Imperial zebra
Grévy's zebras (Equus grevyi) are magnificent and elegant creatures. Although they belong to the horse family, these animals are actually more closely related to the African wild asses. Due to excessive and continuous hunting, they were once threatened with total extinction. Currently, efforts are being put to recover from this huge population loss. Grévy's zebras perceive their environment through a well-developed binocular vision. When it comes to food, these mammals are very selective and require a suitable quality of food.
The Grévy's zebra is the largest of all wild equines. It is particularly mule-like in appearance; the head is large, long, and narrow with elongated nostril openings; the ears are very large, rounded, and conical and the neck is short but thick. The zebra's muzzle is ash-grey to black in colour with the lips having whiskers. The mane is tall and erect; juveniles have a mane that extends to the length of the back and shortens as they reach adulthood. As with all zebra species, the Grévy's zebra's pelage has a black and white striping pattern. The stripes are narrow and close-set, being broader on the neck, and they extend to the hooves. The belly and the area around the base of the tail lack stripes and are just white in color, which is unique to the Grévy's zebra. Foals are born with brown and white striping, with the brown stripes darkening as they grow older.
The current range of this species covers the northeastern and southern regions of Ethiopia as well as central and northern Kenya. Within this territory, Grevy’s zebras are generally found in dry, semi-desert grasslands.
Grevy's zebras are diurnal mammals. They exhibit a rather unusual social behavior for zebras. Thus, females and their young may occasionally gather in temporary herds. Within these herds, mothers and their calves live in very close bonds. On the other hand, males tend to be solitary and don't develop long-lasting relationships. Mature males display highly territorial behavior, marking their home ranges by means of "middens" - dung piles. They generally live in the same area throughout the year, although may leave the territory for greener pastures when the summer is too long. Reaching adolescence at 1-4 years old, young males leave their mothers and form bachelor herds. The male shows his dominance with an arched neck and a high-stepping gait and the least dominant males submit by extending their tails, lowering their heads and nuzzling their superior's chest or groin. Zebras produce numerous sounds and vocalisations. When alarmed, they produce deep, hoarse grunts. Whistles and squeals are also made when alarmed, during fights, when scared or in pain. Snorts may be produced when scared or as a warning. A male will bray in defense of his territory, when driving females, or keeping other males at bay. Distressed foals will squeal. To get rid of flies or parasites, they roll in dust, water or mud or, in the case of flies, they twitch their skin. They also rub against trees, rocks and other objects to get rid of irritations such as itchy skin, hair or parasites. Although Grévy's zebras do not perform mutual grooming, they do sometimes rub against a conspecific.
The diet of these herbivorous (graminivorous) mammals primarily consists of grasses, supplemented by fruits, tree bark, shrubs, roots, leaves, and buds.
These zebras have a polygynandrous (promiscuous) mating system. The female may visit as many as four territories a day and will mate with the males in them. Among territorial males, the most dominant ones control territories near water sources, which mostly attract females with dependent foals, while more subordinate males control territories away from the water with greater amounts of vegetation, which mostly attract females without dependent foals. Mating occurs at any time of year with peak periods in July-August and October-November. The gestation period lasts for 13 months, yielding a single baby, which is born highly developed. Within the first 6 minutes after birth, the foal begins to walk. It's able to run about 45 minutes after birth. During the first 6-8 months of its life, the foal is suckled by its mother, living with her for up to 3 years, when it becomes reproductively mature. However, young males begin breeding only after 6 years old.
These animals are currently facing one of the most wide-scale range reductions among African mammals. They have lost a considerable part of their original range. The remaining populations suffer from harsh competition for food with other grazing animals. They also compete for resources with cattle and livestock. On the other hand, population numbers are negatively affected by excessive grazing and competition for water sources. Those in Ethiopia are threatened by large-scale hunting for their meat, striking coats and medical use.
According to the IUCN Red List, the total population of Grevy’s zebras is 1,966 - 2,447 individuals. This includes 1838-2319 animals in Kenya and 128 animals in Ethiopia. Overall, Grevy’s zebras are classified as Endangered (EN) on the IUCN Red List but their numbers remain stable today.
Grevy's are an important source of food for numerous predators of their range (lions, cheetahs, leopards, hyenas).