Noturus munitus

Populations in the Pearl and Mobile basins should be investigated for possible polytypy (Starnes 1995, who referred to this fish as the "freckled madtom"). See Grady and LeGrande (1992) for a study of phylogenetic relationships, modes of speciation, and historical biogeography of Noturus madtom catfishes. See Lundberg (1992) for a synthesis of recent work on the systematic relationships of ictalurid catfishes.

Spotty distribution in Louisiana, Mississippi, Alabama, and Tennessee; significant decline in distribution and abundance; threatened by various alterations to stream habitat (dredging, siltation, impoundment, etc.).

Range includes the Pearl River, eastern Louisiana and southern Mississippi; Tombigbee River, eastern Mississippi and western Alabama; upper Alabama (likely extirpated) and Cahaba rivers, central Alabama; Etowah River, northern Georgia; Conasauga River, northern Georgia and southeastern Tennessee (Bennett et al. 2008, 2010; Page and Burr 2011). Probably this species was formerly more widespread in the Mobile Bay drainage.

Current range: Pearl River drainage (Bogue Chitto River, lower Pearl River and tributaries); upper Tombigbee River drainage (East Fork, Buttahatchie River, lower Luxapallila Creek, Sipsey River; Alabama and Cahaba river drainages (lower Cahaba River); Etowah River system (upper Etowah River); Conasauga River system (middle Conasauaga River) (Bennett et al. 2010).

On a coarse level, this species currently is represented by 9 patches of occupied habitat (see map in Bennett et al. 2010).

This madtom is very difficult to survey due to its small size, secretive nature, and nocturnal, benthic, and cryptic life style (P. Shute, pers. comm., 1997), so available data may not reflect the full distribution and abundance of the species.

This small fish's movements are impeded by dams and impoundments. The species disappeared abruptly from the Alabama River after construction of the Millers Ferry and Claiborne dams and associated navigational modifications of the river channel (Ramsey 1976). It is expected to disappear from the main channel of the upper Tombigbee because of the impoundment and canalization of the river by the Tennessee-Tombigbee Waterway, though hopefully it will survive in large tributaries (Boschung and Mayden 2004).

High levels of siltation within streambeds constitute poor habitats for the species (Shepard 1996).

Jelks et al. (2008) categorized the Cahaba population as vulnerable, Coosa population as endangered, Pearl population as vulnerable, and Tombigbee population as endangered, based on the present or threatened destruction, modification, or reduction of habitat or range, combined with a narrowly restricted range.

This species is regarded as very threatened; the greatest threat is probably siltation followed by habitat modifications due to impoundment, channelization (Shephard et al. 1996; P. Shute, pers. comm., 1997), gravel removal operations, and altered flow regimes (Shephard et al. 1996). Populations in the Tombigbee and Alabama rivers have dwindled in recent years, primarily because of the construction and maintenance of inland waterways that have destroyed most of the permanent gravel bars (Mettee et al. 1996). Other threats include nonpoint source pollution related to activities such as silviculture, agriculture, and construction in the watersheds. Gravel removal and washing in the Buttahatchie River has degraded some habitat in that system, and channelization for flood control has drastically reduced the population in Luxapallila Creek due to loss of habitat and increased sediment loads (Shepard, pers. comm., 1997).

Frecklebelly darters are regarded by some as fairly resistant to nondestructive intrusion (S. Shively, pers. comm., 1997), but others consider them fragile and susceptible to nondestructive intrusion (P. Shute, pers. comm., 1997).