10 
TABLE 6. — Seasonal foods of P. maculata at Sullivan. 
containing the item listed. “Average number” 
Se eee 
Spring Summer Fall Winter 
es . !!UlCtst—s—~S 
Young Adult Young Adult Young Adult Young 
(11) (4) (23) (20) (10) (3) (5) 
Av. Av. Ay. Av. Av. Av. Ay. 
Freq No. Freq. No. Freq. No. Freq. No. Freq No. Freq. No. Freq: aggio. 
Diptera 
Chironomidae 100 18.5 100 28.8 sree | eles 60° 17:1 1007 217.2 67 1 80a, 
Simuliidae Ola. 6 13508201, 4 4 ay 3) 30 16.3 33 10 20 
Diptera pupae Soe 2.2 Ph) 30ers 3005 253 30 yee! 20'ma 
Diptera adults bo 10)! 
Anthomyiidae 28) ee ae a 
Ceratopogonidae  ) 20° ai 
Ephemeroptera 
Baetidae aS a 5/7 e 1055 60 10.8 60°) 297 67 16 20:0 
Heptageniidae Plas Kl 300223 Sey Bia! 10 Reel 
Caenidae Soe [Omit o Re 
Miscellaneous yey 4 i 20 
Trichoptera 
Hydropsychidae Pee 1 4 15 10 50 Rone 67 3 40 Hl 
‘Case builders” ep 33 1 
Coleoptera 
Haliplidae ames 
Hemiptera 
Notonectidae 4 2 See 
Crustacea 
Copepoda 6352020 BP teat 80 84 
Cladocera 303054 Wye 40 2 
Ostracoda 18 ; 
Fish eggs ar ae he 
Insect eggs ee ve 100 l@ it nie me 
Sand grains 9° 129 20 Sse 10 a2 33 1 
Plant fragments 452 ae oa LOMees 
In a comparison of summer food habits of P. phoxo- 
cephala in four areas of the river (Table 8), baetid 
nymphs, chironomid larvae, and hydropsychid larvae 
predominated as food items. Food habits were similar 
at all four stations, although there was increased utiliza- 
tion of baetids and hydropsychids at the lower stations. 
Hydropsychids made up 80 percent of the volume of 
food in seven adults collected at Vandalia, and Le 
percent of the volume of food of six adults at Carlyle. 
Baetids made up the largest volume of food in young 
P. phoxocephala at Vandalia, demonstrating the differ- 
ence in food habits of young and adults. 
In a comparative study of the three species at Sullivan 
(Table 9), P. caprodes was found to eat the greatest 
variety of organisms and to feed on groups such as 
Plecoptera, Odonata, Coleoptera and Gastropoda that 
were rare or absent as food of other Percina. P. caprodes 
also utilized more chironomids, dipteran pupae, hep- 
tageniids, caenids, and hydropsychids than the other 
two species of Percina at Sullivan. 
Feeding habits of P. caprodes were found to change 
from a high utilization of chironomid larvae and dip- 
“Young 
those 1 year of age or older. “Frequency” is the percent of the tot 
is the average number of items found in stomachs which contained that item. 
» yvefers to fish in their first year of growth; “adult” fish are 
al number of stomachs examined (including those empty) 
teran pupae in the young, to greater utilization 
heptageniid and caenid nymphs and hydropsychid lary 
in adults. In seven stomachs from adults collected 
August of 1965, heptageniid nymphs made up an | 
erage of 73 percent of the total volume. 
Food habits of P. phoxocephala at Sullivan w 
similar to those of P. maculata; however, P. phoxe 
phala utilized more hydropsychids than P. macul 
and more simuliids than P. caprodes. 
Food organisms consumed by P. shumardi in 
lower river consisted primarily of chironomid and 
dropsychid larvae (Table 10). This darter util 
fewer baetids than did the sympatric P. phoxocepl 
but otherwise feeding habits of the two species WV 
similar. 
Time of Feeding 
Darters were found to feed throughout the dayl 
hours. When the water was warm and digestive 1 
were fast, estimates of feeding periods could be mi 
On August 17, 1966, fish were collected from the 5 
van station at five different times of the day and n 
