Genetic, ontogenetic, and environmental factors modified characteristic interrenal and glycemic responses to stress in juvenile salmonid fishes. During continuous confinement stress, plasma cortisol rose more quickly in chinook salmon, Oncorhynchus tshawytscha, acclimated to high rather than medium or low temperatures; hyperglycemia following either acute or chronic stress was also highest...
Hypotheses of phylogenetic and historical zoogeographic relationships of glyptocephalines (Glyptocephalus cynoglossus, G. zachirus, G. stelleri, Microstomus kitt, H. pacificus, H. achne,
Embassichthys bathybius, and Tanakius kitaharae) were constructed based on comparative anatomy and external morphology. The phylogenetic approach was cladistic and character polarity was
determined by using out-group comparison. One...
This study examines the ecology and dynamics of coho salmon (Oncorhynchus kisutch) in environments experimentally altered by logging. The objective was to evaluate processes that stabilize or regulate the populations. Two small watersheds in Oregon's Coast Range were logged in
1966, one clear-cut, the other patch-cut. A third adjacent watershed...
Long-term oceanographic and meteorological data were used to develop models that describe the observed variation in the recruitment of Pacific mackerel (Scomber japonicus) in the California
Current region. The models that were found to best describe recruitment included both density-dependent factors and environmental factors. Models incorporating only density-dependent factors
accounted...
Successful fertilization of fresh steelhead trout, pink salmon, kokanee, chum salmon, fall chinook salmon, and coho salmon eggs with cryopreserved sperm is reported in this thesis. A mean percent fertilization greater than 50 percent was achieved for all species tested except chum salmon. Differences in sperm viability from donor males...
Population dynamics of coastal cutthroat trout were studied in a controlled-flow section of Berry Creek, Oregon, from August 1972 to August 1973. All trout except the underyearlings were tagged to allow movement, survival and weight change of individual trout to be monitored. Fifty-eight percent of the tagged trout which were...
This is the first report on the susceptibility of salmonid fish to infection with the glochidia of the freshwater mussel Margaritifera. margaritifera using known numbers of parasites under controlled conditions. The relative susceptibility of six species of salmonid fish, 2O to 80 mm in total length, to glochidiosis was determined...
Numerous tests were applied to rainbow trout
of eleven months of age to determine whether
ascorbic acid is an essential element of the diet
of these fish. Although previous work had been
done on this question, conflicts in the results,
the large reliance upon abnormal symptoms such as
lordosis and...
The contribution of genetic effects to the variation in percent normal development observed in a bay mussel (Mytilus edulis L.) embryo bioassay was determined. A factorial breeding experiment
was accomplished in which 9 males were mated with 3 females. Each mating was repeated 10 times, yielding 270 mussel embryo cultures,...