PEARCY and FISHER: MIGRATIONS OF COHO SALMON 



summer of all years. Their abundance, as that of 

 age 1.0 coho salmon, also increased during the 

 summer off Washington where they intermingled 

 with age 1.0 coho salmon. Because the Oregon 

 region included the release locations of all age 0.0 

 coho salmon, our figures provide no information 

 on southward movements of these fish. 



The mean lengths of both age 0.0 and 1.0 coho 

 salmon increased from the southern to the north- 

 ern areas during most months. Larger age 0.0 and 

 1.0 coho salmon were caught off Washington than 



Oregon during the late summer, 1981-84 (Fig. 2), 

 providing corroborative evidence for northward 

 migration of coho salmon. Larger, and pre- 

 sumably older, fish were found farther to the 

 north than smaller fish. 



Despite northward movements, many yearling 

 coho salmon did not migrate out of the sampling 

 area, but remained in coastal waters off Oregon 

 and Washington during the entire summer. Mean 

 coastwide catch per set of yearling coho salmon in 

 August 1981 and September 1982, 1983, and 1984 



1982 



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JUNE 



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SEPTEMBER 



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FORK LENGTH (cm) 



Figure 2. — Continued. 



179 



