Bighorn

The bighorn sheep is a large cloven-hoofed mammal of a rather dense and powerful physique, with short and strong limbs, a thick, short neck, small head, and a tail that protrudes slightly from the fur.

Body sizes vary in different populations, but everywhere males are on average significantly larger than females. In the Rocky Mountains, the body weight of adult males reaches 73-143 kg, while the body weight of females is only 53-91 kg. In the deserts of the southern part of the range, barnacles are smaller: body weight reaches 58–86 kg in males and 34–52 kg in females ^[2] .

The ears are relatively small. Males have heavy and massive horns, bending with a more or less gentle spiral outward. Their length is about 110 cm ^[2] . The mass of the horns of especially large males can reach 14 kg - about the same as the total weight of all other bones of the body. The horns of females are always well developed, but weaker than those of males. With a general semi-crescent shape, they sharply diverge to the sides.

Color is variable, in general, monophonic tan or brown-brown, sometimes black-brown, almost black or gray-white. The belly is light, the end of the muzzle and the back surface of the hips (“mirror”) are white. The hair is thick and long, there is no mane on the neck and chest.

The mating season falls in autumn and the beginning of winter, and in the southern part of the range in the desert, it lasts from July to December. Pregnancy lasts about 6 months, cubs are born in spring. Usually the female brings one lamb weighing 3-5 kg. Mothers are fed the young with milk for 4-6 months ^[3] .

Females are able to give birth at the age of 10-11 months, but as a rule they begin to breed in the second or third year of life. Males participate in breeding reaching a dominant position, usually at the age of about 7 years ^[4] .

Life expectancy is associated with population dynamics. If the abundance is stable or declining, bighorn sheep live for 10-19 years, and in a growing and actively breeding population - only 6-7 years ^[4] .

Bighorn herds graze during daylight hours, intermittently, herbaceous plants make up their food.

Males and females stay apart most of the year, uniting in small groups (on average 4-6 individuals in males, 6-8 in females). Lambs are with their mothers. Subsequently, females remain in the maternal group, and males aged 2-4 years leave it and join the groups of males. There are approximately two individuals per square kilometer ^[5] .

The main natural enemies of rams are wolves , bears , wolverines , cougars . Lambs, coyotes and large eagles are also dangerous for lambs.

Bighorn hills live in mountainous areas, inhabiting alpine meadows and foothills. In summer, they are held at heights of about 1800-2500 meters above sea level, in winter they go down to heights of 800-1500 meters.

In the Pleistocene (about 750,000 years ago), the ancestors of American rams crossed the Bering Isthmus and spread widely throughout North America right up to California and northern Mexico. The separation from a common ancestor into two species began about 600,000 years ago. Thin-legged rams populated Alaska and northern Canada, while bighorn sheep inhabited more southern regions. At present, hybrids of these species are very common, and the taxonomy of the subspecies of the rhino is somewhat difficult.

The livestock of the rhino at the beginning of the XIX century is estimated at 1.5-2 million individuals, but by the beginning of the XX century less than 10 thousand animals were preserved ^[6] . The reduction in numbers was due to predatory fishing, diseases and the displacement of wild sheep by domestic sheep. Subspecies Ovis canadensis auduboni , endemic to the Black Hills ridge, extinct. The high susceptibility of wild sheep to livestock diseases such as scabies and pneumonia played a significant role in this.

However, the implementation of reintroduction programs, an increase in the number of national parks amid a decrease in the number of domestic sheep by the end of World War II, led to a partial restoration of the number of American bighorn sheep. It is worth noting the unprecedented campaign to rescue the desert bighorn hills in Arizona, launched in 1936 by Major Frederick Burnham , leader of the Boy Scout movement , which resulted in the seizure of about 6,100 square kilometers. Arizona state lands for agricultural use and the creation of a reserve for the protection of wild sheep on this territory.

In the list of the International Union for Conservation of Nature, the rhino is classified as the least endangered species . In the United States, in the places where the bats are the largest, they are allowed to hunt for sports under licenses.

In honor of the bighorn sheep , several toponyms in the USA are named, in particular, the county in Montana , the county in Wyoming , the river in Wyoming and Montana

• Danilkin A.A. Bovidae. - Moscow: Partnership of scientific publications of KMK, 2005. - (Mammals of Russia and adjacent regions). - 550 copies. - ISBN 5-87317-231-5 .
• Sokolov V.E. The five-language dictionary of animal names. Mammals Latin, Russian, English, German, French. / edited by Acad. V. E. Sokolova. - M .: Rus. lang., 1984. - 352 p. - 10,000 copies.
• RM Nowak. Walker's Mammals of the World . - 6th edition. - Baltimore: The Johns Hopkins University Press, 1999. - Vol. II. - 2015 p. - ISBN 0-8018-5789-9 .

• www.iucnredlist.org: Ovis canadensis