26 DEPARTMENT OF THE NATAL SERVICE 



each of the first two years. When, however, the four-year class of 1917 is compared 

 with the three-year class of 1916 (both of them spawned in 1913) no such difference 

 appears. Looking at the question from this standpoint, it would appear that those 

 of the 1913 class that spawned in their third year were not larger at that time than- 

 those that remained over to spawn in the fourth year but rather that the 1913 class, as 

 a class, consisted of larger fish than the 1912 class. If that continues to hold good, 

 then, the 191-t class must consist of still larger fish. It is scarcely possible though that 

 each succeeding year class will consist of larger and larger fish. It might be possible 

 that increase and decrease work in cycles on account of the conditions of getting food 

 supply, or other matters on which growth depends, getting gradually better or worse, 

 but it would take examination for a series of years before that could be determined. 



Summary and Conclusions. 



Among the 1917 salmon there were the three different types according to the 

 time of migration to the sea, as in 1916. A larger percentage of spring salmon were 

 of the sea type (78-2 per cent as compared with 65-4 per cent). In all localities from 

 which sockeye were obtained, those of the one-year stream type made up almost the 

 whole number, although in each case the two-year stream type and the sea type were 

 represented. Oniy 15 of the former (less than 1 per cent) and 124 of the latter (7-5 

 per cent) were found altogether, the largest number in each caee from the Fraser 

 river. The cohos were all of the one-year stream type, and the humpbacks and dogs 

 all of the sea type. 



The spring salmon of either type did not differ materially iii rate of growth from 

 those of previous years. There has not been anything thus far to indicate that any 

 one-year class has had more rapid growth than any other. Four six-year fish of the 

 stream type were obtained. The sex ratio changed from a ©light predominance of 

 males to an excess of females (especially pronounced in the sea type). 



The three types of fish were represented in the sockeye from each locality. Those 

 of the two-year stream type were all in their fifth year and those of the sea type all 

 in their fourth year with the excei^tion of a three-year-old from Sauch-en-auch creek. 

 The fish of the one-year stream type were nearly all in the fourth year, the percentage 

 ranging from 93-8 at Deepwater bay to 99-7 off Victoria. The remainder were in the 

 fifth year. 



In every feature the sockeye, collectively and individually, from Deepwater bay, 

 off Victoria and from the Fraeer river, were similar. Those from Sauch-en-auch 

 creek were similar in general type to these others but were smaller .a'ld showed less • 

 average growth in length in each year. They agreed so well with the smaller fish 

 from the other localities that it is credihle that the race had become smaller through 

 continued elimination of the larger memhers. The route that these fish take must be 

 the same at the beginning as it is for those that pass through Deepwater bay, but 

 evidently they turn aside from Johnstone strait through Chancellor channel and 

 through some of the passages ^nearer the mainland, while the direct route through 

 Discovery passage and on to the Fraser river is taken by the others. 



The average length of the 1917 sockeye was somewhat less than that for 1916, 

 hence it may be that the fish of the quiadrennial run are somewhat smaller than those 

 of other years in the cycle. As there is also a greater predominance of four-year fish, 

 the number to the case of canned salmon is greater than in other years. 



Since all the soak eye were of the same general type one should scarcely expect to 

 find any material difference in the weight-length ratio, nor did any such appear. 



As in other years, all the coho were of the one-year stream type. Although they 

 were obtained from four different localities, Quathiaski, Lasqueti, Nanaimo and 

 Fraser river, there were no indications of four races of fish. There may readily be 

 two, one that staj's in the strait of Georgia and "neighbouring waters throughout the 



