REPORT OF STATE BOARD OF FISH COMMISSIONERS. 



105 



The superabundance of enemies is probably the most important 

 factor in limiting the number of salmon. Their enemies during the 

 egg and alevin stage have been mentioned above. After beginning to 

 swim, the young salmon is a very active fish, and during his migration 

 down the rivers to the ocean, when the young from the hatcheries are 

 first exposed to the same dangers as those from the natural spawning 

 beds, he is in no great danger from birds or fishes, with the exception 

 of the Dolly Varden trout. While in fresh Avater the young salmon is 

 too small to receive the attention of fish ducks, which feed largely on 

 sculpins or minnows, while the cormorants feed on carp and (in Alaska) 

 on trout that are larger than the young salmon. 



We do not know the enemies in salt water, except that the quinnat 

 feeds to some extent on young salmon. But other enemies are 

 numerous enough. I recently examined 500 adult salmon for the pur- 



QUINNAT, OR SACRAMENTO RIVER, SALMON. 



pose of determining the number that had been injured in any way, as 

 shown by scars, scratches, and scale abrasions, with the result showing 

 that 11 per cent had received at least some slight injury, and that 5 per 

 cent carried scars indicating that they had had really close calls for 

 their lives. When 11 per cent have been in danger, and when 5 per 

 cent have barely escaped with their lives, how many must there have 

 been that did not escape? It seems certain that the salmon taken by 

 the fishermen, numerous though they may be, are only a few in com- 

 parison with the number that perish before they meet the fishermen. 

 Artificial propagation must not be held responsible for the safety of the 

 fish among these dangers. And whatever the output of young from the 

 hatcheries or from natural spawning beds, there are sure to be years of 

 scarcity. 



Artificial propagation of salmon has not yet reached such proportions 

 as to entirely supplant natural propagation, with the exception of the 

 work on the Sacramento River, and until such condition is reached, 



