ETWP; Proposal To Determine the Pecos Pupfish (Cyprinodon pecosensis) To Be and Endangered Species

The U.S. Fish and Wildlife Service (Service) proposes to list the Pecos pupfish (Cyprinodon pecosensis) as an endangered species without critical habitat under authority of the Endangered Species Act of 1973, as amended (Act). The historical range of the Pecos pupfish included the mainstream Pecos River and various lakes, gypsum sinkholes, saline springs, and tributaries associated with the river from the vicinity of Roswell, Chaves County, New Mexico, downstream to the vicinity of Sheffield, Pecos County, Texas. The Pecos pupfish has been replaced by sheepshead minnow (C. variegatus) x Pecos pupfish hybrids throughout more than two-thirds of its historical range. The Pecos pupfish was declining prior to introduction of the sheepshead minnow, primarily as a result of competition and depredation by nonnative fish species, and habitat loss caused by such factors as water diversion, groundwater depletion, channelization, and watershed disturbance (Sublette et al. 1990, Minckley et al. 1991). This proposal, if made final, will implement Federal protection provided by the Act for the Pecos pupfish.