Effects of Riparian Area Management on Stream Habitat and Fish Communities in Central and Southwest Wisconsin

Abstract

To better understand the effects of different riparian vegetation management strategies on physical habitat and fish communities in streams, we compared differences among stream sites having four different riparian characteristics: well-managed grazing, grass, early successional-shrub vegetation, and late successional-wooded vegetation. Study sites in 44 streams in southwest and central Wisconsin were selected and paired with upstream covariate stations. Habitat was quantified using transect methods while fish were sampled using electrofishing. Results indicate that there were few differences in stream habitat and fish community characteristics among the four riparian treatment types. Only percent erosion was higher in wooded sites in southwest Wisconsin streams where topography is steeper. There were, however, significant relations in stream habitat features and IBI scores between the upstream covariate and treatment stations indicating that upstream watershed conditions clearly override the influence of the four site-specific riparian management strategies evaluated. While previous studies clearly show negative effects from heavily grazed riparian areas, our results indicate that a variety of well-managed corridors from well-managed grazing to wooded are equally capable of protecting stream habitat and fish communities.