During the course of this year-long study, 203 baited traps were set, resulting in the capture of 2632 sablefish, of which 1450 were tagged. An additional 1051 sablefish from other sources were sampled, making a total of 3683 sablefish analyzed. Catch rates at 50 fathoms (fm) were consistently low, and higher catch rates indicated that sablefish were most abundant at 300-750 fm. Sablefish showed a regular increase in size with depth, with the higher percentage of 'large' fish found at 500-750 fm. Seasonal variations were demonstrated at 100 fm by elevated catch rates and the presence of larger fish during the summer months, whereas little seasonality appeared in deeper waters. Squid proved to be a more effective bait than anchovy both in initial attractiveness and longevity. One and two-day soak times with squid bait yielded the best catches per trap, however 4-hr soak times yielded the best catch rates when standardized to a 48-hr period. Overall, female sablefish predominated in this study, with males most numerous among small fish. Sablefish in Monterey Bay spawned between November and February in waters deeper than 300 fm. Among fish of a given size, the more ripe individuals tended to be found in deeper waters. Preliminary tag returns indicated that sablefish in Monterey Bay are generally localized. Sablefish traps were very selective at depths from 300-750 fm, while at 50 fm, incidental species greatly outnumbered sablefish.
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