Desert bighorn sheep facts for kids
Quick facts for kids Desert bighorn sheep |
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| Conservation status | |
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Sensitive (BLM)
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Scientific classification  |
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| Kingdom: | Animalia |
| Phylum: | Chordata |
| Class: | Mammalia |
| Order: | Artiodactyla |
| Family: | Bovidae |
| Subfamily: | Caprinae |
| Genus: | Ovis |
| Species: | |
| Subspecies: |
O. c. nelsoni
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| Trinomial name | |
| Ovis canadensis nelsoni Merriam, 1897
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The desert bighorn sheep (Ovis canadensis nelsoni) is a special kind of bighorn sheep. These amazing animals live in the hot deserts of the southwestern United States and northwestern Mexico.
This sheep's scientific name honors an American naturalist named Edward William Nelson. Desert bighorn sheep act much like other bighorn sheep. However, they have amazing ways to live without much water in the desert. They can go a long time without needing a drink!
The desert bighorn sheep is also the animal symbol for the Universidad Autónoma de Baja California in Mexico.
Contents
Where Do Desert Bighorn Sheep Live?
Desert bighorn sheep can be found in many deserts. These include the Mojave Desert, Sonoran Desert, Great Basin Desert, and Chihuahuan Desert. They also live in the Colorado Plateau area.
Many national parks and wildlife refuges help protect them. Places like Anza-Borrego Desert State Park, Joshua Tree National Park, Death Valley National Park, and Zion National Park are safe homes for these sheep.
Their numbers dropped a lot when people from Europe first settled in the American Southwest. But then, people started working to protect them. This helped their populations grow again. Even though their numbers were very low in 2004, they have been slowly increasing since the 1960s.
What Do Desert Bighorn Sheep Look Like?
Desert bighorn sheep are strong, heavy animals. They are about the same size as mule deer. Adult males, called rams, can weigh from 115 to 280 pounds (52 to 127 kg). Females, called ewes, are a bit smaller.
These sheep have special hooves that help them climb. Their hooves are curved and springy. This allows them to move quickly and easily on steep, rocky desert mountains. They have excellent eyesight to spot dangers. If a mountain lion, coyote, or bobcat tries to hunt them, they use their climbing skills to escape.
Both male and female sheep grow horns soon after they are born. Their horns keep growing throughout their lives. Older rams have huge, curling horns that can be over three feet long. These horns can be more than a foot around at the base. Ewes have much smaller and lighter horns that do not curl as much. A ram's horns can weigh over 30 pounds when it's eight years old! You can tell a sheep's age by counting the growth rings on its horns. Rams sometimes rub their horns to help them see better. Both rams and ewes use their horns to break open cactus to eat and for fighting.
Desert bighorn sheep usually live for 10 to 20 years. They mostly eat grasses. If grass is hard to find, they will eat other plants like sedges, forbs, or even cactus.
How Do They Survive in the Desert?
Desert bighorn sheep are very good at living in the desert. They can handle both the heat and the cold. Unlike most mammals, their body temperature can change a few degrees safely. During the hottest part of the day, they often rest in the shade of trees or in caves.
These sheep are amazing because they can live in desert mountains with very little water. Some can go for weeks or even months without drinking! They get moisture from their food and from rainwater that collects in temporary rock pools. They can even lose up to 30% of their body weight from dehydration and still survive. After they drink water, they quickly get back to normal. This special ability helps small groups of bighorns live in places too dry for many animals that might hunt them.
How Do Desert Bighorn Sheep Live Together?
Desert bighorn sheep are social animals. They usually form groups of eight to 10 sheep. Sometimes, much larger groups of 100 sheep can be seen.
Male rams will fight each other to decide which one is the strongest. The strongest ram then gets to mate with the ewes. Rams charge at each other from about 20 ft (6.1 m) away. They crash their huge horns together with a loud sound until one of them gives up.
Most of the year, male and female sheep live in separate groups. They come together during the breeding season, which is usually from July to October. However, in the desert, they can breed at any time if the weather is good. Baby lambs are born after about 150 to 180 days, usually in late winter.
Protecting Desert Bighorn Sheep
We don't know exactly how many desert bighorn sheep lived in North America long ago, but it was probably tens of thousands. By the 1960s, their numbers had dropped to only about 6,700 to 8,100. This happened because of too much hunting, diseases from farm animals like domestic sheep, and people taking over their water sources and living areas.
In 1939, President Franklin D. Roosevelt helped create two special desert areas in Arizona. These areas, Cabeza Prieta National Wildlife Refuge and Kofa National Wildlife Refuge, were made to help protect the desert bighorn sheep. Later, in 1941, the San Andres National Wildlife Refuge in New Mexico was also added.
| State | 1960 | 1993 | 2018 |
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| Arizona | 3,000-3,500 | 6,000 | 5,000-5,500 |
| California | 2,140-2,450 | 4,300-4,325 | 5124 |
| Colorado | 0 | 475 | 540 |
| Nevada | 1,500-2,000 | 5,294 | 10,300 |
| New Mexico | 400-500 | 295 | 1,200 |
| Texas | 25 | 401 | 1,500 |
| Utah | Remnant | 2,200-2,250 | 2,900 |
| Total | 7,065-8,475 | ~19,000 | ~26,800 |
The number of desert bighorn sheep has been going up since the 1960s. This is thanks to efforts to protect their habitat (the places they live). In 1980, there were about 8,415 to 9,040 sheep. By 1993, the number grew to about 18,965 to 19,040. The table on the right shows how their populations have changed in different states.
In southwestern Utah, desert bighorns had almost disappeared by 1960. But in 1978, 14 sheep were brought back to Zion National Park. Now, the herd has grown to over 500 animals! They sometimes even meet visitors in the park.
In southern California, a specific group called the peninsular bighorn sheep had only 280 individuals left by 1998. They were added to the list of endangered species. Their numbers had dropped because of disease, new buildings, and predators. By 2008, about 800 peninsular bighorns were living in the desert from the US-Mexico border up to the San Jacinto Mountains. Many live in Anza-Borrego Desert State Park.
In southern Texas, efforts to save the desert bighorn sheep started in 1973. Seven sheep that were raised in captivity were released into the Sierra Diablo Mountains. More captive-bred sheep were released there until 1997. Another group started in 1987 with 20 sheep at the Elephant Mountain Wildlife Management Area. This group has grown a lot and has provided sheep for other areas in Texas.
Some groups of sheep didn't do as well, like the one near Van Horn, Texas. They faced challenges from mountain lions. But overall, many efforts have helped these sheep. Scientists often put radio collars on the sheep to track their movements and learn more about them.
A very small number of hunting permits are given out each year in Texas. Money from these permits helps pay for conservation work for the bighorn sheep.
See also
In Spanish: Borrego del Desierto para niños
