Mammals
Okapi
Okapia johnstoni · also called forest giraffe, Congolese giraffe, African unicorn
The okapi looks like an animal designed by committee — the body of a horse, the striped legs of a zebra, the sloping back of an antelope, and the long dark tongue and skin-covered horns of a giraffe. It is, in fact, the giraffe’s only living relative, and it stayed hidden in the Congo rainforest until the twentieth century.
Overview
Okapis live only in the dense tropical rainforest of the northeastern Democratic Republic of the Congo, principally the Ituri Forest. They are solitary and elusive, each holding a home range that it marks with scent and moving quietly along established paths, browsing as it goes. They are most active by day, resting in cover, and they are so well camouflaged and so silent (to us) that they are rarely seen even where they are relatively common.
A giraffe for the forest
Everything about the okapi is a giraffe adapted for life among trees rather than above them:
- A shorter neck, suited to browsing forest understorey rather than tall acacias.
- The long, blue-black, prehensile tongue — up to 30 cm — used to strip leaves and buds and to clean its own eyes and ears.
- Ossicones — the skin-covered horns of the giraffe family — present as short knobs in males.
- Striped legs and rump, which break up the animal’s outline in the shafting light of the rainforest and give a calf a clear pattern to follow.
Okapis also have large, mobile ears and use infrasound to communicate over distance in thick vegetation.
Diet
The okapi is a selective browser, eating the leaves, shoots, and fruit of around a hundred forest plants, including some that are toxic to other animals, plus fungi. It regularly visits riverbeds to eat clay, which supplies minerals and may help neutralise plant toxins.
Reproduction
A female gives birth to a single calf after a 14–15 month pregnancy, in a hidden nest on the forest floor. The calf “lies up” — staying still and silent in cover — for its first weeks, not defecating during that time so as to leave no scent for predators, while the mother returns to nurse it. Calves are weaned at around six months.
Threats and conservation
The okapi is Endangered and declining. Its whole range lies in a conflict zone, and it faces poaching for meat and skins (some by armed militias), habitat loss from logging and artisanal mining for gold and coltan, and the breakdown of protection where the state has no control. The Okapi Wildlife Reserve and the Ituri Forest are the species’ stronghold, and its future depends on keeping those protected areas functioning, supporting the rangers who patrol them, and working with the Mbuti and other forest communities.
Okapi: common questions
Is the okapi related to the zebra?
No — the leg stripes are misleading. The okapi is the giraffe's only living relative; the two are the sole members of the family Giraffidae. An okapi looks like a cross between a horse, a zebra, and a deer, but its skull, ossicone "horns" (in males), teeth, cloven hooves, and long dark tongue are all giraffe features on a shorter-necked, forest-adapted body. The stripes evolved for camouflage in the broken light of the rainforest and to help a calf follow its mother, and have nothing to do with zebras.
Why was the okapi discovered so late?
It lives in one of the most remote and difficult rainforests on Earth, it is solitary, silent to human ears, and superbly camouflaged, and the local Mbuti people knew it but it was not described by Western science until 1901. Explorers had heard rumours of a "forest donkey" or "African unicorn," and Harry Johnston obtained skins and a skull that revealed it as a new large mammal and, to everyone's surprise, a relative of the giraffe.
How do okapis communicate if they are so quiet?
In several ways humans miss. They produce infrasonic calls — low-frequency sounds below the range of human hearing — that carry through dense forest, which mothers and calves use to stay in contact. They also leave scent trails from glands between the toes of each foot, and mark vegetation. Combined with their solitary, spread-out lifestyle, this lets okapis avoid one another and find mates without the vocal repertoire of a herd animal.
Why is the okapi endangered?
Its entire range is in the northeastern Democratic Republic of the Congo, a region beset by armed conflict, and the pressures on it are severe — bushmeat and skin poaching (including by armed groups), illegal logging and gold and coltan mining that clear and fragment the forest, and the collapse of law enforcement in insecure areas. In 2012 a militia attacked the headquarters of the Okapi Wildlife Reserve, killing staff and all 14 captive okapis. Conservation depends on protecting the Ituri Forest and supporting the reserve's rangers.