Przewalski's Horse (Equus ferus przewalskii, Mongolian: Тахь, Takhi; Chinese: 野马 Yehmah/Yěmǎ), or Dzungarian Horse, is a rare and endangered subspecies of wild horse (Equus ferus) native to the steppes of central Asia. In China, the last wild Przewalski's horses were seen in 1966. The Przewalski's Horse Reintroduction Project of China was initiated in 1985 with the creation of the Xinjiang Wild Horse Breeding Center. At one time extinct in the wild, it has been reintroduced to its native habitat in Mongolia at the Khustain Nuruu National Park, Takhin Tal Nature Reserve and Khomiin Tal. The taxonomic position is still debated, and some taxonomists treat Przewalski's Horse as a species, Equus przewalskii.
Common names for this equine include Asian Wild Horse and Mongolian Wild Horse. Historical but obsolete names include true tarpan and Mongolian tarpan. In English, Przewalski is pronounced /ʃɨˈvælskiː/ or /zɨˈvɑːlskiː/ (the Polish pronunciation is [pʂɛˈvalski]). The horse is named after the Russian geographer and explorer Nikolai Przhevalsky.
Most "wild" horses today, such as the American Mustang or the Australian Brumby, are actually feral horses descended from domesticated animals that escaped and adapted to life in the wild. In contrast, Przewalski's Horse has never been successfully domesticated and remains a truly wild animal today. Przewalski's Horse is one of two known subspecies of Equus ferus, the other being the extinct Tarpan (Equus ferus ferus). The Przewalski's Horse is considered the only remaining truly wild "horse" in the world and may be the closest living wild relative of the domesticated horse, Equus caballus. There are still a number of other wild equines, including three species of zebra and various subspecies of the African wild ass, onager and kiang.
The Przewalski's Horse was described in 1881 by L.S. Poliakov. The taxonomic position of Przewalski's Horse has always been problematic and no consensus exists whether it is a full species (Equus przewalskii), a subspecies of the wild horse (Equus ferus przewalskii) or even a sub-population of the domesticated horse (Equus caballus). Studies using DNA have been inconclusive, in part due to crossing domestic horses into the Przewalski's Horse as well as the limited genetic variation present in the founder population of the Przewalski's Horse. A recent molecular studies using ancient DNA (that is DNA recovered from archaeological finds like bones and teeth) places the Przewalski's Horse in the middle of the domesticated horses, but no definitive answers have been given.
The world population of these horses are all descended from 9 of the 31 horses in captivity in 1945. These nine horses were mostly descended from approximately 15 captured around 1900. A cooperative venture between the Zoological Society of London and Mongolian scientists has resulted in successful reintroduction of these horses from zoos into their natural habitat in Mongolia; and as of 2005 there is a free-ranging population of 248 animals in the wild. The total number of these horses according to a 2005 census was about 1,500.
Przewalski's Horse is stockily built in comparison to domesticated horses, with shorter legs. Typical height is about 13 hands (1.32 m), length is about 2.1 m with a 90 cm tail. They weigh around 300 kilograms (660 lb). The coat is similar to dun coloration in domestic horses. It varies from dark brown around the mane (which stands erect) to pale brown on the flanks and yellowish-white on the belly. The legs of Przewalski's Horse are often faintly striped.
In the wild, Przewalski's Horses live in social groups consisting of a dominant stallion, a dominant lead mare, other mares, and their offspring. The patterns of their daily lives exhibit horse behavior similar to that of feral horse herds: Each group has a well-defined home range; within the range, the herd travels between three and six miles a day, spending time grazing, drinking, using salt licks and dozing. At night, the herd clusters and sleeps for about four hours. Ranges of different herds may overlap without conflict, as the stallions are more protective of their mares than their territory.
Stallions practice a form of scent marking and will establish piles of dung at intervals along routes they normally travel to warn other males of their presence. In addition, when a female in the herd urinates, the stallion will frequently urinate in the same place, to signal her membership in the herd to other males. The stallions can frequently be seen sniffing dung piles to confirm scent markings.
In the 15th century, Johann Schiltberger recorded one of the first European sightings of the horses in the journal of his trip to Mongolia as a prisoner of the Mongol Khan. The horse is named after the Russian colonel Nikolai Przhevalsky (1839–1888) (the name is of Polish origin, and "Przewalski" is the Polish spelling). He was an explorer and naturalist who described the horse in 1881, after having gone on an expedition to find it, based on rumors of its existence. Many of these horses were captured around 1900 by Carl Hagenbeck and placed in zoos. As noted above, about twelve to fifteen reproduced and formed today's population.
The native population declined in the 20th century due to a combination of factors, with the wild population in Mongolia dying out in the 1960s. The last herd was sighted in 1967 and the last individual horse in 1969. Expeditions after this failed to locate any horses, and the species was designated "extinct in the wild" for over 30 years.
After 1945 only two captive populations in zoos remained, in Munich and in Prague. The most valuable group, in Askania Nova, Ukraine, was shot by German soldiers during World War II occupation, and the group in the USA had died out.
In 1977, the Foundation for the Preservation and Protection of the Przewalski Horse was founded in Rotterdam, the Netherlands, by Jan and Inge Bouman, which started a program of exchange between captive populations in zoos throughout the world to reduce inbreeding, and later starting a breeding program of its own. In 1992, sixteen horses were released into the wild in Mongolia, followed by additional animals later on. One of the areas to which they were reintroduced became Khustain Nuruu National Park in 1998.
The reintroduced horses successfully reproduced, and the status of the animal was changed from "extinct in the wild" to "endangered" in 2005. On the IUCN Red List, they were reclassified from "extinct in the wild" to "critically endangered" after a reassessment in 2008.
While dozens of zoos worldwide have Przewalski's Horses in small numbers, there are also specialized reserves dedicated primarily to the species.
The world's largest captive breeding program for Przewalski's horses is at the Askania Nova preserve in Ukraine. Several dozen Przewalski's horses were also released in the area evacuated after the Chernobyl accident, which now serves as a deserted de facto natural preserve. An intensely researched population of free-ranging animals was also introduced to the Hortobágy puszta in Hungary; data on social structure, behavior, and diseases gathered from these animals is used to improve the Mongolian conservation effort.
Recent advances in equine reproductive science have potential to further preserve and expand the gene pool. In October, 2007 scientists at the Smithsonian Institution's National Zoo successfully reversed a vasectomy on a Przewalski horse — the first operation of its kind on this species and possibly the first ever on any endangered species. While normally a vasectomy may be performed on an endangered animal under limited circumstances, particularly if an individual has already produced many offspring and its genes are overrepresented in the population, scientists realized the animal in question was one of the most genetically valuable Przewalski horses in the North American breeding program.
The Przewalski's Horse Reintroduction Project of China was initiated in 1985 when the country introduced 11 wild horses from overseas. After more than two decades of dedicated efforts, the Xinjiang Wild Horse Breeding Center managed to breed a large number of the horses, of which 55 were let loose into the Kalamely Mountain area. The animals quickly adapted to their new environment. In 1988, six foals were born and survived. In 2001 there were over 100 horses at the center. Now both their reproduction rate and survival rate are the highest in the world.
|Wikimedia Commons has media related to: Equus przewalskii|
- ^ a b Boyd, L.; Zimmermann, W. & King, S.R.B (2008). "Equus ferus ssp. przewalskii". 2008 IUCN Red List of Threatened Species.. IUCN. http://www.iucnredlist.org/apps/redlist/details/7961/0/full. Retrieved 2009-02-01.
- ^ "The Takhi". International Takhi-Group. http://www.takhi.org/cms/index.php?option=com_content&task=view&id=28&Itemid=50&lang=en. Retrieved 2009-02-01.
- ^ "Przewalski's Horse Facts". National Zoo. http://nationalzoo.si.edu/animals/asiatrail/fact-phorse.cfm. Retrieved 2009-02-01.
- ^ William Ridgeway (1908). "Environment and race". The Geographical Journal 32: 405–412. doi:10.2307/1776930. http://books.google.com/books?id=MqgMAAAAIAAJ&pg=PA407&dq=tarpan. , page 407
- ^ lau, Allison; Lei Peng, Hiroki Goto, Leona Chemnick, Oliver A. Ryder, Kateryna D. Makova (2009). "Horse Domestication and Conservation Genetics of Przewalski’s Horse Inferred from Sex Chromosomal and Autosomal Sequences". Mol. Biol. Evol. 26 (1): 199–208. doi:10.1093/molbev/msn239.
- ^ Kavar, Tatjana; Peter Dovč (2008). "Domestication of the horse: Genetic relationships between domestic and wild horses". Livestock Science 116: 1–14. doi:10.1016/j.livsci.2008.03.002.
- ^ a b Cai, Dawei; Zhuowei Tang, Lu Han, Camilla F. Speller, Dongya Y. Yang, Xiaolin Ma, Jian’en Cao, Hong Zhu, Hui Zhou (2009). "Ancient DNA provides new insights into the origin of the Chinese domestic horse". Journal of Archaeological Science 36: 835–842. doi:10.1016/j.jas.2008.11.006.
- ^ Boyd, Lee. (1994). Przewalski's Horse, p. 1.
- ^ a b "An extraordinary return from the brink of extinction for worlds last wild horse" ZSL Living Conservation, December 19, 2005.
- ^ National Zoo information on Przewalski's Horse
- ^ Breeds of Livestock - Przewalski Horse
- ^ IUCN Red List - Equus ferus
- ^ Mulvey, Stephen (2006-04-20). "Wildlife defies Chernobyl radiation". BBC News (BBC). http://news.bbc.co.uk/2/hi/europe/4923342.stm. Retrieved 2007-10-03.
- ^ "Zoo Performs First Reverse Vasectomy on Horse" The Horse online edition, citing Associated Press, June 17, 2008.
- Boyd, Lee and Katherine A. Houpt. (1994). Przewalski's Horse: The History and Biology of an Endangered Species. Albany, New York: State University of New York Press. 10-ISBN 0-791-41889-8; 13-ISBN 978-0-791-41889-5; OCLC 28256312
- Forestry Commission. 2004. FC Wales turns clock back thousands of years with 'wild' solution to looking after ancient forest site. News release, No: 7001, 16 September 2004. 
- International Commission on Zoological Nomenclature. 2003. Opinion 2027 (Case 3010). Usage of 17 specific names based on wild species which are pre-dated by or contemporary with those based on domestic animals (Lepidoptera, Osteichthyes, Mammalia): conserved. Bull.Zool.Nomencl., 60:81-84. .
- Ishida, Nobushige; et al. (1995). "Mitochondrial DNA sequences of various species of the genus Equus with special reference to the phylogenetic relationship between Przewalskii's wild horse and domestic horse". Journal of Molecular Evolution 41 (2): 180–188. doi:10.1007/BF00170671.
- Jansen, Thomas; et al. (2002). "Mitochondrial DNA and the origins of the domestic horse". PNAS 99 (16): 10905–10910. doi:10.1073/pnas.152330099. PMID 12130666.
- King, S. R. B.; Gurnell, J. (2006). "Scent-marking behaviour by stallions: an assessment of function in a reintroduced population of Przewalski horses (Equus ferus przewalskii)". Journal of Zoology 272 (1): 30–36. doi:10.1111/j.1469-7998.2006.00243.x.
- Wakefield, S., Knowles, J., Zimmermann, W. and Van Dierendonck, M. 2002. "Status and action plan for the Przewalski's Horse (Equus ferus przewalski)". In: P.D. Moehlman (ed.) Equids: Zebras, Asses and Horses. Status Survey and Conservation Action Plan, pp. 82–92. IUCN/SSC Equid Specialist Group. IUCN, Gland, Switzerland and Cambridge, UK. 
- Wilford, John Noble (2005-10-11). "Foal by Foal, the Wildest of Horses Is Coming Back". New York Times. http://www.nytimes.com/2005/10/11/science/11hors.html.
- Cao Jie, Przewalski's Horse Reintroduction Project of China