The goal of this study was to determine the degree to which fish species richness in a stream reach is dependent on the condition of the upland landscape versus its location along the river network. I sampled reaches on 33 tributaries to the mainstem of the Upper Coosa River basin, Georgia. Species richness at each site was estimated for all species and three different sub-assemblages based on the richness observed in spatially and temporally replicated sampling. The relative importance of major landscape-level variables, local reach-level variables, and downstream riverscape variables for predicting assemblage species richness was calculated by developing and ranking competing multiple linear regression models. Richness of all but the lotic-lentic generalist assemblage was best predicted by drainage area and conductivity. I found little evidence that downstream factors influenced local fish species richness.
