182 Conservation Department 



Egg-eating Species. — An interesting seasonal variation in diet 

 was noted for several species. During the first three weeks of the 

 period covered by the survey many fish were spawning. As noted 

 in Table 3, the eggs formed a considerable portion of the diet of 

 several fish, especially in a sucker {Moxostoma anisurum), the 

 long-nosed dace {Rhinichfhys cataradae) ; three minnows (Notro- 

 pis volucellus, N. deliciosus, N. hudsonms) ; the log perch (Percina 

 caprodes) ; and two darters {Poecilichtkys coerideus and Cot- 

 togaster copelandi). Later in the season the diet of these fish 

 changed radically. This is shown most clearly in the case of N. 

 deliciosus. It was not possible to determine by what species the 

 eggs w^ere laid. However it seems probable that most of the eggs 

 were deposited by other small minnows and darters. 



Species Feeding Mainly on the Surface. — Four species of 

 fish are included in this group. A summary of their stomach con- 

 tents is as follows : 



Hiodon tergisns (IVIooneye) : Twenty-four specimens contained 

 food. The length varied from 10.6 cm. or 4 inches to 14.6 cm. or 

 5% inches. Cladocera, 6 per cent ; mayfly subimagoes and adults, 

 35 per cent ; midge pupae and adults, 8 per cent ; misc. terrestrial 

 insects, 51 per cent. 



Clinostomus elongaius (Red-sided dace) : Eleven fish contained 

 food. The length varied from 8.8 cm. or l^/) inches to 6.4 cm. or 

 2^2 inches. The stomach contents were made up entirely of mis- 

 cellaneous adult insects which could be found only at the surface 

 of the water. 



Semotilus afromacidatus (Horned dace). Records Avere obtained 

 for 19 fish. Lengths varied from 3.7 cm. or 1^/4 inches to 19 cm. 

 or 7^2 inches. Summary of food : Green algae, 5 per cent ; plant 

 fragments, 20 per cent ; misc. adult insects, 40 per cent ; Millipedes, 

 5 per cent ; earthworms, 30 per cent. 



Notropis umhrafilis (Blood-tailed minnow). Twelve records 

 were obtained. Lengths, 3.3 cm. or 1\^ inches to 3.9 cm. or l^/o 

 inches. One Pleuroxus denticulatus was eaten. Otherwise the 

 food was surface drift and was abnost entirely adult insects. 



The Fishing=eating Species. — Small fish are an important 

 article of diet for many of the food and game fishes of this drain- 

 age. An effort was made to determine whieh species are nu)st com- 

 monly eaten. All fish remains found in stomachs were saved and 

 were identified by i\Ir. J. R. Oreeley wlienevei- theii- condition per- 

 mitted this. Table 2 shows the results of tliis work and gives 

 a summarv of the stoniaeli eouleiils of the lish eaters. 



