REARIXG SOCKEYE SALMON 107 



SESSIONAL PAPER No. 38a 



the color of the flesh of the fish as well. The complete fresh water life, as far as these 

 experiments show, causes no delay in the approach of the spawning perin(^. 



In only one of these cases was the later life of the fish followed up and reported 

 upon. This fish survived two spawning periods and lived to be 64 years old. There 

 is thus nothing to indicate that its life was shortened in the continued existence in 

 fresh water, nor can it be said definitely that it was prolonged. 



Eegan contends that there is no structural difference between the sea trout and 

 the brown trout, but the difference in general appearance is due to the length of time 

 spent in fresh water. That is to say, he is of the opinion that the brown trout is 

 simply a sea trout that has given up migrating to the sea. Lamond apparently is of 

 much the same opinion. If this contention is correct, and it is backed up by many 

 convincing arguments, the continued life in fresh water must have a physiological 

 effect if not a morphological, different to that when migration to the sea takes place, 

 because the brown trout is so different in general appearance, when grown, that 

 it is usually considered a different species or it might even be said many different 

 si)ecies, where local conditions produce an appearance, different from the typical. 



An experiment with the sockeye salmon, Oncorhynchus nerka, which is being 

 carried on at the hatchery at New Westminster, B.C., by Hatchery Officer H. W. 

 Doak, under the jurisdiction of Lieut.-Col. F. H. Cunningham, Chief Inspector of 

 Fisheries for British Columbia, may be of greater interest than any of these. Already 

 it is of sufficient importance to be worth recording. 



In the fall of 1912 some sockeye eggs were taken from Harrison lake to the Bon 

 Accord hatchery, where they hatched out in the spring of 1913. The fry were put 

 into rearing ponds near the hatchery, but later, when the hatchery was moved over 

 to Queen's Park, New Westminster, on account of Canadian Northern Railway opera- 

 tions, the fish were removed to ponds on the new site, where some of them still live 

 and thrive. 



In the fall of 1915 some of the males, then in their third year, became ripe and 

 the milt was removed. The spent fish mended perfectly and continued to live and 

 grow. As none of the spawning fish were marked, it was not possible to tell if those 

 spawned again in 1916, but certainly some of the males spawned in that year. None 

 of the females showed any signs of developing a spawning condition in the third 

 year, i.e., in 1915, but they did so the following year. When they were ripe the eggs 

 were removed, artificially mixed with milt for fertilization, and put in the hatchery, 

 but although they remained fresh for a long period, none of them hatched out. The 

 rest of the eggs were spawned naturally in the gravel at the bottom of the pond, but 

 apparently they were not fertilized, as none of them hatched out either. The eggs 

 were 6 to 5-5 mm. in diameter, somewhat smaller than even the smallest of normal 

 sockeye eggs. 



The spawning occurred about November 1, and on the 29th of January following 

 a number of these fish were examined. There were nine of them altogether, running 

 from 9 to 11 inches in length (not including caudal fin rays). They were not weighed, 

 but probably none of them would weigh over a pound, and some of them not that 

 much. The fish that had quit feeding during the spawning period, were taking food 

 quite readily again and appeared to be perfectly mended. The skin was bright and 

 metallic and the scales were shed quite readily. 



Scales from four of them were taken for examination. Although there is much 

 sameness in the rate of growth indicated throughout, it is possible in almost every 

 perfect scale to make out the winter check somewhat readily. The growth is not 

 quite regular even during the active part of the year, the irregularity is most notice- 

 able in the second year's growth, but it is probably on account of the general slow 

 growth that it is more noticeable in these than in normal scales. There may have 

 been some disturbing influences in connection with their life in ponds as small as 

 those in which they were kept. 



