Percina sciera belongs to the family Percidae, which along with Etheostomatinae comprise approximately 20-percent of the recognized diversity in North American freshwater fish.
[4] Percina prefer low water velocity in riffle/pool transition areas primarily on top of woody debris in a sandy/boulder substrate.
[6] P. sciera is found in the eastern United States in areas ranging from the Tennessee Tombigbee waterway,[7] to the unglaciated Allegheny Plateau section of Southern Ohio,[8] to the second and fourth order streams within the Pine Hills of the Mississippi coastal plain.
[5] Percina sciera microhabitats range from shallow riffles to deep runs and slow pools, with a wide variety of substrates from large boulders to mixtures of sand and gravel.
[6] In the Elk River, West Virginia, P. sciera inhabit microhabitats with a low water velocity in the riffle/pool transition areas (mean flow rate of 5.0 cubic centimeters per second at a mean depth of 45.4 cm) primarily on top of small woody debris and sand/boulder substrates, a water velocity typically slower than for Etheostoma.
[9] Adult dusky darters prey on ephemeropteran, plecopteran and odonate nymphs, as well as trichopteran and dipteran larvae.
[10] Watersnake predation is a frequent, but relatively poorly known, source of mortality for darters belonging to both Etheostoma and Percina.
[12][15] The biggest threat to P. sciera involves in-stream physical habitat alterations influenced by human activities, including non-forested land use (agriculture, residential and industrial development), effluent discharge, and water withdrawal.
[16] These human activities in the watershed alter stream morphology and increase sediment buildup and temperature, which disrupt the substrate composition in the streambed and can lead to reduced feeding, growth, and reproductive success for P.
[16] Another important stressor is the mixture of roadway surface contaminants that may be toxic to endemic darters and other stream fishes.
[11] For most stream-dwelling fishes, altered stream flood hydrology from increased stormflow runoff is a major source of disturbance.
[17] While some flooding is natural, both the frequency and severity of damage may be exacerbated in areas with numerous impervious surfaces (roadways, parking lots, etc.).
A network of pipes, wells, and collection trays (which contain gravel for larvae) has been used as a rearing and spawning area, the photoperiod breeding requirements of darters mimicked with controlled ambient light timer settings, and temperature and pH kept similar to those in the wild.
[11] P. sciera sampling sites are determined by identifying areas that fit the geomorphology of the species, looking for suitable gradient, substrate, flow and sediment transport, depth, and width.
Electroshocking provides one of the best alternatives for obtaining abundance estimates for small nongame fishes, which are not well-suited to mark-recapture techniques.
[13] When searching for P. sciera, snorkelers, who should never be in the water while electrofishing is underway, begin at the downstream end of the site and slowly proceeded upstream in a random zig-zag direction to observe as much area as possible in expansive shoals, riffles, and runs.