Scioto Madtom

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Scioto Madtom

Noturus trautmani

StatusEndangered
ListedSeptember 25, 1975
FamilyIctaluridae (Catfish)
DescriptionSmall dusky olive or dark brown catfish with a milky white belly and four dark saddle markings across its back.
HabitatStream riffles or moderate flow over gravel substrate.
FoodBottom browsing on plant matter and detritus.
ReproductionProbably spawns in summer, depositing eggs in nests.
ThreatsCritically low numbers.
RangeOhio

Description

The Scioto madtom, Noturus trautmani, is a small catfish ranging from 1.4 to 2.3 in (3.6 to 6 cm) in length. Its coloration is a dusky olive or dark brown, mottled with gray. There are four distinct, dark saddle markings across the back. The belly is unspotted and milky white. The caudal (tail) fin is marked by a dark bar or crescent while the adipose fin is yellowish. It has a slender, scaleless body, broad flat head, long barbels around the mouth, and sharp, heavy pectoral and dorsal spines. Pricks from these spines are strongly irritating to humans.

Behavior

It is assumed that the Scioto madtom is a bottom browser and, like most of its relatives, feeds on plant and animal detritus. Feeding occurs primarily at night and food items are identified by the barbels. The madtom becomes inactive during the day and remains hidden in the substrate.

Although breeding sites have not been located, this species is thought to spawn in summer and migrate downstream in the fall. Madtoms deposit eggs in nests located in depressions or cavities. The male guards both the nest and the young for up to several weeks following hatching.

Habitat

Based on habitat conditions in its former range, it would appear that the Scioto madtom prefers stream riffles of moderate flow over a substrate of gravel. Water is of generally high quality with little suspended sediment.

Distribution

This species was first collected in 1943 from Big Darby Creek (Pickaway County), a tributary of the Scioto River basin. It is thought to be endemic to this central Ohio watershed. Only 18 specimens have ever been netted, most in a single stretch of creek near the village of Fox.

Few rare fish have been sought as avidly as the Scioto madtom, but it has not been collected since 1957, and many biologists have declared it extinct. If this madtom still exists, it survives in very low numbers. Intensive surveys in suitable habitats in adjacent drainages between 1981 and 1985 failed to located any specimens of the Scioto madtom. Only 18 specimens are known to have been collected at all, and most of these were from a fairly small area of Big Darby Creek.

Threats

Because no population centers have ever been located, it is difficult to determine what, if any, environmental factors have contributed to the Scioto madtom's decline. However, the construction of impoundments on Big Darby Creek and the Scioto River increased siltation, and the pollution level has generally increased, both of which could have contributed to the madtom's decline.

Conservation and Recovery

Although this fish may be extinct, the Fish and Wildlife Service has deemed it prudent to maintain its Endangered status. If a population is rediscovered, it will be afforded immediate protection under the provisions of the Endangered Species Act. If the species is removed from the list and then re-discovered, the entire listing process would have to be reinitiated.

Contact

Regional Office of Endangered Species
U.S. Fish and Wildlife Service
Federal Building, Fort Snelling
Twin Cities, Minnesota 55111
http://midwest.fws.gov/

Reference

Trautman, M. B. 1981. The Fishes of Ohio. The Ohio State University Press, Columbus.