An onager is an equid, meaning that it is in the horse family, and it is more formally known as Equus hemionus. Onagers once roamed across much of Asia, but due to hunting and shrinking habitat, these animals are now much less abundant than they once were. Many of the world’s onagers live in zoos today, where biologists hope to rebuild stocks of onagers with breeding programs to save these plucky, feisty, and currently endangered animals.
Like their relatives the horses, onagers are hooved animals with stocky, muscular bodies designed for quick flight. The onager is also extremely agile, able to navigate rough and rocky terrain within hours of birth, and the animals are famous for being able to jump very high. They can also withstand brutal conditions including extreme heat and cold, which may explain why they were once widely distributed across the plains of Asia, as they were able to adapt to rough and changing conditions.
In appearance, an onager looks a little like a small donkey. The animals have creamy underbellies and darker rusty orange fur on their backs and hindquarters, with a bold black stripe running down their backs. Like many wild equids, the onager has an upright mane, and its tail is a small stub which is useful for sweeping away flies and other pests.
In the wild, onagers tend to roam in herds which vary in size, depending on a variety of conditions. Stallions have been known to fight viciously over mares in season. There are several onager herds in places like Iran and Russia, but these herds are rather small, and biologists are concerned that they may be lacking in genetic diversity, which could lead to problems for rare onager subspecies. These animals are also threatened by hunting, ecological damage in the areas they live in, and ever-expanding human habitation.
Historically, the onager was used as a source of prey by the Persians, and some evidence suggests that the Persians may have captured and bred onagers as well. These animals are said to be extremely challenging to tame and domesticate, which may explain why people ride the more docile and predictable horse today, rather than the onager or another equid such as the zebra. If you live near a major zoo, you may be able to see an onager or two for yourself; several zoos in Europe and the United States have established successful breeding programs which showcase several subspecies of onager such as the Iranian Ass and the Mongolian Wild Ass.