Resource Use by Two Sympatric Black Basses in Impounded and Riverine Sections of the New River, Virginia

Abstract
Smallmouth bass Micropterus dolomieu and spotted bass M. punctulatus are sympatric in riverine and impounded sections of the New River, Virginia. Resource use (habitat and food) by the two species was investigated to determine patterns and extent of resource partitioning and how those patterns might differ between lotic and lentic environments. Growth and body condition were also measured to assess performance of populations of the two species in the study areas. Diet analyses showed that similar prey were consumed by the two species. Habitat use differed along a lotic–lentic gradient; spotted bass were predominant in the impoundment, and smallmouth bass were more abundant in the river. Spatial segregation also occurred within river and impoundment habitats. In the impoundment, smallmouth bass were concentrated in areas with steep dropoffs and rocky substrates, and in the river, they used shoreline areas more than midriver areas. Spotted bass were widely distributed in the impoundment but were mo...