Desert Bighorn Sheep

The Desert Bighorn Sheep is ingenious to the desert ecosystems of the Southwest United States and the northern regions of Mexico. The close relatives of these animals are the Rocky Mountain Bighorn Sheep and the Sierra Nevada Bighorn Sheep. They all descended from the ancient sheep that migrated to America from Siberia through the Bering land bridge during the Pleistocene. The differences between the modern species are the results of their adaptations to their new habitats.

The Desert Bighorn Sheep is well adapted to living in the desert. It can go without water for a long time and thrive on scarce vegetation. Some subspecies of the Desert Bighorn Sheep live in areas with no water sources. They sustain their body moisture from plants and from rain water collected in rocks. The body temperature of these animals can fluctuate several degrees to adapt to the winter cold and the heat of the day. Bighorn Sheep can lose a third of their weight and survive. They quickly recover from dehydration after drinking some water. Living in severe conditions allows the Desert Bighorn Sheep to avoid predation, since almost no predators are able to live in the desert.

For thousands of years, the Desert Bighorn Sheep was common in America, but in the middle of the 20th century, the population of all Bighorn Sheep including the Desert Bighorn Sheep dwindled to around 15,000. The major population decline occurred since the 1850s to the 1900s. These animals were hunted by the settlers for their meat and horns. Many Bighorn Sheep died because of infectious diseases transmitted by the domestic stock introduced by the settlers. Humans changed the habitat of these animals greatly and usurped the watering areas.

Since the 1960s, the population of the Desert Bighorn Sheep has been growing thanks to effective conservation measures, such as habitat preservation and organizing wildlife reserves. The present-day population of these animals is over 20,000. In some areas, they can even be hunted. The status of the Desert Bighorn Sheep is Conservation Dependent, which means that the species is out of danger, but needs protection to maintain the healthy population.