Movements of individual maturing salmon off 

 Oregon and Washington are still poorly known. 

 In this paper we examine migration after tagging 

 of salmonids collected during purse seine cruises 

 off the Oregon and Washington coasts from 1982 

 to 1985 and off the west coast of Vancouver Is- 

 land, B.C., in 1984. 



Methods 



Maturing and juvenile salmon were collected 

 by purse seine during May 1982, 1983, and 1985; 

 June 1982-85; July 1984; and September 1982-84. 

 Coho salmon, Oncorhynchus kisutch, were classi- 

 fied as maturing or juvenile, based on the length- 

 frequency distribution of the catch in each month. 

 The distribution was usually bimodal and the di- 

 vision between juvenile and maturing coho 

 salmon was about 300 mm FL in May and June, 

 360 mm FL in July, and 420 mm FL in August 

 and September. Chinook salmon, O. tshawytscha, 



<400 mm in all months were arbitrarily classi- 

 fied as juveniles. 



Numbered orange Floy^ tags were applied with 

 a Dennison Mark II tagging gun between the 

 pterygiophores just below the dorsal fin of fish 

 anesthetized with MS-222. Fish were allowed to 

 recover for a few minutes in tanks with circulat- 

 ing saltwater and then were released into the 

 ocean. Date and location of release was recorded 

 for each tagged fish. Condition of the fish after 

 handling varied, but most swam vigorously in the 

 recovery tank and rapidly swam away when re- 

 leased. However, some scale loss almost always 

 occurred and for some individuals was extensive. 



Information on movements of coho and chinook 

 salmon was obtained from subsequent recoveries 

 in ocean and terminal fisheries and on spawning 

 grounds or at hatcheries. No reward was offered 



2Reference to trade names does not imply endorsement by the 

 National Marine Fisheries Service, NOAA. 



Table 1. — Summary of mark and recovery data for coho and chinook salmon tagged in the ocean off 

 Oregon, Washington, and the west coast of Vancouver Island. 



820 



