The name hippopotamus, often shortened to 'hippo', is derived from the Greek word for 'river horse'. It is an apt description of the pygmy hippo, a reclusive and nocturnal mammal that spends much of its time in rivers or swamps. Being semi-aquatic, mating and giving birth may occur in water or on land.
Pygmy hippos are one of only two surviving species of the hippopotamidae family, the other being the much larger hippo. Adult pygmy hippopotamuses can reach a body length of between 1.4 and 1.6 metres, and can weigh between 245 and 275 kilogrammes.
They have short and stocky legs, a barrel-shaped body, a broad head and a large mouth. The eyes, ears and nose are located on the top of the head, enabling the species to see, smell and hear while the rest of the body is submerged in water. Pygmy hippos' ears and nostrils also pinch tightly shut when the animal dives underwater, making it easier to stay submerged. The animals' grey skin is smooth, except for bristles on the lips and tail.
To prevent their skin from cracking, the hippos moisten it regularly in water or mud. The pygmy hippo's skin also secretes a red substance, giving rise to the legend that the species sweats blood. The substance is not blood, however, and even though its function is unknown, scientists believe it may serve as an antibiotic or help block excessive sunlight.
Even though pygmy hippos spend most of their day wallowing in mud or in water, they emerge at night and venture onto land to feed. Their choice diet consists mainly of shrubs, ferns, broad-leaved plants and fruits.
Pygmy hippos give birth after a gestation period of 196 to 210 days, to a calf that swims almost immediately after birth. The young one is weaned six to eight months later.
Humans and leopards are the main threat to adult pygmy hippos, and pythons and crocodiles are reported to attack calves. Pygmy hippos are found in the forests and swamps of West Africa, primarily in Liberia, with small populations in Sierra Leone, Guinea and Ivory Coast. The Kenya Wildlife Service hosts several pygmy hippos in orphanages.