Fishes of the Missouri National Recreational River, South Dakota and Nebraska

摘要

Two sections of the Missouri River, one extending 94 km downstream from Gavins Point Dam, and the other extending 62 km downstream from Fort Randall Dam, are legally designated as National Recreational Rivers. An ichthyofaunal list and fish habitat data were needed for conservation planning by states and federal agencies (e.g., National Park Service). We collected fish during three summers from four macrohabitats, using five fish collection techniques, and measured fish habitat characteristics. Temperature, conductivity, and turbidity varied little, but substrate, depth, and velocity differed among macrohabitats (e.g., depth and velocity in the channel exceeded those elsewhere; sand dominated the substrate except in silt-laden tributary mouths and backwaters). We collected 21,699 fish of 53 species and combined our survey with others to compile a list of 92 species. Common recreational species included walleye (Sander vitreum) and catfishes (Ictaluridae). Twenty nonnative species were present. Seventy-two native species have persisted, but the pallid sturgeon (Scaphirhynchus albus) is endangered and a few other species (e.g., native minnows) may be in decline.