Bryce E. Daniels and Guenter A. Schuster, Department of Biological Sciences, Eastern Kentucky University, Richmond, KY 40475

Abstract. An ongoing community analysis is being conducted to assess the impacts of anthropogenic factors on a freshwater mussel (Bivalvia: Unionidae) assemblage in the Licking River at Butler, Pendleton County, Kentucky. The level of recruitment (i.e., reproduction) taking place will be determined by the presence of glochidia (unionid larvae) in stream drift, glochidial encystment on the fins and gills of fish hosts, and juvenile mussels within the sampling areas. Preliminary analysis of drift net samples has yielded 18 glochidia and 102 juvenile Corbicula fluminea, the exotic Asian clam, in approximately 150-m³ of stream drift. Quantitative sampling, consisting of substrate excavation of randomly selected 0.25-m² plots, has resulted in the discovery of juveniles of five species of native mussels, including three juveniles of the federally endangered fanshell, Cyprogenia stegaria. Preliminary importance values were calculated for every unionid species quantitatively sampled, by taking a sum of each species' relative abundance, relative frequency, and relative volume. This method has shown the spike, Elliptio dilatata, to be the most important species occurring in the sampled areas. A combination of qualitative and quantitative searches has yielded 26 extant unionid species within the area. Anthropogenic factors in the drainage, and the presence of large numbers of C. fluminea, have had an impact on the resident mussel species. This analysis provides baseline population parameters on each species encountered that can be used in future monitoring efforts at this biologically and historically significant site.