Diet Overlap of Introduced Rainbow Trout and Three Native Fishes in an Ozark Stream
Daniel B. Fenner, Maureen G. Walsh, and Dana L. Winkelman
Abstract.—Private angling groups in Oklahoma have requested permission to stock rainbow trout Oncorhynchus mykiss into streams of northeastern Oklahoma although little is known regarding interactions between introduced rainbow trout and native fishes in these systems. Our study objectives were to assess diet overlap between introduced rainbow trout and native smallmouth bass Micropterus dolomieu, shadow bass Ambloplites ariommus, and bluegill sunfish Lepomis macrochirus in Brush Creek, Oklahoma, a small spring-fed Ozark stream. Rainbow trout diet composition differed from that of all three native fishes in the 2 months of comparison (March and May 2001), and rainbow trout diets contained relatively low numbers of prey. It is unlikely that exploitative competition for food resources occurred between rainbow trout and these three native fishes.