Abstract
Shoshone pupfish {Cyprinodon nevadensis shoshone Miller), previously <br /><br />considered extinct, were rediscovered in 1986 from the outflow of Shoshone <br /><br />Spring. Plans to expand use of the water supply prompted us to map Shoshone <br /><br />Spring and determine habitat quality and distribution and abundance of pupfish. <br /><br />Pupfish in Shoshone Spring are threatened by habitat alteration, including reduced <br /><br />instream flow and pollution, and predation by and/or competition with introduced <br /><br />mosquitofish (Gambusia affinis). Because the continued existence of pupfish in <br /><br />Shoshone Spring seemed unlikely, we removed fish to establish a protected pop- <br /><br />ulation to provide progeny for reintroduction.