100 American Fisheries Society 



had been carried on for fifty, seventy-five or a hundred 

 years with no apparent reduction in the number of the 

 fish. Finally, however, they became so scarce that when 

 I was up there in 1901 we had a man on those brooks 

 night and day and failed to secure a single fish and none 

 was seen in any of their former spawing places. We did 

 manage to secure one fish, in Kennebago stream, weigh- 

 ing about three-quarters of a pound, which was much 

 larger than usual. I got several others in 1903 and 1904, 

 all large fish. Subsequently they appear to have become 

 extinct. The few that remained prior to their disappear- 

 ance increased in size. The cause of the extinction, I 

 believe, was the "successful" introduction of the land- 

 locked salmon, which, with the common trout, subsisted 

 to a great extent upon the little blue-backs. The blue- 

 backs disappeared down the maws of the salmon as it 

 were. It was not until 1891 that other food was afforded 

 them by the introduction of the smelt, which was too 

 late. 



The later phenomenal increase in size of the blue-back 

 was probably attributable to the smelt, in the young of 

 which it found an increased and unaccustomed abundant 

 food supply, as the young smelt apparently go into deep 

 water while almost in a larval state. 



The pictures following those of the blue-back are of 

 the famous golden trout, or Salvelinus aureolus of Suna- 

 pee lake (demonstration). It was not described until 

 1887. It is closely related to the blue-back, and it is 

 difficult to distinguish the preserved dead specimens 

 of this fish from blue-backs of the same size under 

 the same conditions. In fact, it was believed by many 

 to have appeared in Sunapee lake as the result of the in- 

 troduction of blue-backs. Some, however, maintained 

 that it was the introduced Europen saibling. Those who 

 advocated the blue-back theory would have been delighted 

 had they foreseen the increase in size of that fish in 

 Rangeley lake, as the principal argument of the oppon- 

 ents of the theory was that the Rangeley blue-back was 

 always a much smaller fish. Regarding this fish, I have 



