| Class: | Mammalia |
| Order: | Artiodactyla |
| Family: | Hippopotamidae |
| Size: | Height: 4.3 to 5.6 feet (1.3 to 1.7 m) to shoulder Length: 10 to 16.9 feet (3 to 5.2 m) |
| Weight: | 2200 to 8000 pounds (998 to 3629 kg) |
| Diet: | Grass and plants |
| Distribution: | East Africa, south of the Sahara |
| Young: | 1 young every 2 years |
| Animal Predators: | Lions, hyenas, leopards and crocodiles prey on young |
| IUCN Status: | No special status |
| Terms: | Female: Cow Young: Calf |
| Lifespan: | 20 to 40 years in the wild, up to 50 years in captivity |
· The scientific name “Hippopotamus amphibius” means “horse who lives in and around a river” in Greek.
· Hippos can bite a 10-foot crocodile in two.
· A hippo who appears to be yawning is actually threatening and may be about to attack.
The third largest land mammal, second in weight only to the elephant and the white rhinoceros, adult hippopotamuses have no predators other than man. Because of their short legs and heavy body, hippos look as if they might be clumsy on land, but they can gallop or trot up to 20 mph (32 kph), turn swiftly and climb steep banks. They do not, however, jump and never step over an obstacle. Both male and female hippos can be extremely aggressive and their major weapon is the large, sharp lower canines which can be up to 20 inches (51 cm) long, resembling tusks. Their skin is thick and nearly hairless, gray-brown above and pink coloured underneath. Hippos secrete a sweat-like red oil that protects their skin from the sun and from drying out.
Hippos emerge from the water at dusk and begin to graze. Their diet consists entirely of grass and plants.
Mating occurs in the water, and calves are born approximately eight months later, either in water or on land. Cows isolate themselves when their time to give birth comes, and the cows and calves rejoin the herd when the young are between 10 and 44 days old. Calves, who weigh 55 to 120 pounds (25 to 54 kg) at birth, nurse both underwater and on land. In the water, calves often ride on their mothers’ backs. They begin to graze at five months and are weaned at approximately eight months. Mothers are very protective of their young and band together within the herd, even babysitting each other’s youngsters and guarding them against crocodiles and bull hippos. Groups of mothers will swarm and attack bulls who create a disturbance near the nursery herd. Calves and their mothers have an extremely close bond and female offspring especially may stay with their mothers for years.
Hippos are semi-aquatic animals who spend their days in water—swimming, diving, resting or even sleeping. The water holds their enormous weight, allowing them to relax their heavy bodies. They spend most of their time hanging in the water with only their ears, eyes and nostrils showing. When totally submerged, hippos can close their nostrils and ears and stay underneath the water for up to 30 minutes. They live in herds of 10 to 200 animals, mostly females and their offspring, and led by dominant males who battle, sometimes fatally, to be leader. They are extremely social and gregarious animals, interacting closely with their neighbours, even resting their heads on each other’s backs. While on land, hippos do not keep as closely together as in the water, focussing mainly on feeding and leaving the socializing to dawn, when they return to the waterhole. Hippos are suspicious of humans and become aggressive, overturning the boats of curious people who venture too close. An important part of the African ecosystem, hippos provide food for tiny micro organisms in the water who feed on hippo dung. Larger animals feed on the organisms. As well, with their huge bodies, hippos clear large paths through vegetation so other animals have access to rivers and lakes.
A subspecies, Hippopotamus amphibius tschadensis found in the African countries of Chad and Niger is listed by the IUCN as Vulnerable.
http://animaldiversity.ummz.umich.edu/accounts/hippopotamus/h._amphibius$narrative.html
http://www.thebigzoo.com/Animals/Hippopotamus.asp
http://www.scz.org/animals/h/hippo.html
http://sailfish.exis.net/~spook/hipptxt.html
http://www.ultimateungulate.com/riverhippo.html
http://www.hippopotamus-amphibius.com/
Great African Hippopotamus Wildlife Fact File, IM Pub, US