SUTHERLAND: DISTRIBUTION OF STEELHEAD TROUT 



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Figure 6. — Tagging locations and recovery areas (like symbols) of individual steelhead trout tagged by U.S. agencies, 

 1957-69. Directional movements of three individual fish are shown by arrows. 



northern British Columbia were tagged as far 

 south as lat. 50 °N, and some that were recovered 

 in California were tagged as far north as lat. 

 53 °N. Thus the two widely separate stocks 

 intermingled over at least 3° of latitude. Stocks 

 from the area that includes the Columbia River 

 were tagged over the latitudinal range of 45°N 

 to 53° N and west to long. 174°45'W. Recover- 

 ies from other streams were well represented 

 within this range. 



The directional movement of steelhead trout 

 from offshore to inshore varied among the stocks 

 of the various geographical regions. In inter- 

 preting migration routes, it is assumed that the 

 fish travel in a direct route from tagging site to 

 point of recovery. All fish recovered in California 

 and southern Oregon were tagged north of the 

 point of recovery, indicating a southeasterly 

 directional movement. The migration routes of 

 fish recovered in northern Oregon and Wash- 

 ington were essentially easterly to south- 

 easterly. Two fish, however, were tagged south 

 of the point of recovery, indicating movement in 

 a northeasterlv direction. Fish recovered in 



British Columbia were tagged in nearly equal 

 numbers north and south of the points of 

 recovery. The directional movement of these fish, 

 therefore, varied from southeasterly to north- 

 easterly. 



Timing of recoveries indicates that both 

 "summer-run and winter-run" steelhead trout 

 were tagged. Withler (1966) described summer 

 steelhead trout as those which enter and ascend 

 streams during May through August and win- 

 ter steelhead trout as those which enter from 

 mid-October to as late as May. Based on the 

 percentage composition of the tagged fish 

 recovered in coastal streams, summer steelhead 

 trout stocks predominated in British Columbia 

 and winter steelhead trout stocks predominated 

 in Washington, Oregon, and California. Of the 

 23 tagged fish recovered in British Columbia, 

 20 (87% ) were captured from May through 

 Sei)tember and 3 (13%) from January through 

 March. Of the 41 tagged fish recovered in 

 Washington, Oregon, and California, 29 (71% ) 

 were captured from December through March 

 and 12 (29%) from May through September. 



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