Class: Mammalia (Mammals)
Length: 4.9 to 5.7 feet (1.5 to 1.75 meters)
Height: 30 to 39 inches (75 to 100 centimeters)
Weight: 350 to 600 pounds (160 to 270 kilograms)
Life span: 35 years
Gestation: 6 to 7 months
Number of young at birth: usually 1
Weight at birth: 7.5 to 14 pounds (3.4 to 6.4 kilograms)
Age of maturity: 4 to 5 years
Conservation status: vulnerable
Common hippos give birth underwater, while pygmy
hippo calves are born on land.
A pygmy hippo calf can nurse from its mother on land or underwater.
A loud eater, the pygmy hippo can be heard munching from up to 150 feet (45 meters) away!
Pygmy hippos were unknown to Western science until about 1840.
A hippo weighs about 10 times as much as a pygmy hippo.
Mammals: Pygmy Hippopotamus
Good things come in small packages
At first glance, the pygmy hippopotamus looks like a mini version of its larger relative, the hippopotamus (also known as the river, or common, hippopotamus). But there are other differences besides size. The pygmy hippo has adaptations for living in the water but is much less aquatic than the hippo. Its nose and ears close underwater just like a hippo's do, but its head is rounder and narrower and its eyes are not on the top of its head. The pygmy hippo's feet are less webbed and its toes more free than those of the hippo, and its legs are longer than its huge cousin's. The pygmy hippo's teeth are also different: it only has one pair of incisors, while the hippo has two or three. Not only is the pygmy hippo much smaller, it is much more rare, found only in the interior forests in parts of West Africa. Little is known of its habits in the wild.
A secret life
The pygmy hippopotamus is usually solitary but can sometimes be found in small family groups. Males, called bulls, have larger territories than cows (females) and both mark their homes with their droppings. Pygmy hippos are mainly nocturnal, resting well hidden in swamps, wallows, or rivers during the heat of the day until dark, when they leave the water to feed on land for a few hours in the cool of the night. Unlike their larger relative, pygmy hippos are shy and would prefer to flee rather than stay and fight. Although they are able to make noises—from a low grunt to a high-pitched squeak—pygmy hippos are usually silent.
The top layer of the pygmy hippo's skin is smooth and thin to help the animal stay cool in the humid rain forest. However, the thin skin could cause the hippo to dehydrate quickly in the sun. That's why the hippo's skin oozes out a pink fluid that looks like beads of sweat. This fluid, called "blood sweat," helps to protect the animal's sensitive skin from sunburn. Too bad we humans don't have built-in sunscreen!
Hungry, hungry hippo
There is much more to learn about the pygmy hippo's herbivorous diet. Researchers believe that they most likely feed on roots, grasses, shoots, and fruits. Pygmy hippos search for food on the forest floor or in swamps, but can stand on their hind legs to reach food higher up in trees if they need to.
Pygmy hippo calves
When pygmy hippo cows are ready to breed, there is usually a bull waiting nearby. The breeding season in the wild is unknown but normally one calf is born on land after a gestation period of six to seven months. For the first few weeks the mother tucks the calf away in the bushes while she feeds, because the baby cannot walk well. The calf grows quickly and at 5 months of age is already about 10 times its birth weight.
Hope for hippos
Known to be found only in four countries in West Africa—Sierra Leone, Guinea, Côte D'Ivoire (Ivory Coast), and Liberia, with a suspected isolated population in Nigeria—pygmy hippos are at risk of becoming endangered. The forests that shelter them are being cut down or burned away, and the rivers where they swim are now polluted by humans. These shy animals are also hunted for their meat. Fortunately, pygmy hippos breed well in zoos; however, more protection is needed for the wild populations so that they will not vanish altogether.