Przewalski's horse is the only surviving species of wild horse. It is a prehistoric-looking horse that looks similar to those horses painted inside caves during ancient times. Humans have not domesticated this species of horse. Przewalski′s horses are genetically quite different from domesticated horses. Przewalski′s have 66 chromosomes while domestic horses have only 64.

Przewalski′s horse is also known as the Asiatic wild horse, the Mongolian wild horse, the Mongolian tarpan, and the taki. The name Przewalski comes from the man who collected a skin and skull of this horse in the late 1800s. His full name is Nikolai Mikhaylovich Przhevalski. He was a Polish-born Russian military man, an explorer, geographer, and naturalist who made several expeditions into central Asia.

Physical Description
Przewalski′s horses have tan colored hides that fade into a lighter color on muzzle and belly areas. Their stiff manes, long tails, and strong legs are dark brown. They have a dark brown stripe beginning behind the mane, continuing down the middle of the back, and to the base of the tail. Its coat goes through seasonal changes. The coat is short and darker in summer and in the winter, it grows longer, woolier, and is lighter in color.

Przewalski′s horses are small as horses go, but they have a thick muscular build. They are about 1.4 m or 4.6 ft at the shoulder. Their weight varies substantially between individuals. Przewalski′s horses weigh between 226 kg (500 lb) and 362 kg (800 lb). Their average weight is about 286 kg or 630 lb. The head is large with a long face and powerful looking jaws. This imposing head is topped with fairly long, erect ears. Przewalski′s horses lack forelock′s. This means the mane of the horse does not continue up between the ears and fall down onto the forehead. The eyes are set far back on the sides of the head towards the neck. This is an adaptation that provides the Przewalski′s horse with a wide field of view. Being able to see on both sides of themselves at one time offers them more protection from predators than animals with front-facing eyes.

Life Cycle
Przewalski′s horse live for about 35 years. Males and females reach sexual maturity at different ages. The females mature faster than males and are ready to reproduce at two to four years of age. Males reach sexual maturity when they are about five years old. When females are sexually mature, they begin going into estrus. Their estrus lasts for 5 to 22 days and females are only receptive to mating during the last 5 days.

If a female becomes pregnant during this time it will be nearly 11 months before she gives birth. The gestation period for developing foals is 329 days. Przewalski′s mares living in the northern hemisphere usually give birth sometime between April and July. Mares give birth to one foal. The foal nurses for 12 months or less. Mares may continue to reproduce up until their twenties.

Behavioral Description
Przewalski′s horses spend about 12 hours a day grazing. They travel in herds, and form two different types of groups, family groups and bachelor groups. Horses within both of these types of groups exhibit social behavior. One of these social behaviors is shared grooming. It consists of two individuals nibbling at each other′s skin, starting behind the neck, moving down to the shoulders, and finally to the back. Hierarchies within both groups are maintained through aggressive displays in the form of biting and kicking.

In the family groups, there is one lead male or stallion, and four or five mares with foals. The foals are only allowed to stay with their family group until they are between one and a half and five years old. Once they are old enough, the lead stallion chases away. The young males and females. The young females usually join a different family group. The mares within the family group have a hierarchy. There is an order of dominance, with one female at the top and a descending order thereafter. The young males join bachelor groups.

The stallion provides protection for his family group. Predators and wildfires are fairly common in their natural environment, and the stallion must keep his family group safe from these dangers. Examples of their protective behaviors and family dynamics were observed in a captive family group. A captive bred Przewalski′s stallion stood watch over his family. He was concerned about a smoke plume off in the distance. In this particular situation, the smoke was coming from a controlled burn in a nearby area. The stallion moved his mares to a position of relative safety in an area as far as possible from the smoke. With this degree of alertness, the Przewalski′s horse avoided close contact with humans for many years after other horses were domesticated.

Bachelor groups are collections of males that were driven from their family groups by a dominant stallion. This group has a hierarchy, too. One stallion in the group is considered the leader. The others follow in descending order. While the males are in this group, they learn how to control other horses. They will use this experience to help them take a family group from an older, failing stallion or start a new family group with available mares.

Habitat description
Przewalski′s horses inhabit three different biomes: desert, steppe, and mountain. They travel between these biomes in search of food and water. Their preferred habitat is grasslands with nearby water sources. The grasslands have long, cold winters and short, but very hot and dry, summers. The availability of food and water in these biomes changes with the seasons. This causes the Przewalski′s horses to move between biomes to meet their needs.

Environmental Interactions
Przewalski′s horses, like all living things, play an important role in the web of life. They are herbivorous primary consumers that eat mostly grasses. The dominant grasses in the Przewalski′s horse′s habitat belong to the plant genus Stipa. It includes Stipa baicalensis and Stipa grandis. Przewalski′s horses may also eat shrubs, bark, fruit and leaf buds. Wolves are the major wild predator of the Przewalski′s horse.

Status in the Wild
IUCN 2000: Extinct in the wild CITES: Appendix I USFS: Endangered

Population Estimates
World estimate (in captivity): about 1200
North America(in captivity): 200
Mongolia (in the wild): perhaps 60

Historical Range
(Maps are approximates)

Their range was from the Manas river to the most Northern tip of China, between Kazakhstan and Mongolia. Then, to the east to Ulaanbaatar in Mongolia.

Modern Range

They were reintroduced to the steppes near Ulaanbaatar and the Gobi desert.

Conservation Information
Contemporary threats to the Przewalski′s horse are mostly associated with habitat loss. Domestic livestock compete for the Przewalski′s horse′s grazing and water sources. Domestic livestock have displaced most of their wild counterparts in the ecosystem. In the past, water sources were even fenced off, and only domestic stock were allowed access. Other threats to the Przewalski′s horse include breeding with domestic horses, illegal capture by humans, and being hunted for meat.

Due to the Przewalski′s alert nature, capturing them has always been difficult. It was realized that shooting the mothers of young foals was the most practical way to capture Przewalski′s horses for private collections and zoos. Domesticated mares served as foster mothers for the foals. Most of the captured foals went to private collectors and just a few to select zoos. These events happened well over 100 years ago. In modern times, this behavior would be internationally condemned. Ironically, when the Przewalski′s horses became extinct in their native habitats from competition, hunting, and displacement, it was the zoo descendants of the captured foals that provided hope for the future. If these horses had not been kept in captive management, the species would most likely be extinct.

Conservation Efforts
Global captive management programs have been established because scientists are concerned with inbreeding. This is a critical program, since all Przewalski′s horses descend from 13 individuals captured as foals over a hundred years ago. This is not a small task; the cooperation of international professionals is required. Scientists perform genetic studies, make sound animal management decisions, and keep careful records.
The release of these horses into their native habitat was made possible by the efforts of concerned scientists and by the legalized protection of the Przewalski′s horses and their habitats. The released horses have already raised new foals in the wild. New programs to reintroduce more Przewalski′s horses to the wild are beginning to develop.