Conservation status of mountain sucker in South Dakota

Luke Schultz – M.S. proposal seminar

The loss of native fishes and the homogenization of freshwater fish communities are serious global concerns that reflect human activities in the biosphere.  Actions to conserve native species begin with understanding the limiting factors to stop species loss.  Mountain sucker (Catostomus platyrhynchus) are native to the Black Hills of South Dakota and evidence indicates that recent declines may have occurred.  The objectives of this study are to (1) document the current distribution of mountain sucker in South Dakota for comparison with historic records, (2) evaluate factors influencing their distribution, (3) and assess their thermal criteria.  Electrofishing and habitat sampling at historic mountain sucker occurrence sites and upstream and downstream exploration from those sites will allow assessment of their current spatial distribution for comparison with historic distributions on multiple spatial scales.  A series of a priori predictive models has been developed to predict mountain sucker density based on a variety of factors.  A multi-model inference approach will be used to determine critical habitat, geomorphic, and biotic community variables influencing mountain suckers.  A combination of field and laboratory studies will elucidate mountain sucker thermal criteria, and allow assessment of elevated stream temperature on their future distribution.  A better understanding of native fish ecology is critical to the management and recovery of imperiled fishes and in preventing future imperilment.