Smoky Madtom

Noturus baileyi

Description

The Smoky madtom, Noturus baileyi, is a small, light brown catfish with a somewhat elongated, bow-shaped body, small eyes and a rounded caudal fin. The largest known specimen was 2.9 in (7 cm) long.

Behavior

The Smoky madtom has been found in various stages of breeding condition during the spring and summer. Nests containing an average of 35 eggs have been located during July under large slab rocks in pool areas. This fish is probably nocturnal and is thought to feed on aquatic insects.

Habitat

From May to November this small catfish is generally found beneath slab rocks at either the crest or base of riffles. It utilizes silt-free riffles during other times of the year.

Distribution

The Smoky madtom was both discovered and nearly extirpated at the same time. In 1957 a U. S. Fish and Wildlife Service crew was treating Abrams Creek in the Great Smoky Mountains National Park (Blount County, Tennessee) with a fish toxicant. The purpose of the operation was to remove non-native fish from the watershed before closure of the Chilhowee Dam. Five dead Smoky madtom specimens were taken from the creek and provided the basis for its scientific description. The species was thought to be extinct until it was rediscovered in Citico Creek in the Cherokee National Forest in 1980.

The only known population of the Smoky madtom is the rediscovered population inhabiting a 6.5-mi (10.4-km) stretch of Citico Creek in Monroe County, Tennessee. The habitat is administered by the Forest Service.

Since the Smoky madtom population trend from 1990 through 1994 appeared stable to upward, cooperating conservation organizations decided to continue with attempts to restore the species to Abrams Creek in the Great Smoky Mountains National Park. Aquarium-reared fry were released each year from 1990 to 1992. Night snorkeling surveys in Abrams Creek located a few surviving Smoky madtoms in 1990 and 1991, but none were observed in 1992. No evidence of natural reproduction had been documented by 1994, but once successful spawning occurs, the likelihood of finding individual Smoky madtoms will increase greatly.

Threats

Because Citico Creek holds the only known Smoky madtom population, it is imperative to reestablish this species in another stream within its historic range.

The Smoky madtom's limited range is threatened by logging activities, road and bridge construction, and mineral exploration within the Citico Creek watershed, where formations of anakeesta shale have been found. On contact with water, this type of shale forms poisonous sulfuric acid. The acidic water also leaches metals-particularly aluminum-from the soil, which are extremely toxic to aquatic species. Any activities that expose the shale may result in acid contamination of Citico Creek.

When shale was exposed during construction of the Tellico-Robbinsville highway in the 1970s, acidic runoff increased the concentration of sulfates, heavy metals, and acidity in Grassy Branch, a tributary of the South Fork Citico Creek. Later surveys of Grassy Branch revealed no fish life.

Several species of madtoms have been eliminated from portions of their range for unknown reasons. Biologists think that, in addition to more obvious habitat degradation, they are unable to cope with even trace amounts of complex organic chemicals that may have been added to their habitat. Organic pollution is minimal in the Citico Creek system, but any increase could jeopardize this small, isolated population.

Conservation and Recovery

Since the early 1980s, biologists with the Cherokee National Forest have studied and monitored the populations of the fish in cooperation with the University of Tennessee, Tennessee Wildlife Resources Agency, U.S. Fish and Wildlife Service, Great Smoky Mountains National Park, and a private organization, Conservation Fisheries, Inc. Research on the life histories of the species was funded by these cooperators. Annual population monitoring began in 1986. Collection of nests with eggs, followed by captive propagation in aquariums, came next.

Although successful spawning in aquariums had not been achieved as of 1994, wild-collected eggs have hatched in captivity, and fry have been reared to a size large enough for release. The fry are being stocked into Abrams Creek in the Great Smoky Mountains, another stream in which both species are believed to have occurred. If populations can be established in Abrams Creek, the species will be brought a step back from the brink of extinction.

Contacts

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

References

Bauer, B. H., G. R. Dinkins, and C. A. Etnier. 1983."Discovery of Noturus baileyi and N. flavipinnis in Citico Creek, Little Tennessee River System." Copeia 1983:558-560.

Dinkins, G. R. 1982. "Status Survey of the Smoky Madtom (Noturus baileyi )." U.S. Fish and Wildlife Service, Asheville, North Carolina.

U.S. Fish and Wildlife Service. 1985. "Smoky Madtom Recovery Plan." U.S. Fish and Wildlife Service, Atlanta.