[fraser] PACIFIC SALMON 215 



the margin. A month later the scales on the majority of the fish were 

 too much worn to be used for growth calculation. Here again the 

 nature of the scales serves a good indication of the amount of deterior- 

 ation in the fîesh, and their story corroborates the statement that 

 when the dog salmon get to the mouth of the river they are no longer 

 suitable for food, or at any rate are of very low grade. 



Summary and Conclusions 



Of the 1916 salmon examined, three types, according to the time 

 of migration to the sea, were in evidence. Included in the first of 

 these, those that had migrated during the first spring after being 

 hatched, about the time when the yolk was absorbed or shortly after, 

 were a small number of Fraser river sockeye, approximately two- 

 thirds of the springs, and all the humpbacks and dogs. Of these, the 

 sockeye seemed to gain little by the early descent to the sea, as they 

 did not grow very rapidly in the first year and in the later years lost 

 all the little excess they had over those of the stream type hatched 

 at the same time, so that in the fourth year they are little, if any, 

 larger than the stream type fish. The springs and the dogs started oflf 

 almost alike, but after the first year the spring had the greater growth 

 and became the bigger fish. In the case of the springs, the great 

 advantage gained over the stream type fish of the same year class, in 

 the first year, is kept throughout life so that the sea type spring is 

 practically one year ahead of the stream type hatched at the same 

 time. The humpbacks made the greatest growth of all in each of the 

 two years of life but the Rivers inlet fish grew more in each year than 

 the Comox fish. 



Included in the second type, those that migrated during the second 

 spring after being hatched, were all of the Rivers inlet sockeye, the 

 large majority of the Fraser river sockeye, about one-third of the 

 springs and all of the cohos. The springs and the cohos grew more 

 during the stay in fresh water than the sockeye do, and the Fraser 

 river sockeye grow more than the Rivers inlet sockeye. In all these 

 cases with the exception of the Rivers inlet sockeye, the increase in 

 length for each year in the sea decreased in each succeeding year. In 

 the Rivers inlet sockeye, the growth in the first year at sea was scarcely 

 three-fourths that of the second year. 



Included in the third type, those that remained in the fresh water 

 over two years before migration, there were but a few among the Fraser 

 river sockeye. As these grew little in either years in the fresh water, 

 they were much the same size when mature as the one year stream 

 type hatched one year later. 



