Desert bighorn sheep establish two desert areas in southwestern Arizona to help preserve the desert bighorn sheep: Cabeza Prieta National Wildlife Refuge and the Kofa National Wildlife Refuge. In 1941, the San Andres National Wildlife Refuge in New Mexico was added. Desert bighorn sheep populations have trended upward since the 1960s when their population was estimated at 6,700-8,100. The upward trend was caused by conservation measures, including habitat preservation. In 1980, desert bighorn sheep populations were estimated at 8,415-9,040. A state-by-state survey was conducted a few years later and estimated the overall US desert bighorn sheep population at 15,980. The 1993 estimate of
East Desert Range Range) to Desert Valley and Desert Lake to the west of the Sheep Range. The region also contains Surprise Canyon, which flows due west into the east of Dog Bone Lake in Three Lakes Valley. East Desert Range The East Desert Range is a mountain range in Lincoln County, Nevada. The range is northwest-southeast trending around the Three Lakes Valley where Dog Bone Lake is the large landform in the valley flatlands. The range sits mostly to the north and northeast of Three Lakes Valley. The southern terminus of the range lies in a mixture of hills associated with the