The purpose of this project is to stock three Mohave backwaters with Bonytail chub to evaluate how the species genetics behave in an isolated system. This information will provide managers with critical information to support the use of these habitats for long-term species conservation efforts. Bonytail chub (Gila elegans, hereafter referred to as Bonytail) is one of four species of large, long-lived, endemic fishes that were once abundant and broadly distributed throughout the Colorado River basin (Minckley et al. 2003). Water development and introduction and establishment of non-native species resulted in widespread extirpation and declines in distribution and abundance of these and other native species beginning early in the 20th century. Bonytail has been adversely affected by human activities and is federally listed as an endangered species (USFWS 1980). Wild, naturally produced Bonytail are so rare that intense sampling over the past decade has produced only occasional captures in small numbers (Minckley and Thorson 2007) and the species is considered functionally extirpated in nature (Marsh 2004).