Zebras in Turmoil: Africa's Painted Horses Symbolize Conservation Dilemmas on a Changing Environment

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Early in the nineteenth century, the first Europeans to penetrate the interior of southern Africa found one animal that literally glittered on the sun-swept plains. This was the quagga, a type of zebra with chestnut body, white legs and tail, and cinnamon and cream stripes on head, neck and chest. One British hunter of the 1840s wrote that quaggas at a distance sparkled like mica.

Named for its barking call, the quagga roamed South Africa by the thousands. However, as Europeans moved in, they killed quaggas mercilessly, using the hides for commerce and the meat for feeding servants. The last quagga died in the Amsterdam Zoo in 1883.

Ecologists, taxonomists, geneticists and wildlife managers are struggling today to prevent two jeopardized species of zebra, the mountain and the Grevy's, from also going the way of the quagga. In addition, these scientists are endeavoring to ensure that the plains zebra, the only zebra species not facing immediate jeopardy, maintains its foothold on survival even as burgeoning human populations overrun wildlife habitat.

A Trio of Painted Ponies. Africa's three zebra species look much alike. The mountain zebra is the only slight eccentric, $ince it alone among zebras bears a loose fold of skin, called a dewlap, along its throat. Otherwise, all three fit a pattern-basic horse body with black and white stripes. The stripes vary in detail from one type of zebra to the next, but to the untrained eye the differences are minimal.

Grevy's zebra, with the narrowest stripes, is the largest member of the horse family. Large specimens weigh in at up to 450 kilograms (1,000 lbs.). The Grevy's lives in semi-arid scrub and grassland in northern Kenya and south-central Ethiopia. Also native to Somalia, it has not been seen there since 1973, and biologists believe it is extinct in that part of its range.

Mountain zebras, the smallest at 200 kilograms (440 lbs.), occur in isolated populations in southwestern Africa. They prefer broken or mountainous country but also live on plateaus and flats, including the edges of deserts and in semiarid and savannah grasslands.

The five subspecies of ponylike plains zebras, which average about 250 kilograms (550 lbs.), range across the savannas and grasslands of eastern and southern Africa.

Zebras are generalized herbivores. They prefer grasses, but when pressed for food will eat the more digestible parts of trees and shrubs. Although the zebra's dietary adaptability may make it stiff competition for less flexible species such as antelope and cattle, under most conditions the zebra benefits other wild grazers.

Biologist Richard Bell, working at the Serengeti Research Institute in Tanzania, found that during July and August, when hundreds of thousands of animals move from Tanzania's Serengeti plains to Kenya's Masai Mara National Reserve, zebras go first, followed by wildebeest and then gazelles. Zebras clear off the tops of tall coarse grasses, too difficult for other herbivores to digest. Wildebeest eat the shorter, more digestible blades of grass. And Thomson's gazelles, which require the highest protein content of all, nibble the shortest plants and new sprouts.

Zebras have another important nutritional role: They serve as food for a variety of predators and scavengers. They are the most important prey species for Serengeti lions and rank second only to wildebeest as the kill of choice among the lions and hyenas of Tanzania's Ngorongoro Crater. Zebras are the biological foundation upon which the predators stand.

Life in the Social Club. Hans and Ute Klingel, of the University of Braunschweig in Gennany, began their zebra research in the 1960s in Tanzania and Kenya, becoming the first biologists to look at a herd of plains zebras and see something other than a field of stripes. The herds, they found, are composed of hundreds of individual families, each consisting of one male with one to six females and offspring. …