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The Speed oe Migrating Salmon in the Columbia River. 



By Chas. W. Greene. 



(Abstract.) l 



In the solution of this problem I devised a scheme whereby individual 

 fishes could be given individual tags that would render identification ab- 

 solutely certain if the fish should be recaptured. This plan was nothing 

 more or less than the use of the conventional stock-marking aluminum 

 buttons. These buttons are light and cannot be torn apart and they carry 

 serial numbers on one face; on the other can be placed such special 

 marks as one may select. 



On August 14, 190S, I marked fifty-nine fish at Sand Island, just with- 

 in the mouth of the Columbia River. These fish were liberated in the 

 river in the hope that some would be retaken, and thus we might glean 

 the story of their migration. The fish were marked by inserting num- 

 bered buttons through the caudal fin. 



Seventeen of the fifty-nine fish liberated were retaken and reported 

 to me ; sixteen buttons were also returned to me. The fish were retaken 

 along the river from a point four miles below where they were liberated 

 up to the Dalles of the Columbia, just below Celilo Falls, a total dis- 

 tance of two hundred and fourteen miles. Near the upper limit quite a 

 number of fish were taken and six of these had traveled a distance which, 

 when rated, gives an average individual speed of from six and one-third 

 to seven and one-half miles a day. 



The following table is constructed to show the actual time from lib- 

 eration to recapture, the distance covered, the probable time consumed 

 in the straight-away run on a basis of the speed of number 76 (seven and 

 one-half miles), and the days unaccounted for. My view is that these un- 

 accounted days are chiefly spent in the lower estuary of the river in be- 

 coming acclimated to the fresh water. 



1 This investigation was undertaken in cooperation with the United States 

 Bureau of Fisheries. This abstract is published by the consent of and with the 

 approval of the II. S. Commissioner of Fish and Fisheries. 



