Radiotelemetry was used to study the seasonal movements and habitat use of adult westslope cutthroat trout Oncorhynchus clarki lewisi in Roberts
Creek and Rail Creek, headwater tributaries of the John Day River, Oregon,
from September 2000 to December 2001. The objectives were to (1)
describe adult cutthroat trout life history...
The present study investigated the neurocrine and neuroendocrine control of locomotor activity, habitat choice, social behavior, and migratory behavior in juvenile chinook salmon (Oncorhynchus tshawytscha). This was achieved by the manipulation of three neurotransmitter systems; serotonin (5-HT), dopamine (DA), y-amino-n-butyric acid (GABA) and the neuropeptide corticotropin-releasing hormone (CRH). Chemicals were...
The social sciences have the capacity to contribute to natural resource management through investigations of human dynamics associated with the environment. Sense of place (SOP), the formed relationships between an individual and the environment, has been considered a fundamental aspect of human well-being and can contribute to more holistic understanding...
The importance of hormone reservoirs in mature teleost eggs is
unknown. To elucidate the effects of hormones on embryonic development,
steelhead trout eggs, Oncorhynchus mykiss, were immersed in either cortisol,
testosterone, or thyroxine at two different stages of development. Elevated
concentrations of cortisol were detectable in the trout eggs or...
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...
Recent research conducted throughout the Northern California Current (NCC) on the ecology of Pacific salmon (Oncorhynchus spp.) indicates that variable ocean conditions affect the community composition of zooplankton in the nearshore environment which, in turn, can affect the quality of prey for fish, sea birds and mammals. Interannual variability in...
Steelhead and rainbow trout are common names for marine-migratory (anadromous) and freshwater-resident forms of Oncorhynchus mykiss, a partially migratory salmonid fish. Anadromous and resident forms are sympatric and can produce offspring with a life history different from their own (i.e., steelhead parents can produce rainbow trout offspring and vice versa)....
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...
Northern anchovy (Engraulis mordax) are a dominant forage fish in the California Current large marine ecosystem (CCLME). However, little is known about northern anchovy abundance, distribution, age structure, or population fluctuations relative to ocean conditions in the eastern boundary upwelling system off the U.S. West Coast. This thesis includes three...
Lahontan cutthroat trout (LCT) (Oncorhynchus clarki henshawi) are currently limited in their distribution to a patchwork of small isolated populations, the result of habitat degradation and natural variation in landscape and in-stream conditions. The objectives of this study were to determine how landscape level topographic features influence LCT distribution patterns....