SOME NOTES ON FISH FOOD IN THE LAKES OF 

 THE SIERRAS. 



BY H. B. AVARD. 



During the month of June of this year I had the })rivileg"e of 

 spending some time at Glen Alpine Springs, California, which is 

 located in the Sierras, close to a series of lakes of considerahle 

 altitude. A cursory biological examination of these lakes dis- 

 closed biological conditions which may be of considerable inter- 

 est to members of this Society. Wliat may have been the early 

 condition of the lakes, I do not know. l)ut from the precipitour? 

 character of outlets and tlie long stretches intervening between 

 them and other waters, togetlier with the limited .amount of out- 

 flow, it seems impossible for fish to gain a footing. From time 

 to time, however, within recent years, plants of trout have been 

 made in these lakes with varying degrees of success. There ar."" 

 consequently two questions which will come at once to the minds 

 of all members of the Society ; first, what is the source and char- 

 acter of the food on wliicb these forms have subsisted? Second, 

 how far have they adapted themselves to their environment in 

 the process of l)ecoming a ])ennanent ])art of it? Although 

 the study could not be extensive in the time at my disposal, even 

 a brief survey disclosed some features of fonsideral)le interest, 

 wliicli 1 desire to present in tentative form at this time. 



A few words regarding the lakes tbemselves may not be out 

 of place, '^rhey are all located ueai' the southeast corner of Lake 

 Tahoe, and empty theii- waters nltinuitely into that lake, through 

 the medium of a smallci' body known as Fallen Tjcaf I^aki' ; the 

 latter is located directly soutb of tlu' main lake, and separated 

 from it only by a low alluvial plain not (juite two 

 miles in width, so that one may regard this smaller 

 lake as but a branch of the larger one. I^'ollowinu' the 

 inlet of Fallen Leaf Lake, upward and away from tliis 

 body of water, the vall(3y ascends very rapidly and the 

 channel of the brook is little more than a succession of rapids 

 and falls, in some eases of considerable height. The amount of 

 water in it during the early ])art of the vear, while the snows of 



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