119 



Introduction 



The question of how , to -measure the status of Columbia Basin 

 salmon stocks has always been in^xjrtant, however the need to answer 

 this question has taiken on an air of urgency since stocks of 

 Chinook salmon in the Snake Basin joined the federal list of 

 threatened species earlier this year. The federal listings, and 

 the fact that salmon stocks in the Columbia Basin have been 

 repeatedly declared to be at risk (i.e., NPPC 1986), add in^etus to 

 the discussion of appropriate meeisures of stock status. 



The diversity of measurement techniques available in the form 

 of visual counts at hydroelectric dams, and surveys of spawning 

 activity made by foot smd from the air, make the con^arison of 

 stock status for wild eaOmon populations problematic. Hatchery 

 populations have counts of individuals returning to- the facility 

 that, in principle, are directly con^Jcirable . At present the need 

 has not been met for a comprehensive survey of wild salmon 

 populations that ea5>loys a quantitative measure of wild stock 

 health and permits meaningful con^jarisons among stocks. The 

 present effort is focused on chlnook salmon, however the approach 

 envisioned should be applicable to all species on which there are 

 similar types of data. 



