SOME OBSERVATIONS ON THE GROWTH OF YOUNG 



SOCKEYES ' 



By Alexander Robertson 



Harrison Hot Springs, British ColumMa 



The depletion of the sockeye salmon is the most serious problem 

 confronting the fishing industry of the Pacific Coast of America, and 

 fish-cultural methods in connection therewith are very much in the 

 limelight at the present time. Provided that a sufficient number of 

 adult sockeyes are allowed to pass to the spawning grounds, which 

 may probably mean a complete cessation of sockeye fishing for a num- 

 ber of years, authorities all agree that increased protection during the 

 early life of the species is the remedy for the situation, but consid- 

 erable diversity of opinion exists as to how this is to be accomplished. 



Under ordinary circumstances, sockeyes remain in fresh water 

 for at least one year, but whether it is a rigid law of nature or merely 

 an expedient to attain a certain size before meeting the destructive 

 competition of the sea, it is hard to say. Anyway, it is conceded that 

 in certain cases, notably that of the Harrison Rapids sockeye of the 

 Fraser River, certain of them do proceed to sea as fry and that par- 

 ticular race of sockeyes does not appear to have suffered depletion 

 any more than others with a stream-type of fish. 



That the stay of sockeyes in fresh water appears to be a matter of 

 choice, received some confirmation last year through an experiment 

 at Grace Lake, a small barren body of water at the headwaters of 

 Morris Creek, near here. About one hundred thousand fry were 

 planted in that lake in April, 1920, and during July and August of 

 the same year, the majority of the fingerlings left voluntarily for the 

 sea when they had attained a length of three inches. These fish were 

 not over six months old and the result of an abundance of natural 

 food, coupled with freedom from molestation, is plainly evident in the 

 fine appearance of the fish. Though conditions were seemingly ideal 

 for a lengthier stay in the lake the fish left of their own accord, thus 

 strengthening the presumption that size is probably a determining 

 factor in the migration of the sockeye. At that time it was sup- 

 posed that all the fingerlings had left, but this year several thousand 

 fingerlings came down, our attention being first attracted by their 

 appearance in the settling tank of a small hatchery installed below 

 the lake. Fry planted at the same time in Otter Lake in an adjoining 

 barren body of water all left the first summer, slightly smaller than 

 those from Grace Lake, probably owing to the water being colder. 



^This paper was accompanied by a number of interesting specimens of young salmon. 



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