The males, or rams, have huge brown horns with horizontal ridges. A world record class ram may have horns that way as much as 75 pounds. They curl back over the ears, down and up again past the cheeks. The females, or ewes, have smaller horns that never get larger than half a curl. Bighorn sheep have a double-layered skull honeycombed with bone struts to protect their brains during their impressive head-banging battles. Thick tendons link the skull and spine to help recoil from the impact. The rams weigh from 119-127 kg, and measure 160-180 cm from head to tail. Ewes weigh 53-91 kg and are approximately 150 cm long. 

Yews and rams usually gather in same sex groups, and go their separate way when they are not breeding. During the summer lamb-rearing season ewes stay in the upper levels of the mountains. In late fall and early winter the rams will gather up to 12 ewes into a harem. They don't defend territories, but battle other males over mating access to the females. Rams will charge each other and smash their heads together in impressive and loud battles. Age and the size of its horns determine the dominant status of a ram. Males usually don't mate until they are seven years old.

The average life span of a desert bighorn is approximately 9 years. Most sheep live for more than 10 years, except when they become overcrowded, in which case their life span is only 6-7 years. The females are led by an old ewe. Young females will usually stay with their mother's group, but the males leave when they are 2-4 years old to join a group of rams.

Desert bighorns have a long lambing season. In the Mojave Desert it begins in December and ends in June. A few lambs are even born during the summer as well. Mating can last from July to December. Their gestation time lasts about 174 days. They will have from 1-3 lambs. The females will choose a steep and safe area for the birth and raising of the lambs. The lambs are able to quickly follow their mother after only a week. Within a few weeks the lambs gather in small bands of their own, and search out their mothers only to suckle. They are completely weaned by 4-6 months. A disease has been documented in Mojave and Sonoran desert bighorns which results in high death rates for lambs from pneumonia. This disease can continue for several years and results in large population declines.

Bighorns are ruminats, which allows them to digest grass, even when it is dried out. They are mostly diurnal and will feed on and off throughout the day on a large variety of plants. The eat grasses, sedges, and forbs. They will also browse on shrubs and trees like the desert ironwood when their preferred food is scarce. The desert bighorns need water about every three days in the summer. Some wildlife refuges construct artificial water holes. However, desert bighorn sheep get a lot of their moisture from the food they eat.

The Rocky Mountain bighorns and the desert bighorns of the Mojave and Sonoran deserts are descended from the wild sheep of Central Asia. Before the last ice age the ancestors of North America's bighorn sheep crossed the Bering land bridge from the Mongolia and Tibet.

Originally the bighorn sheep were found from Baja California and Texas in the south to the Canadian Rockies. Their eastern boundary reached western Nebraska. Approximately 2 million bighorn sheep lived in North America at one time. Now they live on only 4% of their historic ranges. Today the overall population of bighorn sheep is about 25,000, with the desert bighorn sheep numbering around 4,000. Desert bighorn sheep have been nearly wiped out by diseases, over-hunting, loss of habitat, and competition with livestock. Fragmentation of their population by fences, highways and aqueducts has also contributed to some decline in their population. Access between mountains is necessary to give the desert bighorn access to other bighorn populations, thereby keeping them genetically healthy.

Bighorn Sheep are certainly one of the most prized Big Game Animals of North America! They are beautiful animals, and hunting them involves enduring great extremes of heat and cold, as well as often scaling areas that no sane person would want to try to climb through, especially for “sport!” Yet many a Trophy Hunters Dreams are filled with the Bighorn Sheep are certainly one of the most prized Big Game Animals of North America! They are beautiful animals, and hunting them involves enduring great extremes of heat and cold, as well as often scaling areas that no sane person would want to try to climb through, especially for “sport!” Yet many a Trophy Hunters Dreams are filled with the vision of taking a Magnificent Trophy Class Ram. Their interest and dedication to even successfully acquire a hunting permit takes endurance, perseverance, time and money.