Landscape Characteristics and Anthropogenic Stressors Influencing the Presence of Brook Trout and Smallmouth Bass in the Driftless Area

Downstream Strategies was contracted by the U.S. Fish and Wildlife Service to conduct a GIS based habitat condition assessment for the Driftless Area Restoration Effort and for five other Midwestern fish habitat partnerships. The assessment was conducted to help resource managers further understand current fish habitat conditions within the Driftless Area of the Upper Mississippi River basin and the natural landscape characteristics and anthropogenic stressors influencing the presence of five fish species at the 1:100k catchment scale. Assessments were completed for brook trout, smallmouth bass, longnose dace, brown trout and Cottus spp.. Results from the brook trout and smallmouth bass assessments will be discussed. The top five natural landscape variables and anthropogenic stressors influencing the brook trout and smallmouth bass models were similar and included mean annual air temperature, network percent forest cover, mean annual precipitation, network density of cattle and network drainage area. The aforementioned variables explained 42% of the total influence in the brook trout model and over 68% in the smallmouth bass model. Predicted probability of presence for both species will be summarized for the Driftless Area with potential priority watersheds identified for protection and restoration.