This annual calibration report describes calibration procedure for the Pacific Salmon Commission (PSC) Chinook Model and summarizes the results of the May 1997 calibration (9702). The calibration process estimates the abundance (or cohort size) of the 30 model stocks. The abundances for broods that contributed to catch and escapement for the years 1979 through 1996 are estimated from historical time series of catch by fishery, and stock-specific estimates of escapement, terminal runs, hatchery production, and coded-wire-tag (CWT) recoveries. In addition, 1997 cohort abundances are estimated using preseason forecasts provided by management agencies or model estimates of average survival rates.

This report includes:

1. estimates of stock composition of total fishing mortality in the SEAK troll, NCBC troll, WCVI troll, and GS sport and troll fisheries; and
2. for each stock, the percent of total fishing mortality occurring in the SEAK all gear, NCBC all gear, the WCVI troll, and GS sport and troll fisheries.

Calibration 9702 will remain unchanged, but other calibrations may be done to update the model as improved forecasts of abundance and/or model enhancements are identified.