for return of tags. The straight Hne distance be- 

 tween release and recovery locations indicated 

 the minimum distance travelled (called "net 

 movement") for fish recovered in the ocean. A 

 series of connected straight line tracks were used 

 to estimate net movement of fish recovered in 

 locations where a single line could not be used 

 (e.g., recoveries in Puget Sound). Straight line 

 distance travelled in the ocean was added to dis- 

 tance travelled upstream to estimate net move- 

 ment for fish recovered in river systems. Approx- 

 imate latitudinal change was used to estimate net 

 movement of fish for which an accurate recovery 

 location was not known (e.g., "recovered off Coos 

 Bay"). Net migration rate was estimated by divid- 

 ing net movement by days between release and 

 recovery. 



Results and Discussion 



Numbers of fish tagged and percentages recov- 

 ered are summarized in Table 1 for coho and Chi- 

 nook salmon released in different years. Recovery 

 rates were similar for maturing coho (mean 8.6%, 

 range 6-12%) and chinook (mean 9.4%, range 4- 

 22%) salmon. These are similar rates to those 

 found for these two species in other studies 

 (Table 1). 



Numbers of fish recovered in different areas 

 from releases off Oregon, Washington, and Van- 

 couver Island are given in Table 2. Simplified 



migration patterns are shown in Fig. 1. Recover- 

 ies of coho salmon released off Oregon were 

 mainly (81%) from the Columbia River and Ore- 

 gon. Only 11% were recovered in the Strait of 

 Juan de Fuca or Puget Sound. This distribution 

 differs from Van Hyning's (1951) finding that 

 47% of coho salmon tagged between June and Au- 

 gust from Cape Lookout, OR, to the Columbia 

 River were recovered in Puget Sound. Recoveries 

 of coho salmon released off Washington were 

 more widely distributed and 46% were recovered 

 from the Columbia River to Cape Flattery, 20% in 

 Oregon, 23% in the Strait of Juan de Fuca or 

 Puget Sound areas, and 11% in British Columbia. 



Estimated net migration of coho salmon be- 

 tween release and recovery (including upstream 

 migration for those recovered in freshwater) aver- 

 aged 181 km and ranged from 7 to 657 km 

 (Fig. 2A.) Most coho salmon were recovered 

 within 150 days of release. The two fish recoverd 

 after 330 and 380 days were released as juveniles 

 and recovered the following year as adults. 



Net migration rates of the maturing coho 

 salmon tagged in coastal waters were generally 

 very low and ranged from 0.1 to 20.4 km/day with 

 a mean rate of 3.6 km/day (Fig. 2B). Coho salmon 

 recovered in the open ocean off Oregon, Washing- 

 ton, or Vancouver Island (circles) had only 

 slightly higher mean rates of movement than 

 those recovered in the Strait of Juan de Fuca or 

 Puget Sound areas (triangles) or those recovered 



Table 2. — Recovery areas of fagged coho and chiinook salmon released off Oregon, 

 Washington, and the west coast of Vancouver Island. 



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