50 Conservation Department 



whitefish was not a feeder on the smaller plankton Crustacea to the 

 extent it was hoped, most of its plankton food at this season con- 

 sisting of mysis and others of the larger forms. The crayfish was 

 an important food of the rock bass, black bass, eel and, to a less 

 extent, of the bullhead, pickerel and yellow perch; mollusks of the 

 sunfish and whitefish but to a much smaller extent that we ex- 

 pected of other species. The mollusks taken by the whitefish were 

 largely the small bivalves, sphaerium and pisidium. Algae and 

 plant fragments were found in several fish but were evidently 

 taken mostly by accident with their other food, except in the case 

 of the carp and golden shiner. The latter is our only predomi- 

 nantly vegetable feeder. We found that the carp* in these lakes 

 fed more extensively on larval insects and small Crustacea than we 

 had expected. However, I have found in previous years that carp 

 in Canandaigua lake range the shallows along the shale bluffs at a 

 depth of from three to ten feet in considerable numbers to feed on 

 crayfish which are the natural food of the black bass. It is signifi- 

 cant that the carp which inhabits the shallow water is a rival for 

 the food supply of the perch, bass and other valuable species. 



The lake trout in Seneca, Keuka and Cayuga lakes feed almost 

 exclusively on alewives. The trout in other lakes were evidently 

 getting an insufficient food supply as rarely did we take one whose 

 stomach was completely filled. In Owasco lake they bore conclu- 

 sive evidence of being starved. They were scarcely in edible con- 

 dition. Their bodies were light and narrow, their heads propor- 

 tionately large and their stomachs contained little but mysis. Only 

 five of the fifteen taken in Owasco had succeeded in capturing fish, 

 and only one of these had a full stomach — one cisco. It was evi- 

 dent that the cisco and smelt in Owasco were not sufficiently plen- 

 tiful to furnish the trout with adequate food and in Canandaigua 

 we feel sure that the scarcity of trout is due in large measure to the 

 scarcity of food fish on which they can subsist. 



The burbot is a gormandizer and feeds largely on small fishes. 

 One specimen contained nine fair sized perch. There can be little 

 doubt that he gathers up a large proportion of the young trout 

 and whitefish before or soon after they leave the spawning beds, 

 for he is a deep water fish and must be considered a serious enemy 

 of our better food fishes. The stomachs of burbots were almost 

 without exception partially filled with sticks, stones and other 

 debris which they gather by accident in rushing after their prey. 



A rainbow trout, taken near the surface on Seneca lake and 

 weighing 7% pounds, was filled with an enormous quantity of land 

 insects which it had evidently taken from the surface of the water, 



* See carp studies by Smallwood and Struthers, page 67. 



