46 FISH AND GAME COMMISSION 



definite information can be applied to the formative engineering plans 

 of the Project, to insure the protection of the fish life with a minimum 

 additional expenditure to the United States Reclamation Service. Our 

 studies will continue for at least another year in order to complete all 

 phases of this investigation now under way. Even after the various 

 water projects of the Central Valley are constructed, the biological 

 work will be continued in order to ascertain the effectiveness of the 

 fish protective methods adopted. 



In addition to the salmon research being done in connection with 

 the Central Valley investigations, tagging of salmon in the ocean has 

 been undertaken. The returns from this marking will make it possible 

 to trace the movements of salmon in the sea and to determine to which 

 stream the fish return from the ocean. 



A statistical analysis of the California salmon fishery for the years 

 1916 to 1939 was also made to determine the relative abundance of the 

 salmon populations. The results will be beneficial in managing- this 

 resource in an effort to rehabilitate the once important salmon fishery 

 of the State. 



ABALONE 



During the period 1938-1940, investigative work was undertaken 

 and partially completed on the abalone fishery of the State. The 

 abalone areas from Point Conception to Monterey were surveyed by 

 means of diving to evaluate the condition of the population of red 

 abalones, especially the relative abundance of various sizes. Very 

 young abalones (one mm. in diameter) were taken in Carmel Bay, 

 whereas a scarcity of very young and also of legal sized abalones was 

 found in most of District 18. Studies will be conducted to determine 

 the spawning habits, the possible drift of eggs and larvae, and the 

 rate of growth, so that better management of this fishery may be 

 effected. To obtain the highest yield possible from this fishery, its 

 utilization should be managed by "farming" certain localities; that 

 is, permitting commercial diving in one region for a time and trans- 

 ferring activities to another area after the surplus abalones of the legal 

 size of eight inches and over have been harvested. Knowing the 

 growth rate and the movement (if such occurs) of eggs and larvae, 

 each designated area can be "farmed" or fished on a high productive 

 basis without endangering the basic spawning reserve. 



Results of the diving survey have strengthened the belief that 

 there should be no conflict between the noncommercial abalone fish- 

 ermen and commercial fishermen, as investigations continue to confirm 

 the fact that abalones do not move from deep to shallow water but 

 are stationary during their life after the shell is formed. 



OYSTER 



Oyster culture activities in California during the past two years 

 have shown a very marked progress. The Bureau of Marine Fisheries 

 is aiding the industry in developing the native (or Olympia) oyster 

 grounds in Humboldt Bay, and these oysters are now beginning to 

 be of marketable size. 



Two large companies are actively engaged in the cultivation of 

 native oysters in Humboldt Bay, and in addition there are several 

 smaller operators. In 1938, the oyster spat catch was normal, and 



