch) were examined. Fish were subjected to
four different handling stressors in a Blazka-style respirometer. Stressed fish
had rates of oxygen consumption that were higher than controls. The
magnitude of the increase ranged from 139 to...
I examined habitat electivity and movement patterns of adult spring chinook salmon at microhabitat and channel unit spatial scales, and seasonal to annual temporal scales in seven streams in the Grande Ronde, John Day, and Imnaha basins. The objective was to compare habitat use and availability among streams, channel units,...
Responses of juvenile steelhead trout to changes in stream habitat resulting from an instream habitat rehabilitation project in Meadow Creek, Oregon were measured from 1991 through 1992 and compared to pre-treatment data from 1987 through 1990. Sixty nine pool-forming, and 59 channel-stabilizing log structures were constructed by the U.S. Forest...
This study examined features of deep pool (>0.8 m mean depth) used by
adult summer steelhead in Steamboat Creek (1991-1992). Steamboat Creek had
a heterogenous thermal profile, with some segments exceeding preferred
temperature of steelhead. Deep pools were scarce (4% of the total habitat units)
and 39% of them were...
The spawning habitat associated with fall chinook salmon (Oncorhynchus
tshawytscha) redd clusters was investigated in the Hanford Reach of the Columbia River.
A conceptual spawning habitat model is proposed that describes how geomorphic
features of river channels create hydraulic processes, including hyporheic flows, that
influence where salmon spawn in unconstrained...
Because riparian canopy controls most energy inputs to stream
ecosystems, it directly affects the structure of aquatic food webs and the
ecological processes that govern interactions among trophic levels. This
study addresses the interdependence among riparian canopy, benthic
community structure, and the carrying capacity of high desert streams for
salmonid...