We evaluated the effects of the McNary Dam transportation system on emigrating fall and spring chinook smolts using physiological indices of stress (e.g., plasma cortisol, hepatic glycogen, leucocrit, interrenal cell nuclear diameter) and performance tests (e.g., saltwater challenge, secondary stress challenge, disease resistance). We also conducted controlled experiments in a...
The cultural and ecological values of Pacific lamprey (Lampetra tridentata) have not been understood by Euro-Americans and thus their great decline has almost gone unnoticed except by Native Americans, who elevated the issue and initiated research to restore its populations, at least in the Columbia Basin. They regard Pacific lamprey...
This study examined the potentially stressful
effects of tagging juvenile rainbow trout Oncorhynchus mykiss
with passive integrated transponder (PIT) tags by measuring
short-term (<120-h) changes in plasma concentrations of
cortisol and hepatic heat shock protein 70 (hsp70). In a
laboratory experiment, plasma cortisol levels were measured
in fish before they...
Juvenile Oncorhynchus mykiss migrate extensively in freshwater during fall. We used individual tagging to study the spatial origin, influences, and outcomes of fall migration on fish that emigrated from summer rearing tributaries during fall (early-emigrants) and those that did not (late-emigrants) in the South Fork John Day River, Oregon. Fall...
Rotary screw traps are used throughout the West Coast of North America to capture emigrating juvenile salmonids. Calibrating the capture efficiency of each trap is essential for valid estimates of fish passage. We released Passive Integrated Transponder (PIT) tagged Oncorhynchus mykiss upstream of a rotary screw trap in the South...
In a study of cumulative effects of riparian disturbance by grazing on the trophic structure of high desert trout streams, watersheds with greater riparian canopy had higher standing crops of rainbow trout Oncorhynchus mykiss, lower daily maximum temperatures (range, 16-23°C compared with 26-31°C), and perennial flow. Watershed aspect influenced the...
In this report, a response is given to the charge of this study. Volume I: Summary Report includes a synopsis of the technical considerations followed by the main findings and recommendations. The full technical background for these summary statements is given in detail in Volume II: Technical Background Report, and...
Deciding which textbook to assign to students is often a very difficult decision. A textbook should offer more than just a synthesis of information, it should inspire curiosity, cause one to reflect, and provide a framework for making decisions. Most reviews reflect a single opinion, sometimes based on personal preferences....
The purpose of this pilot program was to determine whether or not forward looking infrared (FLIR) videography could be used to develop thermal maps of the mainstem Klamath River to access habitat limitations due to high stream temperatures for fall chinook salmon (Oncorhynchus tshawytscha).