Food habits of gizzard shad (Dorosoma cepedianum), threadfin shad (D. petenense), and blue tilapia (Tilapia aurea) were studied in summer and winter, 1975. Stomach contents of all 3 species consisted predominantly of organic detritus, followed by green algae, blue-green algae and diatoms. Occurrence of planktonic foods corresponded closely with the composition of the plankton. Although food habits differed between season, they were closely correlated among species within season. Similarities in food habits of the 3 planktivorous species suggest potential food competition.