Taste 7.— Summer foods of P. maculata at Vandalia and 
Carlyle. “Frequency” is the percent of stomachs examined con- 
taining the item listed. ‘Average number” is the average num- 
ber of items found in stomachs which contained that item. 
| << VDlStlb 
Vandalia Carlyle 
Young Adult Young 
(14) (2) (6) 
Av. Av. Av. 
Freq: No. Freq. No. Freq: No. 
San nee 
Diptera 
Chironomidae 3229 5,0 TORU te ~ ORY OGRE 
Simuliidae eorOmmON Or 100.0. 67.5 165775 120 
Diptera pupae ie. O 
Ceratopogonidae 7.1 3.0 
Ephemeroptera 
Baetidae 78.6 8.2 100.0 43.5 165781320 
Heptageniidae ae DE i oe 1627 1,0 
Caenidae foie 3.0 
[richoptera 
Hydropsychidae 64.3 1.7 000127059 100,08 6-2 
“Case builders” feel Oy D050 52.0 
crustacea 
Copepoda 23 Be ss, ae 33,0 lOe2 
Cladocera a: * a a, 16.7 4.0 
‘ish eggs ay - ae 16,7 2.0 
sand grains a ae oe et 800 Ba) 
lant materials 75) 65.0 50.0 16.0 
es ——S—S 
TABLE 8.— Comparison of summer foods of P. phoxocephala from four localities from the upper to the lower river. 
juency” is the percent of stomachs containing the item listed. 
tomachs which contained that item. 
11 
to determine times of feeding. At night (2:00 am), 
the stomachs and intestines of P. maculata and P. 
caprodes were empty, indicating that a number of 
hours had elapsed since those fish had fed. P. maculata 
collected at 7:30 pm had an average of 18 relatively 
fresh organisms in their stomachs, indicating that they 
had fed until darkness. P. phoxocephala collected at 
2:00 am still had a few heads of food organisms in 
their stomachs, and most of the intestines contained 
food, indicating that they may have fed at least for a 
while after dark. This was also borne out by a col- 
lection made on October 10, 1966, at 8:45 pm (a little 
more than 2 hours after dark). P. phoxocephala stom- 
achs contained food while most P. maculata stomachs 
were empty or had just a few organisms in the posterior 
portions of the stomachs. 
At all times feeding intensity was lower for P. 
phoxocephala than for the other Percina. The apparent 
extended feeding period of P. phoxocephala might com- 
pensate for this, 
Food Selection 
Turner (1921) believed that food preference was 
not a factor in the distribution, except locally, of Ohio 
darters. Pearse (1918) stated, however, that most fishes 
selected specific items from the available food supply 
and this might affect distribution. In a comprehensive 
study, Ivlev (1955, tr. 1961) stated that for the survival 
“Fre- 
“Average number” is the average number of items found in 
g § am 
I 
Sullivan Vandalia Carlyle New Athens-Evansville 
Young Adult Young Adult Young Adult Young Adult 
(11) (27) (10) (10) (12) (20) (9) (4) 
Ay. Av. Ay. Av. Av. Av. Ay. Av. 
Freq. No. Freq. No. Freq. No. Freq. No. Freq. No. Freq. No. Freq. No. Freq. No 
Viptera 
Chironomidae 100.0 5.2 44.4 2.4 90.0 7.8 30.0 1.7 83.3 Pome O00 2: 2m oo. o me O.Oat 00.0420 
Simuliidae poise .0 81825 .5,2 30.0 1.7 390.0 1.0 329 a0) nce ee NSM ES) 
Diptera pupae TES Vos NORD IEG) S25 2320 I Uti SSE Gh) 
_ Ephydridae Meta WES Th 6 
Rhagionidae 8.3 1.0 
phemeroptera 
_ Baetidae 36.4 3.3 29.6 2.4 100.0 5.1 60.0 4.3 50.0 2.0 2070 eo: GGT /a1 25) eee Ome) 
Heptageniidae poe 0 oe 20,9 1nd 40091, 35 8000 81 4417 1.0 AO LOS 71 e228? ae) 
_Caenidae eee teen! Ie eT Ose] OL 082.0) heh alae et 
Ephemeridae eee 7245,11.0 Bes mal Ono. 0mnl 20 
Miscellaneous J21m 2,014.8. 1.0 
richoptera 
Hydropsychidae Seeemet 0g tt. 45 473700098 100107860 500083.8 100.0 7.2 88.9 6.4 100.0 18.0 
_ Case builders” 1 ES rh a poet tens 258186 he AM: elie os 
ish eggs Sues 180 tno coer oe Pe os 22,00 5.0120 899.98 125 a es 
sect eggs a Sy prone ee Ae ee a er 5.0 10.0 eee oh ae wi, 
and grains 18,25 2.0 meee epee. SOR) es Geli 0 mee30. Ome 2 ae 22.2 1 Oe 2520 1270 
lant material ee hale a legate on me ees iar, Oe ae 
ollembola Pe be er Ee: ener! ew. ne 2 80) cone 
Pmpty) ie 14.8 ¥ - 16.7 os Rs e, 
