After a journey of nearly 1,000 kilometers from Wuwei in northwest China’s Gansu province, the 21 Przewalski horses have arrived at the Xihu Nature Reserve.
Przewalski’s horses historically live on grasslands that are part of China’s Xinjiang Uygur autonomous region and Mongolia. China and Mongolia are the only two countries that have successively released Przewalski’s horses into the wild. The species faced extinction after rampant hunting that began in the early 19th century.
Currently, there are fewer than 1,500 domestically-bred Prezewalski’s horses in the world. And China has been breeding the species since 1985, when 11 wild horses were imported from overseas.
China’s State Forestry Administration, together with Forestry department in northwest China’s Gansu Province has decided to release 21 Przewalski’s horses and four camels into the wild. The staff move the horses in crates from the truck.
The crates have to remain on the ground for a while for the horses to adapt to the environment. The staff check the horses’ blood pressure and heart beat rate. The two female camels are also released into the reserve, joining the two males there. The camels are being fitted with tracking devices.
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 three known subspecies of Equus ferus, the others being the domesticated horse, Equus caballus and the extinct tarpan. The Przewalski horse is considered the only remaining truly wild "horse" in the world and may be the closest living wild relative of the domesticated horse.
In the wild, Przewalski horses live in small, permanent family groups consisting of one adult stallion, one to three mares, and their common offspring. Offspring stay in the family group until they are no longer dependent, usually at 2 or 3 years old. Bachelor stallions, and sometimes old stallions, join bachelor groups. Family groups can join together to form a herd that move together.
The patterns of their daily lives exhibit horse behavior similar to that of feral horse herds. Stallions herd, drive and defend all members of their family, while the mare often displays leadership in the family. Stallions and mares stay with their preferred partner for years.
Horses stay in their herds at all times and have a host of ways to communicate with one another, including vocalizations, scent marking, and a wide range of visual and tactile signals. Each kick, groom, tilt of the ear, or other contact with another horse are means of communicating. This constant communication leads to complex social behaviors among Przewalski horses.
The world’s largest captive breeding program for Przewalski horses is at the Askania Nova preserve in Ukraine. Several American zoos also collaborated in breeding Equus ferus przewalskii from 1979 to 1982. Recent advances in equine reproductive science in the United States also 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.