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
Smoke Creek Desert Smoke Creek Desert The Smoke Creek Desert is an arid region of northwestern Nevada, USA that lies about to the north of Pyramid Lake, west of the Fox Range and east of the Smoke Creek Mountains. The southern end of the desert lies on the Pyramid Lake Indian Reservation, and a rail line lies at the eastern edge. The Smoke Creek Desert is southwest of the Black Rock Desert's South Playa and is between the Granite Range and the Fox Range. The original Smoke Creek Desert is shown on John Charles Frémont's map of the area during his 1843-44 expedition