Figure 1.— Commercial fishing areas for 

 Dungeness crab off Washington, Oregon, and 

 Cahfornia. (Pacific Fishery Management 

 Council (1979).) 



Before 1973, the California salmon season (coho 

 and Chinook) opened on 15 April, although few coho 

 were landed before June because of a minimum size 

 restriction. As Oregon and Washington hatchery 

 coho became available, a substantial increase in the 

 hook and release of sublegal ("shaker") fish developed 

 during the latter half of April to the middle of Juna 

 In an attempt to reduce the shaker problem, the 

 season opening for coho was delayed until 15 May 

 and the minimum size was reduced in 1973 (O'Brien 

 and Lesh 1975). 



California coho catches generally peak in July, then 



drop sharply in August, 2 mo before the salmon 

 season closure The midsummer decline is attributed 

 to the northward exodus of fish returning to their 

 natal stream to spawn (Fry 1973). It is however 

 unclear when and by what route these fish entered 

 California waters. 



A general migration model (Loeffel and Forster 

 1970; Godfrey et al. 1975; Hartt 1980) proposes that 

 newly emigrated west coast coho move immediate- 

 ly northward into the Gulf of Alaska, then during 

 winter, undertake a southeasterly migration which 

 brings them back into California, Oregon, and Wash- 



683 



