ZEBRA




Most of us are familiar with the magnificent zebra, however there are actually three species of zebras alive today - the plains zebra, the Grévy's zebra and the mountain zebra. The plains zebra and the mountain zebra belong to the subgenus Hippotigris, but Grevy's zebra is the sole species of subgenus Dolichopus.

It is the unique stripes of zebras make these animals among the most familiar to people. They occur in a variety of habitats, such as grasslands, Savannas, woodlands, thorny scrublands, mountains, and coastal hills. However, various factors have had a severe impact on zebra populations, in particular hunting for skins and habitat destruction. The Grevy's zebra and the mountain zebra are endangered, but the plains zebras are much more plentiful.

One subspecies, the quagga, went extinct in the late 19th century, though they have now been re-bred from zebra DNA.

What do Zebras eat?

Food and foraging Zebras feed almost entirely on grasses, but may occasionally eat shrubs, herbs, twigs, leaves and bark.

Their digestive systems allow them to subsist on diets of lower nutritional quality than that necessary for other herbivores.

Typically, zebras seek green pastures. During the dry months of the year, they thrive on dry grass, but Zebras tend to remain in the proximity of water holes.

Zebras have a large appetite so they spend almost 60% of the time of their day eating. In zoos, they are fed hay, oats and alfalfa.


Breeding

Female zebras mature earlier than the males, and a mare may have her first foal by the age of three. Males are not able to breed until the age of five or six. Mares may give birth to one foal every twelve months. She nurses the foal for up to a year. Like horses, zebras are able to stand, walk and suckle shortly after they are born.

A zebra foal is brown and white instead of black and white at birth. Plains and mountain zebra foals are protected by their mothers, as well as the head stallion and the other mares in their group. Grevy's zebra foals have only their mother as a regular protector, since, as Grevy's zebra groups often disband after a few months.

 Where do Zebras live?

Grevy’s zebras are essentially confined to the semi-desert of northern Kenya east of the Great Rift Valley and north of the Tana River. Their range extends into neighbouring parts of Ethiopia and Somalia. During the rainy season mature stallions establish territories onto which mares come to foal and probably to breed.

Gestation is thirteen months, longer than any other equid. Once the foals are born, the mares stay within two kilometres (1.2 mi.) of water and are almost always with the territorial stallion. Foals do not drink water until they are three months olds and — unlike any other equid — are left in “kindergartens” frequently guarded by the territorial male while their mothers go to water.


The plains zebra is the most abundant and widespread of wild zebras that still exist today. They occur throughout the tropical grasslands of East and southern Africa. Zebras - for the most part - replace one another geographically. However, there is a zone of overlap between the Grevy’s zebra and the plains zebra on the floodplain of the Ewaso Nyiro in northern Kenya. Here the two species form mixed grazing herds, but there is no record of interbreeding.

The Chapman’s zebra or the Damara zebra (Equus burchelli antiquorum) is a subspecies of plains zebra occurring from Angola and Namibia across northern South Africa to Transvaal. It is characterized by a pattern of broad, dark stripes alternating with thin, light shadow-stripes. The stripes fade into the brownish color of the body on the hindquarters and are absent altogether on the legs.

Another southern subspecies of the plains zebra, the Burchell’s zebra (Equus burchelli burchelli), now extinct, lacked stripes on the hindquarters.

Its basic body color was reddish-yellow. Burchell’s zebra existed from southern Botswana into the Orange Free State of South Africa.

 As European settlement spread northward from the Cape to colonial Southern Rhodesia, this subspecies was hunted to extinction. The wild herds had disappeared by 1910, and the last known individual died in the Berlin Zoo in 1918.

The southernmost subspecies, the quagga (Equus burchelli quagga) of South Africa, is also extinct. It occurred in large numbers south of the Orange River at the beginning of the nineteenth century, but Boer settlers destroyed the population for meat and hides.

The quagga disappeared from the wild by 1878, and the last zoo specimen died in 1883. All that remains today are nineteen pelts, a few skulls, three photographs and a few paintings.

The quagga was yellowish-brown with stripes that were confined to the head, neck and forebody. DNA from one of the pelts has been retrieved and analysed, establishing that the quagga was, indeed, a variant of the plains zebra and not a separate species as previously believed. There is currently an experimental breeding program in progress in South Africa to try to reconstruct the quagga from the Chapman’s subspecies.

The third zebra species is the mountain zebra. The most identifying feature of both mountain zebra subspecies is a square flap of skin or dewlap on the throat, best developed on males.

Mountain zebras never form the large herds characteristic of plains zebras, but do exhibit a harem-type social system. During the winter they move up to twenty kilometres (12 mi.) from a water source. Where they are hunted, they take their water at night. Where they are unmolested, they water at any time.

Two subspecies of mountain zebra are recognized - the Hartmann’s zebra and the Cape mountain zebra.  The Hartmann’s zebra (Equus zebra hartmanni) occupies the rugged, broken terrain at the edge of the African Plateau east of the Namib Desert. Its habitat grades from an open woodland with a diverse, grassy under-story in southern Angola and Namibia to the succulent steppe of the Karroo in South Africa.

In the 1950's, mountain zebras numbered between 50,000 and 75,000 and were regarded as vermin by an expanding livestock industry. Especially in drought years, zebras competed with cattle for forage and water, and stampeding zebras occasionally tore down fences. By 1960 only 10,000 were left; and in 1973 Hartmann’s zebra was considered an endangered species, with approximately 7,000 head remaining.

Hartmann’s zebras have broad black stripes on an off-white body. The stripes extend down the legs to narrow hooves, but do not meet on the belly. These animals stand from 118 to 132 centimetres (46-52 in.) high. This subspecies seeks shade and rests during the hottest parts of the day and has been demonstrated to orient its body with respect to the sun. The vocalizations of the Hartmann’s zebra are similar to the neigh of a horse.

The Cape mountain zebra (Equus zebra zebra) is the smallest of the extant zebras — with a shoulder height of about 120 centimetres (47 in.) — and the most restricted geographically. Its broad black stripes are closely spaced on a pure white body. Overall it is stockier than the Hartmann’s zebra, has longer ears, and has a larger dewlap.

The Cape mountain zebra once inhabited all the mountain ranges of the southern Cape Province of South Africa, but by 1922, only 400 were believed to survive. To counteract the continued decline, Mountain Zebra National Park was established in 1937 on acacia veld near Cradock, South Africa, but its small population of Cape mountain zebra became extinct in 1950. That same year reintroductions from nearby remnant populations began. Eleven animals were donated from a nearby farm in 1950, and in 1964 another small herd was added. By the late 1960's, the total Cape mountain population was only 140 but grew to 200 by 1979, with 75 percent of the animals in Mountain Zebra National Park. In 1984, the population was back to 400 head. Since then a few zebras have been reintroduced to the Cape Point Nature Reserve.

For related articles click onto the following links:
ARE ZEBRAS BLACK WITH WHITE STRIPES OR WHITE WITH BLACK STRIPES?
CAN ZEBRAS BREED WITH HORSES?
ZEBRA

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