Smoky Madtom

The madtom is a small member of the family Ictaluridae, only reaching a maximum of 5 cm (2 in) long. It is olive brown on top with white to yellow below. Four saddles line the back of this species.

The smoky madtom is endemic to Abrams Creek in the Great Smoky Mountains National Park, Tennessee. In 1957, Chilhowee Dam was closed and an ichthyocide was administered to Abrams Creek, in an attempt to improve trout fishery. Extirpation of the smoky madtom resulted. The smoky madtom was presumed extinct until in 1980, when another population was found in Citico Creek in the Cherokee National Forest within Monroe County, Tennessee. In 1986, a restoration project was begun to restore this native population. Efforts include collecting egg masses from Citico Creek, rearing them in the lab, and reintroducing them into Abrams Creek after a year.

The smoky madtom is a very secretive catfish. During the day, it buries itself under gravel. It is nocturnal and feeds at night on aquatic invertebrates and small fish. It prefers areas of transition between pools and riffles and spawns in the summer under large, flat rocks. Specimens have been collected in areas of transition between pools and riffles in depths around 25 cm (10 in). In the winter and spring, it seems to prefer more gentle runs and pools. The area also includes large boulders for the madtom to hide under, which it has been documented to do when disturbed at night. The water is clear and its temperature is also intermediate between cold and cool water. Stream width is about 4–10 m (13–32 ft). Smallmouth bass have been recorded preying on the smoky madtoms. Noturus species can be used as an indicator of the environment because they are very susceptible to changes. Human disturbances such as logging, mining, and cattle grazing can cause siltation of the water and drop the populations dramatically. The female madtom reaches maturity after two years. Spawning happens once per year, and on average 30 eggs are produced. The life expectancy is 4 years, allowing only 2 years of reproduction, with a total of 72 eggs. This low reproduction, coupled with extirpation and low tolerance, has led the smoky madtom to be federally listed as endangered. …