THIRTY-FIRST BIENNIAL REPORT 



17 



This bureau has successfully operated 28 hatcheries and 15 egg- 

 collecting stations during the biennium, producing over 62,000,000 

 trout, varying from 1^ to 4 inches in length, and 10,000,000 salmon. 

 At the close of the period covered by this report 35,000,000 trout were 

 on hand for the 1930 distribution. 



The success of the work of this bureau is indicated by the insistent 

 demand for additional hatcheries, but it is felt that rather a definite 

 limit has been reached in the expenditure of funds for fish cultural 

 work from the revenues which are now being received. 



The problem of securing eggs is becoming exceedingly difficult with 

 the continued periods of low precipitation. Added to this is the feeling 

 which exists in several sections that all eggs taken from any stream 

 system should be returned to the same system. Inasmuch as it is well 



Fig. 



Unloading bass at Calipatria, Imperial County, Califorii'a. for stocking 

 Salton Sea. Photo courtesy of Robert Hays, October, 1929. 



established that from 70 to 80 per cent of the eggs taken by artificial 

 methods are successfully hatched and reared to sizes suitable for plant- 

 ing, as contrasted with evidence that only from 3 to 5 per cent of the 

 eggs from natural spawning produce fish of a similar size, it is our 

 opinion that the Commission is well justified in releasing to other por- 

 tions of the state eggs taken in any of our stream systems as long as 

 there are successfully planted in the parent streams more fish than 

 would have been naturally produced had no egg-taking operations been 

 undertaken. 



FISH RESCUE 



The Bureau of Fish Rescue has continued its program of saving, as 

 far as possible, all fish stranded bv receding waters or endangered by 



2—81166 



