Influence of Prey Type on Growth of Young Yellow Perch (Perca flavescens)

Growth of age 0 + yellow perch (Perca flavescens) fed different zooplankton diets was examined in the laboratory during June and July 1983. Fish were fed an equal mass of diet types that varied with respect to prey species, mean length of the same prey species, and species mixture. Fish consumed all prey within 4 h of feeding. In four trials the ranking of diet type by fish growth was always Diaptomus sicilis > Oneida Lake tow sample > Daphnia spp. Differences in fish growth frequently varied by 50–300%. These differences suggest that nutritional processes, such as digestion or assimilation, will influence the optimal prey selection for, at least, small zooplanktivorous fish.