Swahili Name: Punda Milia
Scientific Name: Burchell’s zebra (Equus burchellii); Grevy’s zebra (Equus grevyi)
Size: 45 to 55 inches at the shoulder (Burchell’s); 50 to 60 inches (Grevy’s)
Weight: Burchell’s: 485 to 550 pounds (Burchell’s); 770 to 990 pounds (Grevy’s)
Lifespan: 40 years in captivity
Habitat: Woodlands to open plains
Diet: Herbivores Gestation: 12 months (Burchell’s); 13 months (Grevy’s)
Predators: Lions, hyenas, hunting dogs, leopards, cheetahs
Zebras, horses and wild asses are all
equids, long-lived animals that move quickly for their large size and
have teeth built for grinding and cropping grass. Zebras have horselike
bodies, but their manes are made of short, erect hair, their tails are
tufted at the tip and their coats are striped.
Three species of zebra still occur in
Africa, two of which are found in East Africa. The most numerous and
widespread species in the east is Burchell’s, also known as the common
or plains zebra. The other is Grevy’s zebra, named for Jules Grevy, a
president of France in the 1880s who received one from Abyssinia as a
gift, and now found mostly in northern Kenya. (The third species, Equus
zebra, is the mountain zebra, found in southern and southwestern
Africa.)
Physical Characteristics
The long-legged Grevy’s zebra, the
biggest of the wild equids, is taller and heavier than the Burchell’s,
with a massive head and large ears.
Zebras have shiny coats that dissipate
over 70 percent of incoming heat, and some scientists believe the
stripes help the animals withstand intense solar radiation. The black
and white stripes are a form of camouflage called disruptive coloration
that breaks up the outline of the body. Although the pattern is visible
during daytime, at dawn or in the evening when their predators are most
active, zebras look indistinct and may confuse predators by distorting
true distance.
The stripes on Grevy’s zebras are more
numerous and narrow than those of the plains zebra and do not extend to
the belly. In all zebra species, the stripes on the forequarters form a
triangular pattern; Grevy’s have a similar pattern on the hindquarters,
while others have a slanted or horizontal pattern.
Habitat
Burchell’s zebras inhabit savannas, from
treeless grasslands to open woodlands; they sometimes occur in tens of
thousands in migratory herds on the Serengeti plains. Grevy’s zebras are
now mainly restricted to parts of northern Kenya. Although they are
adapted to semi-arid conditions and require less water than other zebra
species, these zebras compete with domestic livestock for water and have
suffered heavy poaching for their meat and skins.
Behavior
Family groups are stable members
maintaining strong bonds over many years. Mutual grooming, where zebras
stand together and nibble the hair on each other’s neck and back, helps
develop and preserve these bonds. Family members look out for one
another if one becomes separated from the rest, the others search for
it. The group adjusts its traveling pace to accommodate the old and the
weak.
The females within a family observe a
strict hierarchical system. A dominant mare always leads the group,
while others follow her in single file, each with their foals directly
behind them. The lowest- ranking mare is the last in line. Although the
stallion is the dominant member of the family, he operates outside the
system and has no special place in the line.
Diet
Zebras are avid grazers. Both Burchell’s
and Grevy’s zebras are in constant search of green pastures. In the dry
season, they can live on coarse, dry grass only if they are within a
short distance (usually no farther than 20 miles away) of water holes.
Caring for the Young
When a foal is born the mother keeps all
other zebras (even the members of her family) away from it for 2 or 3
days, until it learns to recognize her by sight, voice and smell.
While all foals have a close association
with their mothers, the male foals are also close to their fathers. They
leave their group on their own accord between the ages of 1 and 4 years
to join an all-male bachelor group until they are strong enough to head
a family.
Predators
Zebras are important prey for lions and
hyenas, and to a lesser extent for hunting dogs, leopards and cheetahs.
When a family group is attacked, the members form a semicircle, face the
predator and watch it, ready to bite or strike should the attack
continue. If one of the family is injured the rest will often encircle
it to protect it from further attack.
