American Fisheries Society 205 



the surface of the pondweed zone looking for surface in- 

 sects of which grasshoppers constituted a large proportion. 

 A few of these fishes taken in late summer had many 

 grasshoppers in their stomachs. 



In early April fiooded portions of the sedge zone were 

 used by pike for breeding purposes, and large individuals 

 were sometimes found getting around in the shallow water 

 among the sedge plants with much difficulty. Gunners look 

 for them at such times and thus undoubtedly do much 

 toward diminishing the numbers of this important game 

 fish. Schools of minnows on a few occasions were seen 

 far from the lake swimming in a few inches of water 

 among the sedge plants. At the lakeward margin of a part 

 of this zone in early April just as the ice was leaving the 

 lake, many small fishes were found hidden in the submerged 

 portions of sedge tufts. These were mostly blunt-nosed 

 minnows, but a Cayuga minnow and a few Etheostoma 

 ioivce were found here. 



SUMMARY 



The results of the work at Walnut Lake that seem to be 

 of especial importance are here summarized: 



It is a type of lake fitted to support whitefish. Some of 

 the conditions there favorable for them, appear to be plenty 

 of deep water with much of it at a low temperature through- 

 out the year and abundance of food in the form of larval 

 midges in the bottom material everywhere that other con- 

 ditions are favorable for these fish. 



Midge larvae appear to be the most important articles of 

 food for the fishes in Walnut Lake. 



May-fly larvae {Hexagenia and Heptagenia) are im- 

 portant food for those sunfish with small mouths like tfie 

 bluegill and common sunfish. 



Crayfish are eaten extensively by black bass, and probably 

 form the chief food of this species in the lake. 



Minnows appear to be unimportant as food for other 

 fishes in the lake, but seem to be detrimental to the general 



