Utah's wild sheep and goats: A look at bighorns and mountain goats
There are three sub-species of bighorn sheep in Utah. They are the Rocky Mountain bighorn, California bighorn and desert bighorn. They earned the “bighorn” name for the massive horns grown by the males of the species. Horns grow throughout life and reach maximum size at 8 to 10 years of age. Females also have horns about the size of yearling males.
Both male (ram) and female (ewe) bighorns grow horns but those of the rams (left) are much more impressive than those grown by the ewes (right). The horns continue to grow throughout the life of the sheep and are not shed
Bighorn sheep are native to Utah. Early native American artwork shows that wild sheep were well known to the prehistoric inhabitants of Utah. Bighorns are depicted in pictographs and petroglyphs more than any other form of wildlife.
Rams normally spend most of the year in bachelor groups separate from groups of ewes and lambs. When the breeding season begins in mid October, they seek out the ewes. At that time, rams engage in impressive head butting clashes to establish dominance. The breeding season usually lasts into early December when the rams will again leave the ewes and lambs to hang out together. Gestation is about 180 days. Lambs, which are nearly always singles, are born in mid April to early June.
Bighorns are sure footed and even lambs can climb near vertical slopes within days of being born.
Utah DWR, in partnership with local conservation groups including the Foundation for North American Wild Sheep (FNAWS) and Sportsman for Fish and Wildlife (SFW), has been involved in an aggressive program to restore bighorn sheep to their native habitat for over 40 years.
Rocky Mountain bighorns were first reintroduced near Brigham City in 1966. Desert bighorns were first reintroduced in 1973 in Zion National Park. Since restoration efforts began, over 900 Rocky Mountain bighorn sheep and over 700 desert bighorns have been released. Most desert bighorn transplants have been successful, but there have been some failures of Rocky Mountain bighorn transplants. Although the exact reasons behinds the transplant failures are unknown, disease is thought to be a major factor.
The desert bighorn (below left) is more widely distributed in Utah than the Rocky Mountain bighorn (below right).
Although similar, they are different in several ways. The desert sheep is usually lighter in color and the rams horns are often more slender with a wider spread from horn tip to horn tip.
The Rocky Mountain sheep is often more of a gray color and the rams horns appear more massive because they are usually heavier and have a tighter curl.
Rocky Mountain Bighorn Sheep
Rocky Mountain and California bighorns are very similar in appearance and habitat requirements. They prefer steep rocky slopes, and may migrate from higher elevations to lower valleys in the winter.
Rocky Mountain bighorns currently exist in the northern half of the state of Utah. All of those populations are the result of transplant efforts. The current population estimate for Rocky Mountain bighorns in Utah is approximately 1900 sheep. Of those, approximately 450 are found on National Park Service or tribal lands. California bighorns currently exist on Antelope Island State Park, the Newfoundland Mountains, and the Stansbury Mountains. The current population is estimated at 400 sheep.
One of the best places to view Rocky Mountain bighorns is the central utah town of Sunnyside during the spring and summer months. About 25 bighorn rams congregate in this area where food, cover and water are abundant. They are frequently seen near the main canyon road just east of Sunnyside. For more information on the best time to see these rams, contact the DWR.
Desert Bighorn Sheep
Desert bighorns inhabit southern Utah and are more abundant than Rocky Mountain bighorns. Significant populations occur across the Colorado Plateau including the San Rafael Swell and throughout the Colorado River and its many tributaries. The current population estimate for desert bighorns in Utah is about 3100 sheep. Of those, approximately 1000 are found on National Park Service or tribal lands.
Desert bighorns, Ovis canadensis nelsoni, prefer open rocky areas of desert mountain ranges in the south and especially southeastern parts of Utah. A native Utah species, it is popular with wildlife watchers and hunters alike.
One of the most popular places to see desert bighorns is Arches National Monument near Moab, Utah.
Desert bighorn sheep are opportunistic feeders, eating a variety of plant material, including cactus. Interestingly, desert bighorn sheep obtain a great deal of moisture from the foods they eat, and individuals can live quite some time without drinking any water.
Lambs are born in the spring; females usually give birth to only one lamb each year.
The mountain goat is native to southeastern Alaska, western Canada, and parts of northern Idaho, Montana, and Washington. Not all scientists agree, but it is likely that they were native to Utah in the past, but it did not occur in the state during recent times until the late 1960s. That was when mountain goats were re-introduced to Utah at the mouth of Little Cottonwood Canyon.
Mountain goats are sometimes called the ghosts of the cliffs because of their pure white coats and their preference for the steepest and most rugged habitat around. Mountain goats are usually found above the timberline, and are excellent rock climbers.
Mountain goats usually spend their summers at elevations of up to 13,000 feet. Even in the winter they choose slopes and windblown ridges as high as 11,000 feet. Open, precipitous cliffs are important to the survival of mountain goats. These areas provide good escape cover, feeding sites without competition from other wildlife, and birthing and nursery areas that are usually free of predators.
Because they live in areas with sparse vegetation, goats are very adaptable in their eating habits. During the summer they prefer grasses and the young branches of shrubs. WInter offers a smaller selection of good food, so goats will eat anything from twigs to pine needles.
Having salt available close by is important for mountain goats. They also like to take dust baths. It’s hard to believe that rolling around in the dirt can help them stay clean, but they always seem to be as bright and white as if their coat had been run through a wash cycle with bleach.
Females (nannies) give birth to one or two and sometimes three kids during May or June. They like to raise their kids on steep rocky slopes or cliffs. Baby mountain goats are as sure footed as their parents and can follow their mothers through rocky cliffs shortly after birth. Male mountain goats are called billies.
Even though mountain goats inhabit forbidding country, they are still popular with wildlife watchers. Many of the areas where they can be found are close to roads and established trails. People hiking the Mount Timpanogos trail often encounter goats, and the herd in Little Cottonwood Canyon can often be seen from the park-and-ride lot near the mouth of the canyon.
Mountain goats currently inhabit several mountain ranges in Utah. All are the result of introductions since 1967. Population sizes vary from the Lone Peak area in Salt Lake County, whereas many as 200 goats may be present, to Willard Peak in Box Elder County where six goats were introduced in 1994.
Utah Mountain Goat Populations
Lone Peak (east of Sandy)
Mt. Olympus (east of Sandy)
Mt. Timpanogos (east of Provo)
Provo Peak (east of Provo)
Tushar Mountains (east of Beaver)
Box Elder Peak (east of American Fork)
Willard Peak (east of Willard)
Bald Mountain (east of Kamas)
White Rocks (north of Roosevelt)
Because both billies and nannies have horns of similar lengths, it’s hard to tell the difference. Billies usually have thicker horns that curve backward in a smooth semi circle. The space between horns is about half the thickness of the horn base.
Nanny horns are thinner and have a more angular backward break near the tip. The space between horns is about 3/4 the thickness of the horn base