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By Deborah Ciszek
Geographic Range
In southeastern Africa, from southern Ethiopia in the north to eastern South Africa in the south, and at one point extending west as far as Angola.
Habitat
Burchell's zebras graze mainly in open, short-grass savanna. They can tolerate somewhat tall grass and sparsely wooded conditions, however, which gives them a greater geographical range than many of the other African grazing animals. Zebras therefore tend to be the first species to utilize an area, and they are followed by wildebeests and gazelles after they have trampled and cropped the grass short. At night, however, zebras stay in areas with shorter grass, and one of the group is awake at all times on the lookout for predators, which use tall grass and trees as cover.
Terrestrial Biomes:
savanna or grassland
.
Physical Description
(638 to 748 lbs)
Male and female zebras are very similar in appearance. Shoulder height is about 1.4 meters. Males usually have thicker necks than females. Burchell's zebras can be distinguished from mountain zebras by the possession of "shadow stripes" on the back and hindquarters, and the absence of a dewlap. Zebras' striping patterns are very variable. In some areas of Africa (especially near the equator) the stripes are bold and cover the whole body. In other regions stripes are lighter or absent on the belly and lower legs. No two zebras have identical striping patterns, a fact which makes individual identification convenient for researchers.
Some key physical features:
endothermic
; bilateral symmetry
.
Reproduction
A stallion determines a female's estral status by sniffing her urine. Gestation requires about 370 days. A single foal, weighing about 30 kg, is produced. If the female is in good condition she may become pregnant again almost immediately, during what is called the "foal heat." Otherwise the interbirth interval is two years. Foals can be born at any time throughout the year, but there is definitely a peak in birth rate early in the rainy season, in December and January. Newborns are able to stand on their own within 15 minutes of birth, and they begin suckling within an hour. A mother keeps all group members, including her previous offspring, away from herself and the foal for several days, but after this time social contact between the foal and the other zebras may begin. Predation by lions and spotted hyaenas results in a high juvenile mortality rate despite the fact that a mother will actively defend her young. The foal nurses for about a year. Sexual maturity occurs at about 3 years of age, but a male may not be able to defend his mating access to a group of females until he is 6 or more years old. A female begins to exhibit behavioral estrus at about 2 years of age. She may be "abducted" from her father's herd by an unrelated stallion, and possibly subsequently by others before she actually becomes old enough to reproduce. After producing a foal, her periods of estrus are more difficult to detect, and she remains with the father of her offspring.
Key reproductive features:
gonochoric/gonochoristic/dioecious (sexes separate); sexual
.
Behavior
Burchell's zebras are social. They live in permanent small family groups made up of a stallion and one to several mares and their foals. There is a dominance hierarchy among the females in the group, with the stallion's first mate at the apex and his most recently acquired filly at the bottom. Bachelor stallions may live singly or in non-familial groups. Group size varies with the quality of the local habitat. Breeding males do not allow other males to mate with the mares, and they defend their family group from predators by biting and kicking. Zebras have been known to kill hyaenas with a kick. One of the adult mares (usually the oldest) has the important task of leading the family as they move between areas in order to maintain proximity to available drinking water. Many family groups can come together to form a herd, and herds of zebras often graze in association with herds of other species, such as wildebeests. This grouping of large numbers of animals is protective because it lowers the odds that any particular individual will become the target of a predator.
Key behaviors:
motile
.
Food Habits
Zebras are grazers, eating over 50 different species of grasses. They also occasionally browse, taking herbs, leaves, and twigs. They use their agile lips to push the vegetation between their incisors, which they then snip off. The plants are ground between their powerful jaws, which move side to side as well as back to front. They particularly prefer new growth of grasses, such as is found after a burn.
Economic Importance for Humans: Positive
Zebras have beautiful and unique striped hides, which have historically been a valuable commodity. Zebras have also been used for food. Probably their most important current economic impact, however, is on the tourism industry. They are a mainstay attraction for guided tours and safaris.
Conservation Status
Historically, Burchell's zebras had a much broader distribution than they do today; currently they are generally found only in protected areas such as preserves and parks. Agricultural development and competition for habitat with domestic livestock have vastly reduced their natural habitat, and zebras have been hunted both for their hides and for food.
Other Comments
Burchell's zebras will mate with donkeys, producing a hybrid that has been called a "zebdonk." The function of the zebra's trademark stripes is still a matter of controversy. It is possible that under certain light conditions they provide camouflage. It is also possible that the patterns make it difficult for a predator to single out an individual against the backdrop of a whole herd. Neither of these explanations has been shown to be true, however, and the zebra's stripes remain a mystery.
Contributors
Deborah Ciszek (author), University of Michigan.





