Warmwater Stream Assessment Evaluation

            Throughout North America, there has been an extensive decline in the distribution of native fishes (Williams 1989).  As a result, warmwater stream systems and the native fishes within them have come under closer scrutiny.  The Wyoming Game and Fish Department (WGFD) is responsible for conserving and enhancing game and non-game fishes and habitat within Wyoming both in warmwater and coldwater systems.  Therefore, a method to assess warmwater systems in Wyoming that could be used by WGFD was needed.  Several warmwater assessment methods have been used in other areas but a need existed for a method that was tailored to management needs, incorporated fish and habitat information, and provided some insight as to how fish assemblages have changed through time and the possible reasons for such change.  Therefore, the Warmwater Stream Assessment (WSA) method was developed to meet these needs. 

            The WSA entails the collection of both fish and habitat information from selected reaches within prairie streams.  Habitat information collected includes habitat type (pool, riffle, run, backwater, side channel), substrate type (silt, sand, gravel, cobble, boulder, bedrock) and percent embedded, cover type (aquatic vegetation, woody debris, overhanging cover, undercut bank), length, wetted width, and depth of habitat units, as well as classification of turbidity, intermittency, and influence of anthropogenic activities on the reach.  Information on fish within each reach is obtained by electrofishing or seining.  All fish are identified to species and counted to obtain fish presence and abundance within each reach.

                  During 2004 and 2005, 104 WSA surveys were conducted throughout eastern Wyoming.  Information obtained during these surveys will be used to evaluate and critique the WSA as a method for assessing prairie stream systems in Wyoming.  The result will be a method for WGFD to use in continued monitoring of warmwater stream systems through the state.