Zebra
- CLASS: Mammalia (Mammals)
- ORDER: Perissodactyla
- FAMILY: Equidae
- GENUS: Equus
- SPECIES: zebra (mountain zebra), quagga (plains zebra), grevyi (Grevy’s zebra)
- SUBSPECIES: 7
ABOUT
Despite their appearance, zebras aren’t just black and white. They are sturdy, spirited animals that are a study in contrasts: willful and playful, social and standoffish, resilient and vulnerable. Their life in a herd can be complex, yet they also find safety in numbers. They are prey for predators, but they are by no means shrinking violets when it comes to defending themselves. Read between the lines, and you’ll discover that the world of the zebra is colorful indeed!
Zebras are equids, members of the horse family. They have excellent hearing and eyesight and can run at speeds of up to 35 miles per hour (56 kilometers per hour). They also have a powerful kick that can cause serious injury to a predator, like a lion, a hyena, or an African wild dog. Usually the lead male of the herd, called a stallion, sounds the alarm if danger is spotted and stays at the back of the group to defend against predators if necessary, while the mares (females) and foals (youngsters) run away.
Zebras often trot when moving to new pastures, which is a fairly fast but easy gait for them to use over the long distances they may have to travel. Their hard hooves are designed to withstand the impact of their body weight and to run easily over rocky ground. When resting at night, zebras lie down while one stands watch to prevent an ambush.
Stripes: White with black or black with white? This is one of the most-asked questions about zebras. So what's up with the stripes? Zebras are generally thought to have white coats with black (sometimes brown) stripes. That's because if you look at most zebras, the stripes end on their belly and toward the inside of the legs, and the rest is all white. However (there had to be a catch, right?), some zebras are born with genetic variations that make them all black with white stripes, or mostly dark with the striped pattern on just part of their coats. And as it turns out, zebras have black skin underneath their hair. So it depends on how you look at it!
So, why the stripes? They serve as a kind of protection from predators! When zebras are grouped together, their combined stripes make it hard for a lion or leopard to pick out one zebra to chase. Zebra stripes are unique to each individual, and researchers in the wilderness have used zebras’ individual stripe patterns for identification.
It might seem like a zebra is a zebra, but there are three different species: plains, mountain, and Grevy’s zebras. Different zebra species have different types of stripes, from narrow to wide. In fact, the farther south on the African plains you travel, the farther apart the stripes on the zebras get! The basic form of zebras—a large head, sturdy neck, long legs, a dorsal stripe along the spine and down a tasseled tail, and bristly mane—is universal. No zebra, or other wild equid, has a forelock.
The Grevy’s zebra is the largest, weighing from 770 to 990 pounds (350 to 450 kilograms) and measuring up to 5 feet (1.5 meters) at the shoulder. Its thick neck and large, round ears give the Grevy’s zebra the most mule-like physique. The Grevy’s zebra also has the thinnest stripes, extending all the way down to their white belly; on the hindquarters the stripes are vertical until above the hind legs.
A mountain zebra has vertical stripes on the neck and torso, which graduate to wider—and fewer—horizontal bars on the haunches. It has a gridiron pattern on the rump, and its white underside has a dark stripe that runs the length of the belly. A mountain zebra also has a distinctive dewlap on the throat that looks a bit like an Adam’s apple.
The plains zebra is the most abundant and the smallest of the three zebra species. Some subspecies have a stripe pattern different from all others: brownish “shadow” stripes between the black stripes on their coat.
HABITAT AND DIET
Different zebras have different habitats: Grevy’s zebras live in semi-arid grassland habitat in Kenya, Ethiopia, and Somalia. Mountain zebras, as their name implies, inhabit rocky, arid slopes in Namibia and Angola. Plains zebras, which are the most abundant of the three zebra species, are found from the grasslands of East Africa to the scrubby woodlands of southern Africa. They are one of Africa’s most successful and adaptable large herbivores. A subspecies of the plains zebra, the Grant’s zebra, is famous for its spectacular migrations during the rainy season in the Serengeti, when as many as 10,000 of these animals can be seen journeying together in congregated herds.
Zebras are herbivores and feed mostly by grazing on grasses, although they also might browse a bit on the leaves and stems of bushes. They graze for many hours each day, using their strong front teeth to clip off the tips of the grass. Their back teeth then crush and grind the food. Spending so much time chewing wears the teeth down, so those teeth keep growing all their lives.
As the dry season arrives and the grasses die back, zebra herds travel to find more food and water holes for drinking. Most zebras are considered nomadic, without specific territories. The exception is the Grevy's zebra. Stallions of this species mark out territories with urine and dung. The mares, their foals, and immature males wander through as they wish. If food becomes scarce, though, the stallions leave their territories for a while and travel with the larger herds.
Zebras at the San Diego Zoo and the San Diego Zoo Safari Park are fed hay, alfalfa, and carrots.
FAMILY LIFE
Scratch my back and I’ll scratch yours: Plains and mountain zebras are social herd animals, living in family groups with a stallion, several mares, and their offspring. During certain times of the year, these groups gather together to form loosely associated herds of up to several hundred, but the family groups still stay together within these larger groups. Grevy’s zebras do not have a herd system, and males and females have no permanent bonds. Grevy’s zebra stallions establish territories, with mares crossing through them to breed and foal. Once the foals are old enough to travel, the mares usually leave the protection of the stallion’s territory to continue their nomadic lifestyle.
Zebras communicate with one another with facial expressions and sounds. They make loud braying or barking sounds and soft snorts and whuffs. The position of their ears, how wide open their eyes are, and whether their mouths are open or their teeth are bared all mean something. Ears flat back, for example, means trouble, or you better follow orders! Zebras also reinforce their bonds by grooming each other. You might see two zebras standing head to back, apparently biting each other, but they are really only nibbling on each other with their teeth to pull out loose hair and get a good scratch.
Like domestic horses, zebras put a good deal of energy into raising their offspring. Zebra foals have soft, fuzzy fur, and their stripes are usually brown and white at first. Their legs are already almost as long as an adult zebra’s and they can walk just 20 minutes after birth and can run after an hour! This is important, since the mare needs to move with the herd to find food and water. She cannot leave the foal behind, so it must be up and running quickly in order to stay with the family.
Foals must be able to recognize their mother from birth in order to survive. A foal learns its mother’s stripe pattern in order to follow her. Mares usually do not adopt other foals, so there would be no chance of getting food from anyone but Mom. Mothers often separate from the herd a short distance so that their foals can imprint on them. Once the foal can readily identify its mother, the mare and her foal return to the herd for protection.
CONSERVATION
There are some threats—loss of habitat, poaching, and disease—that zebras can’t outrun. With a wild population of about 25,000, the mountain zebra is classified as threatened. The Cape mountain zebra came very close to extinction as a result of hunting and competition with domestic cattle. In 1937, Mountain Zebra National Park was established in South Africa, where only 47 Cape mountain zebras remained. Their numbers have now increased to several hundred, with the majority still in the national park.
The endangered Grevy’s zebra population has been ravaged by anthrax outbreaks, dropping its ranks to an estimated wild population of 2,250. San Diego Zoo Wildlife Alliance is a member of the Grevy’s Zebra Trust, an independent wildlife conservation organization in Kenya, and our scientists are working with other conservation groups to help preserve the population. As of August 2012, we have had 128 Grevy's zebra births at our facilities.
You can help, too. Every weekend at the San Diego Zoo we offer guests an opportunity to feed our Masai giraffes for a $10 donation. The money raised goes to the Northern Rangelands Trusts in Kenya and the Grevy’s Zebra Trust, both of which have a major focus on helping zebras. Through the generosity and participation of guests at the Zoo’s giraffe feeding, donations have brought much-needed help in vaccinating zebras against anthrax in Kenya and funding other needs.
By supporting San Diego Zoo Wildlife Alliance, you are our ally in saving and protecting wildlife worldwide.