The yak, a bovid with long hairs from the Himalayas

Wild or domestic, the yak or yak occupies the highlands of Central Asia, between 3000 and 5500 meters above sea level. Wind glacial, frozen ground, thick snow and rare vegetation constitute its environment. To survive in the most hostile in the world, bovids can count on their long, double-layered fleece. Meeting with a force of nature.

The yak: one family, two varieties

The yak – ruminant mammal native to theHimalayas – belongs to the order Artiodactyla and the Bovidae family. We distinguish two varieties :

  • The yak Savage (Bos mutus), robust and powerful, measures up to 3.25 m long, 2 m shoulder height for a weight of up to 1 ton;
  • The yak domesticated (Bos grunniens) owes its scientific name to the grunts it emits (as opposed to its mute congener, mutus). Resulting from crosses with cows, this bovid displays a smaller size. Its length is approximately 3 m, its height at the withers between 130 and 170 cm and its average weight of 600 kg.

Yak: a long and protective hair

To protect the yak from bad weather and extreme cold, its fur includes two layers finely intertwined: one jar hair long and thick, especially under the belly and on the tail and a undercoat composed of a dense and woolly fill that the animal loses in summer during its moult. The fleece forms a kind of skirt partially covering its short legs whose slightly flared hooves facilitate its movements in the snow. His horns pointy grow from the sides of the head curving halfway upward. Those of females measure approximately 51 cm, against 95 cm for males. A small bump gives its back a slightly sloping appearance. Unlike the wild yak, always black plain, domesticated populations display coat tints ranging from dark brown to greyish black, with a muzzle often spotted with White. Its horns are shorter and sometimes absent. Yaks have a highly developed heart and lungs as well as a high rate of Red cells higher than that of plains cattle. This characteristic allows them to breathe better at an altitude where oxygen becomes scarce. Their poor eyesight is compensated by a very sharp smell and hearing of the yak.

The domestic yak, a survival animal

The domestic yak is used as pack animal and also provides all the essentials for the Himalayan peoples, whose meat (air dried cold and dry). His milk is drunk but also churned to make butter and cheese; her oldest boy used to make clothes, blankets, felt and ropes; her skin is used to make boots and saddlebags; finally, his dung proves to be an efficient fuel. Not very docile, the bovid is more rarely used for the work of fields. Despite its build, the yak has admirable agility, even if it means kneeling down to climb the steepest slopes.

The inhospitable habitat of the yak

Depending on whether they are wild or domestic, yaks have a habitat different :

  • Before the Chinese invasion of 1949, the wild yak was widespread over the entire Tibetan plateau north of the Himalayas. Today, he has retreated to isolated areas to flee the man. The animal occupies the desert and cold environments of the tundra, in particular the grassy hills and mountains but uninhabited, between 4,000 and 6,000 m above sea level. These regions are characterized by particularly climatic conditions. hostile : temperatures falling below -40 ° C, hail showers, snow showers, icy winds… During the coldest months of the year, the wild yak goes down to more low altitude then rises again during the warmer period;
  • the domestic yak is raised in herds on the highlands of the Himalayas (Tibet, North India, Nepal, Mongolia, China, Boutan…), between 3000 and 5000 meters of altitude. When not at work, the animal evolves in supervised liberty around villages or nomadic camps. In summer, the bovid grazes in high altitude mountain pastures where the grass is more abundant and in winter, it sleeps outside. In the event of a storm, the domestic yak takes shelter near houses or along low walls because thestable is for calves and heifers only.

Seasonal menu for the yak

The yak is a ruminant herbivore whose diet varies according to the seasons. In summer, it mainly consumes tall grass, various grasses shrubs, herbaceous plants that litter the tundra and the high meadows. In winter, the bovid feeds on dry plants found in scree, bushes emerging from the snowpack, mousse clinging to trees and lichens stuck to rocks that he manages to tear off with his tongue raspy. Due to the scarcity of vegetation, the wild yak must travel very long distances in order to find its food.

The yak: gregarious part of the year

Less competitive to reproduce, the old males live in solitary. Of a nature gregarious, the rest of the adults move in herds of 10 to 30 heads (although aggregations of 200 individuals have already been observed). In summer, the herds are only made up of females and of little ones. The males join them in the mating season and in winter. In these times, they vigorously defend their tribe by forming a circle around cows and calves. Fearful and shady, the yak does not like to be disturbed. If an intruder appears in its field of vision, it can charge quickly, stopping only a few feet away from the intruder, so as to frighten it.

Duels between yaks during the rut

The season of rut begins when temperature and humidity increase and young, nutritious grass begins to grow in pasture. This period gives rise to frequent and violent fights between males to obtain the right to mate. Every two years, after a gestation from 9 months, the female gives birth to a single young. The first one suckling occurs 10 to 30 minutes after parturition and after breastfeeding is complete, the mother and calf join the herd. the weaning intervenes after a year and the young person reaches his sexual maturity at the age of 3 or 4 years, but will not recur until around 6 or 8 years.

The wild yak, almost extinct

The yak knows only one natural predator: the Wolf. Poaching, especially for the meat trade, has considerably reduced the wild population (almost exterminated). Other threats to the animal are destruction of its habitat and crosses with the domestic variety. Its current workforce is estimated at 15,000 head against 12 millions for the domesticated yak. As such, the wild population is classified in category vulnerable on the Red List of the International Union for the Conservation of Nature (IUCN). The life expectancy of the yak is approximately 20 years.