Rediscovery of Headwater Catfish, Ictalurus lupus (Ictaluridae), in a Western Gulf Slope Drainage

Authors: Preston T. Bean, Michael R.J. Forstner, Timothy H. Bonner

Year: 2010 (xlii)

Abstract

Headwater catfish, Ictalurus lupus, inhabits clear spring-fed streams in southern New Mexico, southern Texas, and northeastern Mexico. Declines in I. lupus have been largely attributed to stream flow modifications, such as reduced spring flow and construction of low-head dams, and competition with channel catfish, Ictalurus punctatus. Hybridization between I. lupus and I. punctatus also poses a threat to I. lupus as habitat modifications and stocking of I. punctatus increased contact between the two species. Our analyses of cytochrome b sequences of I. lupus from the Frio River (n = 8), Devils River (n = 9), and Independence Creek (n = 5) indicated that a population of I. lupus occurs in the Frio River of the Nueces Drainage, where it was considered extirpated since 1967, and that hybridization is occurring in the Frio River and Independence Creek populations. No obvious signs of hybridization were present in the Devils River population of I. lupus.