76 



FISH AND GAME COMMISSION. 



the outline given are dependent entirely upon the records we obtain — 

 and Ave are acquiring the very best possible. ' ' 



Some of the details of the work in carrying out this program at 

 San Pedro and Monterey are given by Elmer Higgins and 0: E. Sette 

 in C^u^iFORNiA Pish and Game, Vol. 6, No. 4, pp. 180-182 and in sub- 

 sequent articles in the same publication b}^ Mr. AV. P. Thompson. 



Por a period of two years daily samples of the fish have been taken 

 as they were unloaded from the boats at the cannery, careful measure- 

 ments made, weights taken, and the sex and state of maturity observed. 

 This mass of data has been systematized and analyzed so that now 

 iniportant results are being obtained. 



In determining the age and rate of growth of the sardine it was found 

 that the scales as an index of the age were very unsatisfactory. It was 

 necessary therefore to get this knowledge by reverting to the old 

 method of tabulating the length frequency of the fish. (See California 

 Pish and Game, Vol. 5,. No. 2, p. 53.) 



Fig. 24. Drawing showing the way in which young salmon have been marked by 

 removing the adipose and right ventral fins. Returned marked salmon are 

 furnishing much valuable evidence as to the life history and habits of this, the 

 finest of- food fishes. 



By this method' the rate of growth of the fish during their first four 

 or five years has been worked out, and a paper on this pliase of the 

 sub.ject by Mr. Higgins is ready for publication. This ability to 

 determine the rate of growth and the abundance of the year classes 

 which go to make up the various sizes of commercial importance, is 

 not only of great importance from the conservation standpoint, but 

 it will also be of great importance to the industry in that it will enable 

 us to forecast the relative abundance of year classes which will be 

 drawn upon fcr canning. This applies more especially to the quarter 

 oil pack, as the small fish used for the quarter oil cans, come mostly 

 from one year class. 



It has been determined from the data gathered that our sardines, 

 as we had suspected, do show the phenomenon of dominance of year 

 classes, and for that reason the sardine industry may be subject to 

 great natural fluctuations in abundance. It is extremely important, 

 for the good of the fishery, that we be in a position to know just what 

 thr' finctuations mean. To foretell that certain sizes will be plentiful 



