Evaluation of Rainbow Trout Introduction in Northeastern Oklahoma Streams: A Conceptual Framework

Maureen G. Walsh, Daniel B. Fenner, and Dana L. Winkelman
Oklahoma Cooperative Fish and Wildlife Research Unit 404 Life Sciences West Oklahoma State University, Stillwater, OK 74078 (405) 744-6342 (405) 744-5006 danaw@okstate.edu, Contact: wmauree@okstate.edu

Recently, angling groups in Oklahoma have indicated interest in stocking rainbow trout (Oncorhynchus mykiss) into coolwater, spring fed streams of northeast Oklahoma. Possible negative impacts of trout stocking on native fish populations have prompted the Oklahoma Department of Wildlife Conservation (ODWC) to adopt a "risk free" position, denying all stocking permits pending evaluation of trout introduction in these stream ecosystems. Of particular interest are possible impacts of trout introduction on smallmouth bass (Micropterus dolomieu) populations, which support an active recreational fishery in northeast Oklahoma. Trout may compete with smallmouth bass for food and habitat, and may prey on juvenile smallmouth bass. Effects of trout stocking on native non-game fishes, invertebrates, and trophic interactions are also unknown. Project design involves characterization of fish communities, mesohabitat, and fish (particularly smallmouth bass) microhabitat use and diet in two streams for one year prior to trout introduction. Beginning fall 2000, rainbow trout will be stocked into one of the streams to evaluate changes in resource use and community structure of native fishes in the presence of trout. This presentation explores the ecological concepts and fisheries issues raised by this project, and also outlines the steps that will be taken to address specific research objectives.