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Plasma corticoid concentrations in juvenile chinook salmon (Oncorhynchus tshawytscha) netted and confined in a small live-cage rose from approximately 100 ng/ml to about 500 ng/ml in 24 h, then fell to 250 ng/ml at 48 h. In juvenile chinook salmon dip netted into a bucket containing aerated water and sampled serially at 90-s intervals, plasma corticoids increased from < 10 ng/ml to approximately 100 ng/ml in 20 min. In juvenile cutthroat trout (Salmo clarki clarki) acclimated to 13 C and subjected to a rapid increase in water temperature to 26 C, plasma corticoid concentration increased from about 20 ng/ml to 70 ng/ml in 25 min and remained elevated for more than 3 h. Juvenile cutthroat trout acclimated to diurnal temperature cycles (13-23 C) had no sabstantial changes in plasma corticoid concentration throughout the cycles. Juvenile cutthroat trout acclimated to 23 C had •;he same initial corticoid concentration as cutthroat trout acclimated to 9 C. When both groups were subjected to identical netting and confinement, the corticoid concentrations in fish from the two temperatures responded in a similar fashion until 70 rain of confinement when trout from the warmer water failed to maintain increasing corticoid concentrations.

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Pacific ocean perch, Sebastes alutus, stocks in the northeastern Pacific Ocean off the coasts of Oregon, Washington, and British Columbia experienced severe damage from overexploitation in the mid-1960's. Catch limits were imposed during 1978. Fishermen questioned the need for these limitations on the basis of lack of precision in biomass estimates provided by research surveys and because of the recruitment of a relatively strong 1970 year class. To respond to these concerns and to provide an updated biomass estimate with better precision than for previous estimates, a trawl survey was conducted between 22 March and 2 May 1979. The survey was designed and conducted jointly by the Northwest and Alaska Fisheries Center of the National Marine Fisheries Service, the Washington Department of Fisheries, and the Oregon Department of Fish and Wildlife with the primary objective of obtaining information needed for improved management of this species. The objective was attained through stratification of the survey area using commercial fishery data and results from previous research. The precision of the biomass estimate for the United States' portion of the International North Pacific Fisheries Commission's Vancouver area was improved by 31% over the estimate resulting from the 1977 rockfish (Sebastes spp.) survey. Review of the survey data indicated that (1) these stocks remain in serious condition despite an apparent increase in abundance attributable to the strong 1970 year class, and (2) the stock north of the Columbia River was composed of a wider range of sizes and ages than the stock off the coast of Oregon. Pacific ocean perch, Sebastes alutus, stocks in the northeastern Pacific Ocean experienced severe damage from overexploitation in the mid-1960's. Prior to 1965, the resource was harvested exclusively by Canadian and United States vessels. Combined Canadian-United States landings in the Charlotte, Vancouver, and Columbia areas (Fig. 1) of the International North Pacific Fishedes Commission (INPFC) peaked in 1965 at 14,127 t. Soviet vessels began fishing these stocks in 1965 and Japanese vessels entered the fishery in 1966, sharply increasing the landings of Pacific ocean perch. Peak production for all nations in the Charlotte-Columbia areas combined was reached in 1966 at 72,126 t. Catches in these areas the following year totalled 66,981 t. These harvests exceeded prior maximum annual har-

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