Fish occupy the highest levels of aquatic food webs and are both directly and indirectly affected by physical and chemical changes in the environment. The Biological Assessment Branch employs a standard method for assessing the biological integrity of wadeable streams in North Carolina by examining the structure and health of fresh water fish communities. The NCIBI is currently applicable to streams in the lower gradient portions of the Western and Northern Mountains (French Broad, Hiwassee, Little Tennessee, New, and Watauga River basins), the Inner Piedmont, Foothills, and Eastern Mountains (Broad, Catawba, Savannah, and Yadkin River basins), the Outer Piedmont (Cape Fear, Neuse, Roanoke, and Tar River basins), and the Sandhills (Cape Fear, Lumber, and Yadkin basins).

Fish community collection sites are typically located at bridge crossings or other public access points on second, third, and fourth order streams where backpack electrofishing methods can be safely and efficiently applied. Physical and chemical water quality parameters and physical habitat assessments supplement all fish community sampling events. Since 1990, approximately 960 fish community sites have been monitored across the state.

NCDWR Wadeable Streams Fish Community Assessments (Click map to expand).