The average size and age of chinook salmon (Oncorhynchus
tshawytscha) caught in commercial fisheries along the Pacific Coast
of North America have decreased substantially in this century. These
declines might be caused in part by changes in size and age at
maturity within the stocks contributing to those fisheries. Upriver...
Early ocean residence is assumed to be a critical period for juvenile Pacific salmon Oncorhynchus spp. However, the specific mechanisms influencing growth and survival in the ocean have not been identified for most populations. Therefore, three hypotheses regarding the relationship between early marine residence and subsequent survival of mid-upper Columbia...
In a paper now in press as a Bulletin of the U. S. Fish and Wildlife Services the writer has discussed the downward trend of the catch of Columbia River Chinook salmon since 1920 and has stated that the decline is doubtless an indication that the runs of this species...
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...
A study of the fishery problems raised by the construction of the Grand Coulee Dam on the upper Columbia River was done. Part of the study was to estimate the number of salmon taken in commercial fishery for the purpose of comparing this with the number counted as they passed...
A study was undertaken in the fall of 1948 by the Oregon Fish Commission to determine the possible presence and importance of a delay in the migration of adult chinook salmon (Oncorhynchus tshawytscha) at Bonneville Dam on the Columbia River. Approximately 650 chinook were captured, tagged, and released at the...
This thesis addresses the costs of implementation of the Endangered Species Act (ESA)
in the particular case of Snake River chinook salmon. Unlike most previous listings under
the act, restoration of Snake River salmon will have impacts on a very broad array of
industries and user groups over a region...
Samples, consisting of scales, length and weight measurements, and sex determinations of chum, pink, and silver salmons, were taken from the commercial catch in the Columbia River in 1914. Five hundred eighteen chum scales were examined. All fish had gone to sea early in their first year; and 70.5 percent...
Chinook salmon returns to the Columbia River basin have declined due to impacts of a growing human population, despite significant mitigation expenditures. Consequently, fisheries managers have become focused on recovery and long-term viability of at-risk populations. A viable population depends, in part, on the connectivity and quality of diverse habitat...
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Daniel L. Bottom
Chinooksalmon returns to the ColumbiaRiver basin have declined due
Pacific Coast estuaries provide important rearing habitats leading to improved growth and survival for juvenile chinook salmon. However, research has suggested that juvenile salmon have little use for estuarine habitats in the Columbia River. To further understand salmonid recovery needs in estuaries, I compared historical and contemporary life history patterns...