Asiatic wild ass (Equus hemionus)

Also known as: Asian wild ass, khulan, khur, kulan, onager
French: Ane Sauvage D'Asie, Hémione, Hémippe, Onagre, Turkmene
Spanish: Asno Salvaje Asiático, Hemiono
GenusEquus (1)
SizeLength: 2 - 2.5 m (2)
Weight200 - 260 kg (2)

Classified as Endangered (EN) on the IUCN Red List (1). There are five recognised subspecies: the Mongolian wild ass (Equus hemionus hemionus) and the Indian wild ass or khur (Equus hemionus khur) are listed under Appendix I of CITES; the Turkmen kulan (Equus hemionus kulan) and the onager (Equus hemionus onager) are listed on Appendix II of CITES (3); the Syrian wild ass (Equus hemionus hemippus) is extinct (1).

The Asiatic wild ass is the most horse-like of all the species of ass (4). The general colour of its coat varies with the seasons, appearing light brown over the cold winter and reddish brown during the hot summer (2) (4). The belly, buttocks and muzzle are white, and most Asiatic wild asses, with the exception of the Mongolian wild ass (5), have a broad black dorsal stripe, bordered with white (2) (4).

Around 40,000 years ago, in the late Pleistocene era, Asian wild asses extended as far west as Germany (6). The current distribution of this species is vastly reduced (7). The Mongolian wild ass is found only in southern Mongolia and parts of northern China, but is by far the most abundant remaining subspecies. The sub-population in southern Mongolia alone accounts for almost 80 percent of the species’ entire population (5) (6). All other populations number fewer than a hundred individuals. The Indian wild ass, also known as the khur, was once found throughout the arid part of north-west India (including part of present-day Pakistan), but it is now restricted to a small area of Gujarat, India. The onager is found in two very small sub-populations in Iran. The kulan is found in Kazakhstan and Turkmenistan, where it has undergone a dramatic decline. The kulan, onager and Indian wild ass all have very small and highly isolated sub-populations, and so are at great risk of extinction caused by chance events, such as the outbreak of disease or extreme climate events (1) (6).

The Asiatic wild ass inhabits flat steppe, semi-desert or desert and is always found within 30 km of a source of water (1) (5).

The Asiatic wild ass eats grasses when available, but will browse on shrubs and trees at other times or in drier habitats (7). It has also been seen feeding on seed pods and breaking up woody vegetation with its hooves to get at more succulent herbs growing at the base of woody plants (6). During spring and summer in Mongolia, the succulent plants of the Zygophyllaceae family form an important component of the diet of the Mongolian wild ass (5). This subspecies is also known to eat snow in winter as a substitute for water (6). At other times when natural water points are unavailable, the Mongolian wild ass will dig holes in dry riverbeds to access sub-surface water. The water holes dug by the wild asses are often subsequently visited by domestic livestock, as well as other wild animals (5) (6).

Breeding is seasonal, the gestation period in this species is 11 months, and most births occur from April to September. Females with young tend to form groups of up to five females. Males have been observed holding harems of females, but in other studies they defend territories that attract females. It is likely that differences in behaviour and social structure are the result of changes in climate, vegetation cover, predation and hunting (6). In Mongolia alone, the wild ass seems to adopt harem type social groups in the southwest and territorial based social groups in the south and southeast (5). However, further research is needed to properly understand the dynamics underlying the social behaviour of this species (1) (5).   

The greatest threat facing the Asiatic wild ass is poaching for meat and hides, and in some areas for use in traditional medicine (5) (7). The extreme isolation of many of the subpopulations is, in itself, a threat, as genetic problems can result from inbreeding (7). Overgrazing by livestock reduces food availability, and herders also reduce the availability of water at springs. The cutting down of nutritious shrubs and bushes exacerbates the problem. Furthermore, a series of drought years could have devastating effects on this beleaguered species (6). Habitat fragmentation is a particular concern in Mongolia as result of the increasingly dense network of roads, railway lines and fences required to support mining activities (1) (5).

The Asiatic wild ass does occur in a number of protected sites where targeted conservation action has been taken. Domestic animals have been removed from some protected areas, and artificial watering holes have been made. Hay is provided for the species and there are hefty fines for poaching. Moreover, the species is legally protected in many of the countries in which it occurs (6). The priority for future conservation measures is: to ensure the protection of this species in particularly vulnerable parts of its range; to encourage the involvement of local people in the conservation of the Asiatic wild ass; and to conduct further research into the behaviour, ecology and taxonomy of the species (1). Fortunately several Asiatic wild ass research programmes considering these issues are already underway (5) (6).

For further information on the conservation of the Asiatic wild ass see:

Authenticated (23/12/2008) by Anne-Camille Souris, Ethologist, member of the SSC/IUCN Equid Specialist Group, and President of Goviin Khulan:

  1. IUCN Red List (January, 2009)
  2. Nowak, R.M. (1991) Walker’s Mammals of the World. The Johns Hopkins University Press, Baltimore and London.
  3. CITES (January, 2009)
  4. Macdonald, D.W. (2006) The Encyclopedia of Mammals. Oxford University Press, Oxford.
  5. Souris, A.C. (2009) Pers. comm.
  6. Feh, C., Shah, N., Rowen, M., Reading, R. and Goyal, S.P. (2002) Status and Action Plan for the Asiatic Wild Ass (Equus hemionus). In: Moehlman, P.D. (Ed.) Equids: Zebras, Asses, and Horses: Status Survey and Conservation Action Plan. IUCN/SCC Equid Specialist Group, IUCN, Gland Switzerland and Cambridge, UK. Available at:
  7. IUCN/ AAC Equid Specialist Group (March, 2004)