A fixed survey design with a randomized depth component and a large rope trawl that fished surface waters at a speed of approximately 5 knots was used to estimate the abundance of juvenile coho salmon Oncorhynchus kisutch in the Strait of Georgia. The estimates of 4.2 million juveniles in September 1996, 3.0 million in September 1997, and 3.0 million in September 1998 were minimal because the catchability of the net was probably lower than that used in the analysis. In 1997, by using hatchery‐marking percentages, we estimated that 3.4 million wild coho salmon smolts entered the Strait of Georgia from Canadian rivers. The estimates of juvenile abundance made in September 1997 were considerably larger than the estimated total returns in 1998, indicating that the marine mortality in fall and winter is an important component of the total marine mortality determining the final strength of the brood year. The use of surveys for estimating juvenile coho salmon abundance is a contribution to the understanding of the processes that regulate salmon abundance naturally and can potentially provide management information well in advance of any fishery.

A stochastic growth model is presented to represent the growth in carapace length of the Alaska king crab (Paralithodes camtschatica Tilesius). Two submodels are combined to yield the growth model: (1) growth increment as a function of premolt length and molting history and (2) a probabilistic model of frequency of molting by age, premolt length, and molting history. The results of a computer simulation of the growth model are presented. Frequency of ages at various lengths and frequency of lengths at each age are given. Frequency of molting during early life was found to greatly influence growth rate. Key words: king crab, growth, length, stochastic model growth increment, molting, growth model

Eggs of Pacific halibut were incubated under various environmental conditions. Optimum hatching occurred over a temperature range from 6 C to 8 C, whereas temperatures of 3, 10, and 11 C were lethal. Development time from fertilization to 50% hatching varied from 250 h (9 C) to 320 h (6.5 C). Salinity effects on hatching were not as critical as temperature, as long as eggs were floating during the incubation period. Light intensity between 5 and 15 lux did not affect hatching success, but high light intensity (15 lux) and red and blue light (5 lux) produced high levels of larval abnormality. Simulated transport of unfertilized eggs indicated that the eggs can be safely moved and that fertilization rate is acceptable during the first 12 h after collection.

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