FISH ASSEMBLAGES OF THE CENTRAL APPALACHIAN MOUNTAINS - AN EXAMINATION OF TROPHIC GROUP ABUNDANCE IN 9 WEST-VIRGINIA STREAMS

We used multivariate ordination techniques to examine patterns of trophic group abundance among fish assemblages in nine West Virginia streams. These patterns were examined in relation to habitat and water chemistry gradients. The first two components from a principal components analysis (PCA) explained 71 % of the variation in trophic group abundance. The first two axes from a PCA of habitat data accounted for 75 % of the total variation. Generalized insectivores and insectivore-piscivores were the predominant trophic groups in stable, pool environments. Benthic insectivores and herbivores-detritivores were most abundant in shallow, temporally variable environments. We attributed the presence of generalized insectivores in deep, pool environments to the effects of a severe drought. The predominance of benthic insectivores in shallow environments was attributed to an abundance of benthic stream fishes and a depauperate catostomid assemblage.