Effects of geomorphology and local habitat on fish assemblages in the Wayne National Forest

In 2006, we studied fish assemblages, geomorphology, and local habitat in 13 headwater streams within the Wayne National Forest in southern Ohio.  Stream reaches were chosen to represent future land use condition associated with the recently approved Forest Plan.  Reaches were located in two watersheds (Little Muskingum in the Marietta District and Symmes Creek in the Ironton District).  Current land use condition in each subwatershed was similar with sites dominated by forest cover (>70%).  Sites were first or second order streams with drainage areas less than 10 square km, and were generally steep, controlled by valley geometry with coarse substrate material.  Index of Biotic Integrity scores were not significantly different between watersheds.  Ordination of species data showed separation of sites between watersheds, and multi-response permutation procedure showed significant differences in fish assemblages between watersheds.  Thirteen fish species were unique to Symmes Creek, while four were unique to Little Muskingum.  Unique fish species in Symmes Creek were pool dwellers, and pools were significantly deeper than pools in Little Muskingum.  Three darter and one dace species were unique to the Little Muskingum, where the amount of cobble and current velocity were significantly greater than Symmes Creek.  Differences in fish assemblages between watersheds may relate to the amount of groundwater flow, as we found significantly greater abundance of cold-water taxa in the Little Muskingum watershed.  Results from this study will serve as baseline data to monitor effects of future land use by the Forest Service.