CONTENTS 



Introduction 1 



Methods 2 



Pink salmon 3 



Indices of brood year abundance 3 



Predator-prey relationship 3 



Surface sea temperature 4 



Individual size 4 



Chinook salmon 4 



Indices of brood year abundance 4 



Hatchery production 6 



Surface sea temperature during period of out-migration 6 



Upwelling during period of out-migration 6 



Upwelling during current season 6 



Previous fishing success 6 



Coho salmon 6 



Indices of brood year abundance 6 



Hatchery production 7 



Environmental conditions during preemergence 7 



Summer streamflow during year i — 2 



Oceanographic conditions affecting juvenile survival 



Oceanographic conditions influencing catchability 



Jack returns 7 



Average individual weight and monthly growth 



Results 



Pink salmon 7 



Chinook salmon 8 



Levels of effort 8 



Indices of brood year abundance 8 



Hatchery production 8 



Previous fishing success 9 



Prediction of ocean catches 9 



Coho salmon 9 



Levels of effort 9 



Indices of brood year abundance 10 



Hatchery production 10 



Environmental conditions 10 



Average size and growth increments 10 



Jack counts 10 



Prediction of ocean catches 10 



Discussion 10 



Acknowledgments ,. 11 



Literature cited 11 



Figures 



1 . Salmon statistical catch areas 2 



2. Annual commercial troll catch of chinook salmon in the Coastal Washington area vs. plant of fall brood year 

 groups i - 3 and i - 4 combined by lower Columbia River hatcheries, 1 963-75 8 



3. Canadian commercial troll catch of chinook salmon in areas C, 21, and 23 during April through May vs. plant 



of fall brood year groups / - 3 and /' -4 combined by lower Columbia River hatcheries, 1963-75 8 



4. Annual Washington ocean sport catch of chinook salmon, 1964-75 and that predicted from the regression of 

 catch on total Columbia River hatchery releases of fall chinook salmon of brood year groups /— 3 and i-4 

 combined 9 



5. Canadian commercial troll catch of chinook salmon in areas C, 21, and 23 during April through May vs. 

 natural log of number of jacks in the area 20 purse seine catch during August of year /— 1, 1963-75 9 



6. Annual commercial catch of coho salmon in the Columbia River and Coastal Washington areas, 1966-75 and 



that predicted from Equations (2) and (3) 10 



