FRENCH and BAKKALA: NEW MODEL OF OCEAN MIGRATIONS 



Figure 13. — Distribution and abundance of age .1 sockeye salmon in August 1967, 1968, and 

 1969 as shown by catches of Japanese research vessels. 



immatures into the Bering Sea in August. In 1969 

 catches were much larger in August from long. 

 172=30' to 177'30'E than in 1967 or 1968, 

 suggesting the presence of large numbers of age 

 .1 fish that were progeny of the 1965 record run 

 to Bristol Bay. Evidence from age composition of 

 these catches (mainly age 2.1 fish) also indicated 

 that they were predominantly Bristol Bay fish 

 as originally suggested by Machidori. The location 

 of these fish in the central and western Bering 

 Sea indicates that routes of travel from the North 

 Pacific to the Bering Sea were through passes 

 west of Adak Island. Large numbers of age .1 

 fish, probably of Asian origin, were taken in the 

 Bering Sea west of long. 175''E in September 

 (Figure 14), but sampling did not extend far 

 enough eastward to determine if Bristol Bay fish 

 still remained in the Bering Sea. 



From the above analysis we conclude that some 

 proportion of the age .1 fish from Bristol Bay 



inhabit the central and western Bering Sea in 

 August and that their abundance in the Bering 

 Sea varies with the abundance of the total stock. 

 Although some of the Bristol Bay immatures 

 move north into the western Bering Sea, the large 

 numbers of immatures remaining south of the 

 Aleutians indicate that many of the Bristol 

 Bay sockeye remain in the North Pacific Ocean 

 and maintain a broad east-west distribution 

 throughout the summer. At the time large catches 

 of age .1 sockeye were taken in the Bering Sea 

 — from 12 to 30 August 1969 — large catches were 

 also being made south of Adak Island from 1 to 

 15 August (French, Bakkala, Dunn, and 

 Sutherland, 1971). Catches by Japanese and 

 United States research vessels in August 1970 

 better illustrate this point (Figure 15). The rela- 

 tive abundance of age .1 sockeye was generally 

 higher throughout the area south of the Aleutian 

 Islands than it was at stations fished in the Bering 



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