Sunday, December 13, 2009

Wild Asses All Over the World Critically Endangered

Wild Nubian Ass

Sleek, graceful, proud, and majestic, wild members of the horse family Equidae (horses, zebras, and wild asses) have long held a strong fascination for humans. Found in some of the most unlivable habitats in the world, wild asses are able to eke out a living and thrive where most animals could not. Some wild asses are also known as kulans, onagers, and kiangs. They differ from horses and zebras in their smaller size, larger ears, tufted tail, stiff mane, and characteristic loud bray. Wild asses are intelligent creatures, with excellent vision and hearing. They'd rather run from predators than fight. If cornered, though, they will kick hard to protect themselves. One swift kick from the business end of a sharp hoof is enough to drive away most predators!

A wild design
All wild asses have bristly upright manes like their zebra relatives. The African wild asses Equus africanus have soft gray bodies, white bellies, spiky black-and-gray manes, and unique black and white stripes on their legs that also hint of their family connections! The wild asses native to Asia are either pale tan or reddish in color with white bellies and lack the leg stripes of their African cousins. They are also slightly larger than their African counterparts. They stand about 4 feet tall (1.2 meters) at the shoulder and have small, narrow hooves-the smallest of all the equids-which help them move quickly and safely through their stony habitat. It is this small, surefooted design on the African wild asses that led to their domestication by the Egyptians more than 6,000 years ago!

Grass on the menu
All wild asses are herbivores and spend their time grazing on grasses, but they will also eat scrub, bark, and tough desert plants. Wild asses at the San Diego Zoo's Wild Animal Park are fed hay, alfalfa, and carrots. Even though they are very well adapted for life in the desert, they must live near a water source and need to drink to survive. They are most active at dawn, dusk, and nighttime, when it is cool, in order to conserve energy and water. During the heat of the day they prefer to rest in the shade.

Tough food, tough life
The kiang Equus kiang is the largest of the wild asses. It is native to the high, cold habitat of the Tibetan plateau in Asia and is sometimes called the Tibetan wild ass. In this dry climate, the growing season for plants lasts only two to three months, so kiangs must eat as much vegetation as they can during that time to put on fat to last through the cold winter. They have tough, thick lips and the roof of their mouth is ridged to help them eat the tough grasses and shrubs that grow there.

Beating the heat
Onagers and kulans Equus hemionus live in harsh desert habitat, where summer temperatures can reach 120 degrees Fahrenheit (49 degrees Celsius)! They also have to deal with the problem of finding enough food to eat. They have adapted to life in the desert. They eat low-growing plants and grasses, as well as salty soil!

Inspiring cave painters
Somali wild asses Equus africanus somalicus are the smallest equids and are native to the rocky deserts of eastern Africa. Like the onagers and kulans, the Somali wild ass has to deal with extremely high temperatures. The animals will rest under any shade they can find until it cools down in the late afternoon and evening. They will graze again in the early morning hours. The African wild asses have been an important part of Africa's history. Their images have been painted in caves by ancient peoples in North Africa, and, at one time, sultans of the area ordered a man's hand cut off if he killed a wild ass.

To herd or not to herd
The Somali wild ass often lives alone due to the lack of food in the deserts where it is found. Small herds do exist, though, usually comprised of mares (adult females) and their offspring. Occasionally, larger groups will form during the wet season when food and water are more plentiful. This is also when foals are born and mating takes place. Stallions (adult males) are often solitary, and mature stallions are known to protect territories that will usually include a water source. It's good to be the only stallion around when the mares come down to the water hole for a drink!

Kiangs, kulans, and onagers live in herds that can number from five to several hundred individuals. The larger herds are made up of mares with their young and immature males and females. These herds are led by an older mare. Stallions tend to live alone or with other stallions, joing the herd only during the summer breeding season.

Bringing up baby
Stallions will often fight each other in bitter battles that include rearing and biting, all for the right to breed with the females. The mares give birth to foals about 11 months later. Wild ass foals (babies) are able to follow their mothers within a few hours after birth, and by the time they are one year old they are half grown, weaned, and no longer need their mothers.

Winter coats
Like all equids, wild asses grow long, dense winter coats to protect them from the cold. In the spring, they begin to molt, losing the hair in patches. To help the molting process along, two animals will stand side by side and head to tail, nipping at each other's sides and necks. The animals will also roll and bite and scratch at their own coats to keep their skin in good condition.

At risk
All wild equids—horses, zebras, and wild asses—are threatened. They must compete with people and livestock for food and water sources. They are hunted for food, skins, and use in traditional medicines. They can also freely interbreed with domesticated donkeys, which further threatens the species. The Somali wild ass is at critical risk, with only a few hundred left in the wild. Something as simple as a drought could be enough to wipe out the species completely. The Nubian wild ass Equus africanus africanus may be extinct in the wild already.

The San Diego Zoo participates in a Species Survival Plan (SSP) for equids to help keep these species alive and well. Our Wild Animal Park is one of only a few breeding facilities in the United States that maintains wild asses and has welcomed the births of over 25 Somali wild asses, more than any other zoo in North America. The Park devotes about 65 acres (26 hectares) to our kiangs, onagers, and Somali asses.

Click on title above for more info on the seven (7) living species of Equus;

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