Roanoke logperch  (Percina rex)

Classified as Vulnerable (VU) on the IUCN Red List (1).

The Roanoke logperch belongs to a group of fishes known as darters, perch-like fish named for their habit of swimming in short, rapid bursts (3) (4). The scientific name for this species ‘rex’ means ‘king’ in Latin, a fitting name for this large and impressive darter (3). The Roanoke logperch is mainly yellowish-green in colour, except for dark blotches running along the side and the white underside. A striking orange band runs across the first dorsal fin, a feature which is particularly vivid in mature males (2).

The Roanoke logperch occurs in Virginia, USA, where it occurs in both the Roanoke and Chowan watersheds (5). A single specimen has also been found in North Carolina (2).

The Roanoke logperch inhabits clean rivers with low levels of silt. Adults typically occur in slow-moving, sandy pools as well as fast-moving gravel riffles (2), while juveniles inhabit runs and pools with clean sandy beds (6).

Much is still to be learnt about the biology of the enigmatic Roanoke logperch. It is known that this species matures at two to three years old and lives for around six years (2). It is thought to spawn around April and May, burying the eggs in gravel and ceasing any parental care thereafter (2) (5).

Logperch have prominent snouts which are used to flip over small stones to feed on invertebrates on the river bed. Due to this unusual feeding behaviour, the Roanoke logperch is thought to be intolerant of heavily silted areas, where stones become partly buried in the river bed (7).

A decline in Roanoke logperch populations is believed to have been caused, at least in part, by increased siltation of rivers due to human development (8). Water pollution caused by fine silt from urban and agricultural areas, as well as the occasional chemical spill, threatens Roanoke logperch populations (9). Populations have also become segregated due to the creation of dams (2), reducing the exchange of genetic material between populations and threatening the future viability of the Roanoke logperch (10). Any increase in the human population in the Roanoke River basin will pose an additional threat to the Roanoke logperch, due to the corresponding increase in water extraction from the basin (6).

In 1989 the Roanoke logperch was listed as Endangered under the U.S. Endangered Species Act, and in 1992 the U.S. Fish and Wildlife Service set up the Roanoke Logperch Recovery Plan (11). The recovery plan was updated in 2007 to include recommendations that focus on stream restoration and an improvement of agricultural practices in order to reduce siltation in the Roanoke basin (9).

In addition, increasing the connectivity of populations and suitable habitats for Roanoke logperch may aid their recovery by increasing exchange of genetic material (5) (8), and therefore it has been advised that some manmade barriers should be removed to aid Roanoke logperch movement between habitats (9). Continued monitoring of the Roanoke logperch and a reduction in the risk of toxic chemical spills is also needed to aid this species’ recovery (5).

View information on this species at the UNEP World Conservation Monitoring Centre.

To learn more about the Roanoke logperch see:

• U.S. Fish and Wildlife Service:
  http://ecos.fws.gov/speciesProfile/profile/speciesProfile.action?spcode=E01G