424 American Fisheries Society 



plans are promptly worked out to meet the situation the sal- 

 mon will be exterminated in the streams affected and the fate 

 of the Atlantic salmon in the Connecticut River be repeated 

 on the Pacific Coast.* 



The value of any particular run of red salmon depends 

 not only on possibility of maintaining the stream as a fish pre- 

 serve, or of protecting the fish against the changes involved in 

 the utilization of the water for one purpose or another, but 

 also on the condition of the fish on their arrival at the spawn- 

 ing grounds. This may be due in some degree to the length 

 of the trip from the sea to the spawning grounds but it is 

 more largely determined by the character of the stream. If 

 the salmon have to surmount difficult falls and tumultuous 

 rapids, if they must at points fight against a current that is 

 almost insurmountable and are held up by narrows that can 

 be traversed only at certain stages of water, then they are 

 likely to reach the spawning grounds battered and torn, and 

 with energy largely spent. In fact as stated above, in extreme 

 cases a certain percentage of the run does not succeed in sur- 

 mounting these natural obstacles and so never reaches the 

 spawning grounds or discharges its reproductive function. 

 Evidently then an important factor in determining the proper 

 policy is the character of the stream in so far as it determines 

 the condition of the fish and their ability to reach the spawn- 

 ing grounds. It is, of course, feasible to improve a given 

 stream by blasting away rocks or buildng artificial pools as rest- 

 ing places for fish at difficult falls and rapids. Such improve- 

 ments have been made and have proved very valuable in a 

 few cases but in general it is not possible to meet the expense 

 of making over a difficult stream. 



In determining the relative value of salmon streams one 



* Since this paper was prepared I have received a work by James Ritchie on 

 "The Influence of Man on Animal Life in Scotland" in which these questions are 

 discussed and evidence presented in a remarkably vivid fashion to show the in- 

 fluence of river obstructions on Scottish salmon fisheries and of the river pollution 

 also on the same species. The discussion is illustrated by two striking maps. No 

 one interested in these problems should fail to consult Dr. Ritchie's volume. 



