The Classification of Zebra
Scientific name: Equus grevyi
Kingdom ~ Animalia
Order ~ Perissodactyla
Family ~ Equidae
Subgenus ~ Hippotigris
The largest of the zebras, the
Grevy's can be distinguished
from the plains zebra
Weight: Males 660-320lb
300-400kg, up to 990lb (450kg
females: 595-725b 270-330kg
Height 4ft Gin-5ft (1 45-1.5m)
Length: 8ft 4in (2.55m,
plus tail: 2ft 4in (70cm)
Gestation: 12-13 months
Young: 1
Lifespan: 15-20 years.
Identification
The largest of the zebras, the Grevy's can be distinguished from the plains zebra by its large head and bat ears, its narrow, close set stripes and unstriped belly. The thin circular stripes on the rump form a distinctive 'target.
Grevy's zebras are sometimes found in mixed groups with plains zebras. The Grevy's, the largest of the zebras, is found in north-eastern Kenya and southern Ethiopia. It has large bat ears, narrow, close-set stripes and an unstriped belly.
Voice
Brays like a donkey.
Habitat
Grevy's zebra is the most northerly representative of the zebra family inhabiting the dry savanna and arid bush country of northern Kenya and southern Ethiopia.
Habits
Diurnal and nocturnal. Grevy's zebras adopt a very dilferent form of social organization to plains zebras, Groups of five to ten females and their foals wander in overlapping home ranges which include the territories of a number of ternitorial males.
Social grooming is almost absent, and herds seem to lack cohesion or well-defined social bonds. Young males stay in their mother's herd until they are three years old and then leave to join other bachelors. They are fully mature and capable of holding a territory at six years old. Stallions mark the boundaries of their territory by defecating and urinating at dungnmiddens, by calling and by their physical presence. Bachelors often mingle with the female herds while searching for good grazing, and are tolerated by territory holders as long as none of the females is in oestrus. Large mixed herds of up to 200 individuals sometimes form during the dry season migrations, and may gather at waterholes. These big herds generally disperse for the duration of the dry season to avoid competition for scarce grazing. Territorial males often remain on their territory year round, waiting for the females to return at the onset of the wet season, when most breeding takes place.
Reproduction
Foals are born throughout the yearbwith a peak during the rains. Females usually have their first foal when they are three years old. Newborn foals gain their feet within 10-15 minutes and can run within the hour. Mothers with young foals congregate in nursery herds, sometimes in the company of heavily pregnant mares and mares with older young
Food
Grevy' s zebras graze on the stems and seed heads of various grass species, browsing on herbage during the dry season when grass is in short supply. They drink daily if water is available, but can go without drinking for two or three days when necessary. During prolonged drought they will dig for water in the river beds.
The Cheif Predation
Lions prey on adults and young, while leopards and hyaenas sometimes take foals.
Grevy’s zebras—loiborkoram in the Samburu language—are massive. At up to almost a thousand pounds, they are the largest wild animals in the horse family. Their prominent ears appear rounded at a distance, and their stripes are finer than those on a regular old plains zebra. “They are absolutely stunning animals,” says Belinda Low Mackey, a cofounder of the Nairobi-based Grevy’s Zebra Trust.
They are also highly endangered. Just 2,000 adults remain in the wild, and their range has shrunk from a significant swathe of the horn of Africa to a few places in northern Kenya and just over the border into Ethiopia.
Hunting in the 20th century and ongoing competition for scarce food with livestock that also graze their arid habitat have driven their numbers down. Since 2009, the area has also suffered regular droughts, which shrivel the grass the zebras eat. Photographer Heath Holden accompanied some of the Trust’s rangers in Samburu County, Kenya, in October. The land was “unbelievably dry,” he says. “All the rivers were dry.” (Read more about threats to grasslands here.)
Combined with the overgrazing of livestock, these events can kill large numbers of Grevy’s zebras. And so the Grevy’s Zebra Trust has chosen to feed them. They’ve delivered bales of hay during droughts in 2011, 2014, 2017, and again late last year along the zebras’ routes to watering holes. The hay comes from a neighboring province with more rainfall and is bought in by truck or motorbike. In 2017, the worst drought in at least the past decade, the Trust put out more than 3,500 bales of hay.
But is it right to feed wild animals? In many cases, the answer is no. Philosopher Clare Palmer, who studies human-animal ethics at Texas A&M University, says that one could, in theory, argue that feeding the zebras reduces their wildness by making them more dependent on humans for food. And becoming dependent on people arguably makes them less free. (Read about why you shouldn't feed your backyard wildlife.)
"Reducing animals’ freedom in this sense could be seen as a kind of hubris, human arrogance in trying to control everything that goes on in the world,” she says.
Humans feeding wild animals without careful plans can cause them to become dangerously habituated to humans and change their behavior. In some cases, migrating animals have changed or given up their annual journeys; in other cases, habituated animals venture too close to humans and scare them or damage their farms and homes, risking retaliatory killings. In this case, the zebras eat the hay at night, when the humans are gone, so they don’t even see their food delivery drivers.
And when the alternative is starving to death, a small reduction in one kind of wildness is considered by Kenyan wildlife managers an acceptable price to pay for their survival. Besides, Palmer argues, the zebras’ lives have been shaped by living alongside grazers for millennia and by climate change for at least several decades. “It’s not as though there’s a living-independently-of-human-impact option for these zebras,” Palmer says. (Learn why spots and stripes aren't so black and white.)
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