Amber Darter

Percina antesella

Description

The amber darter, Percina antesella, is a short, slender-bodied fish generally less than 2.5 in (6 cm) long. The upper body is golden brown with dark saddle-markings; its belly is yellow-to-cream in color, and the throat of a breeding male is blue.

Behavior

In late winter or early spring, the amber darter swims up small streams to spawn in shallow marshy areas. It feeds primarily on gastropods (snails and limpets) and aquatic insects and larvae of caddisflies, mayflies, midges, beetles, and stone-flies. They also feed on fish eggs.

Habitat

The amber darter only inhabits areas of gentle riffles over sand and gravel bottoms. The species has not been observed in slack current in areas with debris or a mud bottom. As summer progresses, the amber darter uses the profuse vegetation that grows in the riffles for feeding and cover.

Distribution

A study completed in October 1983 concluded that the amber darter was restricted to the upper Conasauga River basin (a tributary of the Coosa River) in Georgia and Tennessee, with the exception of a small population in the Etowah River in Cherokee County, Georgia. The amber darter's preference for gentle riffles may explain why the species has not been found above the U.S. Highway 411 crossing in Polk County, Tennessee, where the Conasauga River's gradient steepens. Downstream, the amber darter's range is probably limited by heavy siltation.

As recently as 1982 and 1983, biologists could not find the amber darter in the Etowah River. If there is still a population in this river, it is very small. The only other collection record for the amber darter was from Shoal Creek, a tributary to the Etowah River (Cherokee County), Georgia, where the fish is no longer found. The Shoal Creek amber darter population was probably destroyed in the 1950s when Allatoona Reservoir inundated the lower portion of Shoal Creek.

The amber darter is now found along 33 mi (53 km) of the Conasauga River from the U.S. Highway 411 bridge near the town of Conasauga, Tennessee, downstream to the Tibbs Bridge in Murray County, Georgia. This stretch of the Conasauga River passes along the southern edge of Polk and Bradley counties, Tennessee, and curves south through Murray and Whitfield counties, Georgia. There is no current population estimate.

Threats

The amber darter is threatened by runoff from agricultural and urban development in portions of the watershed. Because of its limited distribution, the amber darter could be jeopardized by a single catastrophic event. Heavy truck traffic across river bridges poses the threat of a toxic chemical spill that could eliminate a large percentage of the population. Increased tree farming activities, road and bridge construction, stream channel modifications, impoundments, changes in land use, and other projects in the watershed could have adverse impacts.

The impoundment of the Etowah River at Alatoona Reservoir has caused a great reduction of the population size in the Etowah River. Stream flow, water temperature, and siltation were all modified, especially during construction. And because of its limited distribution, the amber darter's ability to move to other suitable habitat was restricted by the impoundment's turbulent water.

The Etowah River system is subject to disturbance from potential changes in land use and activity, including silverculture, road and transmission lines maintenance, and pollution by herbicide and pesticide use.

Conservation and Recovery

The upper Conasauga River flows through the Chattahoochee and Cherokee national forests, and this undisturbed flow provides partial protection for the amber darter's downstream habitat. Further water control projects in the drainage require consultation with the U. S. Fish and Wildlife Service under provisions of the Endangered Species Act.

Contact

Regional Office of Endangered Species
U.S. Fish and Wildlife Service
1875 Century Blvd., Suite 200
Atlanta, Georgia 30345
http://southeast.fws.gov/

References

Etnier, D. A., B. H. Bauer, and A. G. Haines. 1981."Fishes of the Gulf Coastal Drainage of North Georgia." Unpublished Report. U.S. Fish and Wildlife Service, Atlanta.

Freeman, B. J. 1983. "Final Report on the Status of the Trispot Darter and the Amber Darter in the Upper Coosa River System in Alabama, Georgia, and Tennessee." Report, Contract No. 14-16-0004-48. U.S. Fish and Wildlife Service, Atlanta.

Starnes, W. C., and D. A. Etnier. 1980. "Fishes." InD. C. Eagar and R. M. Hatcher, eds., Tennessee's Rare Wildlife; Vol. 1, The Vertebrates. Tennessee Heritage Program, Knoxville.