Thesis (M.S.)--University of Wisconsin--Madison, 1983. / Typescript. eContent provider-neutral record in process. Description based on print version record. Includes bibliographical references (leaves 80-88).

Thesis (M.S.)--Oregon State University, 2010. / Printout. Includes bibliographical references (leaves 96-101). Also available on the World Wide Web.

Thesis (M.S.)--University of Alaska, Fairbanks, 2003. / "August 2003." Includes bibliographical references (leaves 29-34). Available also in electronic format on the Internet.

Graduation date: 1993

Thesis (M.S.)--Oregon State University, 1972. / Typescript (photocopy). Includes bibliographical references. Also available on the World Wide Web.

The abundance of the 1982 brood of juvenile coho salmon (Oncorhynchus kisutch) was determined in August 1983, and January and April 1984 at 20 study sites spread throughout Knowles Creek, an Oregon coastal watershed. The timing of emigration of juvenile coho from the watershed was monitored from October 1983 through June 1984. Condition factor, fork length, and gill (Na+K)-ATPase activity were measured in migrants, a captive group of Knowles Creek juvenile coho held in the laboratory, and nonmigrant fish periodically sampled from the stream. Skin guanine levels were also measured in migrant and nonmigrant groups. Juvenile coho abundance in January was significantly correlated with abundance in August. Wood volume and amount of undercut streambank were the pair of physical variables that best explained variation in the number of fish per square meter or per cubic meter in January. Two debris torrent ponds in the middle of the watershed contained large amounts of woody debris and were the most heavily used overwintering habitats for juvenile coho in the Knowles Creek. Few juvenile coho overwintered in the lower half of watershed, an area lacking woody debris. Peaks in outmigration occurred in November and May. Approximately 24% of the total number of migrants emigrated in November. Fish that reared in two of three third-order areas in summer, together with fish from the lower (fifth-order) half of the mainstem, were the first to leave the watershed. While lack of winter habitat may have been the cause of migration from the lower mainstem, low summer streamflows may have caused early migration from the low order sites. Gill (Na+K)-ATPase activity of migrants rose gradually from a low in January to a peak at the end of the study in June. Mean gill (Na+K)-ATPase activity of nonmigrants was only significantly lower than that of migrant fish during April. Gill (Na+K)-ATPase of captives was similar to that of nonmigrants until it peaked during the last two weeks in April, after which the activity fell below that of migrants or nonmigrants. Condition factor of nonmigrant fish was higher than either migrants or captives throughout the study. Migrant skin guanine levels rose sharply during the first two weeks in April and continued to rise until the end of the study in June. Approximately 8,300 juvenile coho, 44% of the estimated number of juvenile coho present in Knowles Creek in August, migrated from the watershed by the following June. An estimated 9% of the August population migrated as smolts after April 1. / Graduation date: 1986

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 198% of the control value, and appeared roughly related to the severity of the stressor. The post-stress increase in oxygen consumption also appeared to vary seasonally, with less of a stress effect on respiration observed in the spring as compared to the fall. Elevation in oxygen consumption following stress was largely eliminated within 1 h post-stress, but metabolic rate may have remained slightly elevated for an additional 2 h. Plasma cortisol and lactate titers also increased significantly following handling stressors. Oxygen consumption was positively correlated with both plasma cortisol and lactate after a moderate stressor, but no correlation was found after more severe stressors. Whole body lactate concentration was significantly elevated following stress, reaching levels almost 500% higher than controls. By 5 h post-stress whole body lactate had returned to control levels. The mechanism of excess post-stress oxygen consumption remains unclear. Fish given exogenous cortisol did not experience an increase in oxygen consumption, so it is unlikely that cortisol alone has a major effect on metabolic rate. Similarities between the energetic responses to both stress and exercise suggest that the results of exercise physiology may provide a basis for understanding the energetic response to stress. / Graduation date: 1993

Graduation date: 1983

Thesis--University of Wisconsin--Madison. / Typescript. Vita. eContent provider-neutral record in process. Description based on print version record. Includes bibliographies.

Thesis (Ph. D.)--University of Washington, 1981. / Vita. Bibliography: leaves [73]-80.