42 FISH AND GAME COMMISSION 



end of the season. Tlie advisory eomniittee also diseontinned its efforts 

 to develop a lony-range program of iiiaiiagenient. 



The increase during the last two seasons in the tonnages landed 

 resulted from the appearance on the fishing- grounds of two fairly 

 abundant groups of fish, those spawned in 1!)46 and 1947. During both 

 th(^ l!)48-49 and 1949-50 seasons, 80 percent of tlie fish came from these 

 two year classes. The 1947 group was more abundant than the 1946 and 

 will presumably continue to make a major contribution to the fishery in 

 the innnediately succeeding seasons. If no new abundant year classes 

 apjDcar on the fishing grounds, the present healthy condition in the indus- 

 try cannot continue for any great length of time. 



As a result of the efforts of the industry a coordinated program for 

 expanded sardine studies was set up under the direction of the Marine 

 Research Committee during the P^ortieth Bicnnium. This unifies the work 

 of the California Academy of Sciences, California Division of Fish and 

 Game, Scripps Institution of Oceanography and U. S. Fish and Wildlife 

 Service. Although initiated in the previous bicnnium the expanded work 

 at sea could not be started until vessels had been purchased and recon- 

 ditioned for the specialized studies. 



Routine sea investigations were begun in February, 1949, and have 

 been continued on a monthly basis since that time. The division 's research 

 ship M. V. N. B. Scufield participated in the first three of these cruises in 

 1949 and occupied the station lines from Point Conception south to the 

 central part of Baja California. After this time Scripps Institution and 

 U. S. Fish and AYildlife Service had sufficient vessels to carry on the 

 regular physical, chemical and biological sampling at sea and the N. B. 

 S CO field turned to other activities of the division. 



In September, 1949, the M. V. Yelloivfin was ready for operation 

 and she began the specific tasks assigned to the Division of Fish and 

 Game in the cooperative sardine investigations. From October until the 

 end of the biennium, with the use of sonar and recording fathometer, the 

 YeUowfin located schools of sardines in Southern and Central California 

 waters. Samples of the fish in these schools wei-e taker, and material for 

 age determinations and food studies collected. \Yhere schools were found 

 records of water temperatures, water samples and plankton samples were 

 taken. The purpose of this study is to determine the physical and chemical 

 conditions where sardine schools will be found, wliat kinds of food are 

 present and if the sardine shows a preference for particular types of 

 plaiiktonic food. 



In addition to the work at sea the staff continued its routine collec- 

 tion of data for an analysis of the size and age composition of the catch 

 and a measure of the success of the fishing fleet. Results of studies of the 

 return to the fisherman based on his average monthl}^ or weekly catch 

 had been published through 1942. These former studies were reviewed, 

 continued through the 1948-49 season and published as Fish Bulletin 

 No. 76, in the last six months of the biennium. Through the cooperative 

 study carried on with the U. S. Fish and Wildlife Service the 1948-49 

 and 1949-50 sardine catches were compiled by tons and numbers of fish 

 taken in each age group. These tables were published in the July, 1949, 

 and July, 1950, issues of California Fish and Game. 



