30 FISH AND GAME COMMISSION 



Pacific mackerel and sardines, the commission set minimum size limits 

 for all three species, effective in December, 1947. 



During the biennium our research work on Pacific mackerel centered 

 on studies interrupted by the war, and on routine sampling of the com- 

 mercial catch at Los Angeles Harbor and at Newport Beach. The 

 sampling program included both measurement of fish, and the collection 

 of otoliths (bony ear structures) for use in age determination. Age 

 studies progressed satisfactorily. Otoliths collected were read as was 

 part of the backlog accumulated during the war. Results of the tagging 

 and racial studies were analyzed and compiled in manuscript form. In 

 both cases, the field work was done before the war. These studies indicated 

 that the Southern California fishery draws to some extent on the mackerel 

 population from as far south as central Lower California, but that fish 

 from southern Lower California and the Gulf of California in all prob- 

 ability contribute little or nothing to the fishery. Tag returns demon- 

 strated a free movement of fish between northern Lower California, 

 Southern California, and Central California. Toward the close of the 

 biennium work was started on an analysis of scoop boat catches to cover 

 the years since 1939. 



The great increase in importance of the jack mackerel lead to the 

 establishment of a limited study of this species in 1947. The official name 

 of the fish was changed from "horse mackerel" in the summer of 1947 

 because the old name proved a handicap in disposing of the increased 

 pack. Before making the change, each processor was asked to show his 

 preference for one of several acceptable substitute names. The consensus 

 favored jack mackerel, and it was given official sanction. 



Studies in progress at the close of the biennium included sampling 

 of the commercial catch, age determinations, and a population study. 

 Scales of jack mackerel did not prove satisfactory in age work, so otoliths 

 (collected as part of the sampling program) are being used with apparent 

 success. 



SALMON 



The salmon resource was first developed as a commercial fishery 

 under the Mexican Government, and before that time had been important 

 in the food economy of many Indian tribes. This fishery is today the 

 most important in Northern California; and in the light of the dis- 

 coveries of the last two years, it must be recognized that its latent value 

 has not yet been realized. 



The 1946 catch of 13,639,000 pounds slightly exceeded tluit of 1945, 

 and was the largest of which there is a reliable record. The following year, 

 1947, saw the production of 11,428,000 pounds, a catch that is among 

 largest of which we know (see Figure 13) . 



The bureau's salmon tagging program of the past bieiuiium has 

 given for the first time two independent measures of the total run into 

 the Sacramento-San Joaquin River system. These measurements indicate 

 that the run of king saliDon is far larger than had been supi)osed. They 

 also indicate that the catcli-to-ruii ratio is smaller than for any other 

 major stream for which records have been published. These figures, when 

 compared with those of the runs in other rivers, indicate that the poten- 

 tial values have been but partially developed. 



