|The young male kouprey at the Vincennes Zoo, Paris 1937 that was designated the holotype of the species - the horns are not yet fully developed.|
A kouprey (Bos sauveli, from Khmer: គោព្រៃ, Khmer pronunciation: [koː prɨj], "wild ox"; also known as kouproh, "grey ox"), is a wild, forest-dwelling bovine species found mainly in northern Cambodia, but also believed to exist in southern Laos, western Vietnam, and eastern Thailand. It became known to zoologists in 1937.
The kouprey is believed to be a close relative to both the aurochs and the gaur. A very large ungulate, the Kouprey can approach similar sizes to the wild Asian water buffalo. These bovids measure 2.1 to 2.3 m (6.9 to 7.5 ft) along the head and body, not counting a 1 m (3.3 ft) tail, and stand 1.7–1.9 m (5.6–6.2 ft) high at the shoulder. Their weight is reportedly from 680 to 910 kg (1,500 to 2,010 lb). Unverified reports of a body mass up to 1,700 kg (3,700 lb) from Vietnam are considered dubious, since they far exceed other recorded weights for the species.
Kouprey have tall, but narrow, bodies, long legs and humped backs. They can be either grey, dark brown or black. The horns of the female are lyre-shaped with antelope-like upward spirals. The horns of the male are wide and arch forward and upward, and they begin to fray at the tips at about three years of age. Both sexes have notched nostrils and long tails.
Habitat and distribution
Historical distribution of this species included Cambodia, southern Laos, southeast Thailand, and Western Vietnam. They are now thought to be extinct in all areas outside of Cambodia. Kouprey live in low, partially forested hills, where they eat mainly grasses. Their preferred habitat is open forest and savannas often near thick monsoon forests. They are diurnal, eating in the open at night and under the forest cover during the day. They usually travel up to 15 km in a night.
They live in herds of up to 20 and are usually led by a single female. These herds generally consist of only cows and calves, but also bulls during the dry season. Older males form bachelor herds. Many herds are known to break up and rejoin as they travel and also have been found to be mixed in with herds of banteng or wild buffalo.
Kouprey graze on grasses, including bamboo, ploong, and koom. They also spend a lot of time around salt licks and water holes.
There are estimated to be fewer than 250 kouprey left in the world. There is some speculation on whether or not they are already extinct. These low numbers are attributed to uncontrolled hunting by locals and soldiers for meat, horns and skulls for use in traditional Chinese medicine, in conjunction with diseases introduced from cattle and loss of habitat due to agriculture and logging activity. Also, domestic livestock in the area could have introduced disease into the population.
Ongoing conservation efforts
Kouprey are legally protected in all range states and may be present in some protected areas. Prince Sihanouk designated it as the national animal of Cambodia in the 1960s, partly due to its mystique. Large mammal surveys continue to take place in Cambodia, hoping to rediscover living Kouprey.
Surveys have been taking place in the Kouprey's historical range as recently as 2011. These surveys were done to determine the regions within their range with the highest probability of the Kouprey's persistence. This is based on the habitat type and survey effort to date.
In 1988 an International Workshop on Kouprey Conservation was held in the University of Hanoi. This workshop worked towards the responsible government agencies and interested donors to agree upon a workable and realistic Action Plan to save the Kouprey.
However, no kouprey have been sighted since 1988, and during the last decade, several searches for the animal have proven fruitless. The 2008 IUCN report lists the kouprey as critically endangered (possibly extinct).
There is no captive population. The only individual in a western zoo was sent to the Vincennes Zoo at Paris in 1937; that was the individual designated as the holotype by Urbain. It died early in World War II.
Relation to other species
Research published by Northwestern University in London's Journal of Zoology indicated a comparison of mitochondrial sequences showed the kouprey might be a hybrid between a zebu and a banteng. However, the authors of this study have rescinded their conclusion,  and because a fossilized skull was found dating from the late Pleistocene or early Holocene epoch, they concluded the kouprey is not a hybrid. More recent genetic analysis has supported this position.
- Timmins, R.J., Hedges, S. & Duckworth., J.W. (2008). Bos sauveli. In: IUCN 2008. IUCN Red List of Threatened Species. Retrieved 29 March 2009. Database entry includes a brief justification of why this species is critically endangered.
- Grigson, C.: "Complex Cattle", New Scientist, August 4, 1988; p. 93f. URL retrieved 2011-01-27.
- Urbain, A.: "Le kou-prey ou bœuf gris cambodgien", Bulletin de la Société Zoologique de France 62(5), 1937, pp. 305–307.
-  (2011).
- Burnie D and Wilson DE (Eds.), Animal: The Definitive Visual Guide to the World's Wildlife. DK Adult (2005), ISBN 0789477645
- "Search for the kouprey: trail runs cold for Cambodia’s national animal". Phnom Penh Post, April 2006.
- http://www.iucnredlist.org/apps/redlist/details/full/2890/0 Timmins, R.J., Hedges, S. & Duckworth., J.W. 2008. Bos sauveli. In: IUCN 2008. 2008 IUCN Red List of Threatened Species. Downloaded on 11 March 2009
- Hoffmann, R. S.: "A new locality record for the kouprey from Viet Nam, and an archaeological record from China", Mammalia 50(3), pp. 391–395.
- Northwestern biologists demote Southeast Asia's 'forest ox'
- G. J. Galbreath, J. C. Mordacq, F. H. Weiler (2007) An evolutionary conundrum involving kouprey and banteng: A response from Galbreath, Mordacq and Weiler. Journal of Zoology 271 (3), 253–254. doi:10.1111/j.1469-7998.2007.00317.x
- Cambodia's National Animal Is "Real," Study Says
- Alexandre Hassanin, and Anne Ropiquet, 2007. Resolving a zoological mystery: the kouprey is a real species, Proc. R. Soc. B, doi:10.1098/rspb.2007.0830
- G. J. Galbreath, J. C. Mordacq, F. H. Weiler, 2006. Genetically solving a zoological mystery: was the kouprey (Bos sauveli) a feral hybrid? Journal of Zoology 270 (4): 561–564.
- Hassanin, A., and Ropiquet, A. 2004. Molecular phylogeny of the tribe Bovini (Bovidae, Bovinae) and the taxonomic status of the kouprey, Bos sauveli Urbain 1937. Mol. Phylogenet. Evol. 33(3):896-907.
- Steve Hendrix: Quest for the Kouprey, International Wildlife Magazine, 25 (5) 1995, p. 20-23.
- J.R. McKinnon/S.N. Stuart: The Kouprey - An action plan for its conservation. Gland, Switzerland 1989.
- Steve Hendrix: The ultimate nowhere. Trekking through the Cambodian outback in search of the Kouprey, Chicago Tribune - 19 December 1999.
- MacKinnon, J.R., S. N. Stuart. "The Kouprey: An Action Plan for its Conservation. "Hanoi University. 15 Jan. 1988. Web 13 Last Kouprey: Final Project to the Critical Ecosystem Partnership Fund for Grant Number GA 10/0.8" Global Wildlife Conservation. Austin, TX, 25 Apr. 2011. Web 13 Nov. 2013.
- Ultimate ungulate: Bos_sauveli
-  Animal info page on kouprey
-  CSEW factsheet on kouprey
- The Cryptid Zoo: Kouprey