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 trop hic group abundance among fish assemblages in nine West Virginia strea ms. These patterns were examined in relation to habitat and water chem istry gradients. The first two components from a principal components analysis (PCA) explained 71 % of the variation in trophic group abunda nce. The first two axes from a PCA of habitat data accounted for 75 % of the total variation. Generalized insectivores and insectivore-pisci vores 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 presen ce of generalized insectivores in deep, pool environments to the effec ts of a severe drought. The predominance of benthic insectivores in sh allow environments was attributed to an abundance of benthic stream fi shes and a depauperate catostomid assemblage.