38 Food of Fishes of Winona Lake 



The food found for this species compares very favorably with that found 

 by S. A. Forbes ('80), who, in examining specimens of Lepomis pallidus 

 Mitchill, found that those measuring three-quarters to one inch contained 

 fifty-seven per cent entomostraca, thirty-seven per cent chironomus larvae and 

 six per cent water spiders and amphipods. For those measuring two to three 

 inches he found the food to consist of eight per cent neuroptera and eighty- 

 one per cent Chironomus larvae and entomostraca. For the adult he found 

 the food to be neuropterus insects, caddis-fly larvae, dragon-fly larvae, vegeta- 

 tion, mollusks, a small fish, Planorbis, Physa, Amnicola and Vivipara. 



Micropterus salmoides Lacepede (Large Mouth- Black Bass) — Table III 



The large mouth black bass is a very abundant fish in Winona Lake. 

 The small bass keep very close in shore and may be taken at almost any 

 location around the lake where there is a protected spot and vegetation of 

 any kind. The larger bass are found farther out, lying at the edge of 

 dense growths of Potamogeton and spatterdock. 



By examining Table III, two changes in the kind of the food used may 

 be seen to occur. Small bass measuring from 24 mm. to a length near 38 

 or 40 mm. were found to feed mostly on small crustaceans, chiefly amphipods 

 and cladocerans, ephemerida larvae and pupae and Chironomus larvae. Six 

 had eaten a small amount of fish and three had taken a small amount of 

 algae. With an increase in size, the bass utilizes a larger number of foods 

 until a length of approximately 50 mm. is reached, when the variety decidedly 

 decreases and we find the fish depending principally on the small fish of the 

 lake for food supply. From approximately 39 or 40 mm. lengths to about 

 50 mm. lengths, the principal foods are still small crustaceae, ephemerida 

 larvae and pupae, and Chironomus larvae with an increase in the number 

 eating fish and insects. Of the 62 bass measuring more than 48 mm. in 

 length we find that 47 of them had taken fish as the chief food. Also, of 

 the 62 examined, only two of them had taken small crustaceae and very few 

 had eaten insects or insect larvae. The bass ate about the same food through- 

 out the entire summer. 



Incidentally we may note the inroads of the parasitic trematodes upon 

 the bass. Of the 133 black bass examined 32 were infected by the trematode, 

 Leuceruthrus micropteri or about 25 per cent of the entire number. 



The food of the large mouth black bass of Winona Lake corresponds 

 very closely with the food found in the stomachs of black bass examined by 

 S. A. Forbes ('80). Forbes found the food of the young to consist chiefly 

 of entomostraca, principally cladocera, minute fishes and insects. In the 

 adult he found a total disappearance of entomostraca, and an accidental oc- 

 currence of insects. The main food was fishes, 86 per cent, with 7 per cent 

 cray-fish. 



Comparing the food of the bass found at Winona Lake during the summer 

 months with that found by Hankinson ('07), at Walnut Lake from April 

 1 1 to June 10, we find a great difference. Hankinson found on examination 

 of 24 large mouth black bass, all ate cray-fish, 5 ate fish, 1 ate 350 midge 

 larvae and pupae besides Sialis and damsel-fly larvae, cray-fish apparently 

 being the most important food. This difference may be due to the different 

 seasons during which the examinations were made or due to different environ- 

 ments. 



