Food Use in Minnesota Populations of the Topeka Shiner (Notropis topeka).

We examined gut contents of 65 Topeka shiners (Notropis topeka) collected from the Rock River drainage of southwestern Minnesota in 1997. Anecdotal and unpublished information regarding food habits have suggested that the Topeka shiner is largely a benthic or nektonic insectivore. Our results show that it is an omnivore that feeds opportunistically on immature aquatic insects, several kinds of microcrustaceans and other invertebrates, larval fish, algae, vascular plant matter, and detritus. The Topeka shiner functions both as a benthic and nektonic feeder and shows strong trophic similarities to its sister species, the sand shiner (N. ludibundis). [ABSTRACT FROM AUTHOR]