摘要：Fish were collected from typical channel habitat within five pools of the Allegheny River navigation system in 2007-2008 by benthic trawling in the river channel and shoreline boat night electrofishing. Trawling collected 5,914 fishes of 32 taxa; electrofishing collected 3,418 individuals of 55 taxa. Numerous species offish associated with great river assemblages and once extirpated from the waters of Pennsylvania were well represented, as were some species which until recently were considered to be threatened, endangered, or candidate species in Pennsylvania. The biomass of the navigation system is now dominated by native catostomids, especially silver redhorse (Moxostoma anisurum) and smallmouth buffalo (Ictiobus bubalus). Trawling very effectively sampled the family Percidae, with the average percentage of composition being 59.5%, whereas only 12.2% of the electrofishing catch was percids. Backpack electrofishing at the mouths of 18 tributaries added 10 additional taxa, for a total of 73 species/hybrids. In terms of species richness, these results were nearly identical to those of an extensive recent evaluation of the nearby Monongahela River in Pennsylvania.
