Product Code Database
The wild yak ( Bos mutus) is a large, wild Bovinae native to the Himalayas. It is the ancestor of the yak ( Bos grunniens).
Relationships of members of the genus Bos based on nuclear genomes after Sinding, et al. 2021.
They are heavily built animals with a bulky frame, sturdy legs, and rounded cloven hooves. To protect against the cold, the udder in females and the scrotum in males are small, and covered in a layer of hair. Females have four . Both sexes have long shaggy hair, with a dense woolly undercoat over the chest, flanks, and thighs for insulation against the cold. In males especially, this undercoat may form a long "skirt" that can reach the ground. The tail is long and horse-like, rather than tufted like the tails of cattle or bison. The coat is typically black or dark brown, covering most of the body, with a grey muzzle (although some wild golden-brown individuals have been reported). Wild yaks with gold coloured hair are known as the wild golden yak (). They are considered an endangered subspecies in China, with an estimated population of 170 left in the wild.
Two morphological types have been identified, so-called Qilian and Kunlun.
The primary habitat of wild yaks consists of treeless uplands between , dominated by mountains and . They are most commonly found in alpine tundra with a relatively thick carpet of grasses and sedges rather than the more barren steppe country.
The wild yak was thought to be regionally extinct in Nepal in the 1970s, but was rediscovered in Humla in 2014.Raju Acharya, Yadav Ghimirey, Geraldine Werhahn, Naresh Kusi, Bidhan Adhikary, Binod Kunwar, 2015, Wild yak Bos mutus in Nepal: rediscovery of a flagship species This discovery later resulted in the species being added to Nepal's currency.Josua Learn, 2019, Snapping the Yak: How an Iconic Photo Ended Up on Nepal's Currency
Thubten Jigme Norbu, the elder brother of the 14th Dalai Lama, reported on his journey from Kumbum in Amdo to Lhasa in 1950:
Wild yaks are herd animals. Herds can contain several hundred individuals, although many are much smaller. Herds consist primarily of females and their young, with a smaller number of adult males. On average female yaks graze 100m higher than males. Females with young tend to choose grazing ground on high, steep slopes. The remaining males are either solitary, or found in much smaller groups, averaging around six individuals. Groups move into lower altitude ranges during the winter. Although wild yaks can become aggressive when defending young, or during the rut, they generally avoid humans, and may flee for great distances if approached.
The wild yak is experiencing threats applied by several sources. Poaching, including commercial poaching, has remained the most serious threat; males are particularly affected because of their more solitary habits. Disturbance by and interbreeding with livestock herds is also common. This may include the transmission of cattle-borne diseases, although no direct evidence of this has yet been found. Conflicts with herders themselves, as in preventive and retaliatory killings for abduction of domestic yaks by wild herds, also occur but appear to be relatively rare. Recent protection from poaching particularly appears to have stabilized or even increased population sizes in several areas, leading to the IUCN downlisting in 2008. In both China and India, the species is officially protected; in China it is present in a number of large nature reserves.
Reproduction
Wild yaks mate in summer and give birth to a single calf the following spring.Wiener, G.; Jianlin, H.; Ruijun, L. (2003). "4 The Yak in Relation to Its Environment" , The Yak, Second Edition. Bangkok: Regional Office for Asia and the Pacific Food and Agriculture Organization of the United Nations, . Accessed 8 August 2008. Females typically only give birth every other year.
Conservation
The wild yak is currently listed as Vulnerable on the IUCN Red List. It was previously classified as Endangered, but was downlisted in 1996 based on the estimated rate of population decline and current population sizes. The latest assessment in 2008 suggested a total population of no more than 10,000 mature individuals.
Impact on humans
The wild yak is a reservoir for Zoonosis of both bacterial and viral origins. Such bacterial diseases include anthrax, botulism, tetanus, and tuberculosis.
External links
Notes
|
|
