Hippopotamus (Hippopotamus amphibius)

 

Family:                    Hippopotamidae.

Status:                     Protected by CITES.

Size:                        10 to 15 ft. long, 5 to 5.4 ft height to shoulder, 2200 – 8000 lbs.

Diet:                        Herbivore.

Characteristics:        Sociable, aggressive.

Area:                       Africa.

Offspring:                One young every two years.

Predators:               Lions, hyenas, leopards and crocodiles prey on young.

 

Trivia:

·       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.

·       Hippos have wide, muscular lips to pluck grass and don’t use their teeth at all for eating.

 

Lifestyle

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 stay underneath the water for up to five minutes or more. They’re extremely social and gregarious animals, interacting closely with their neighbours, even resting their heads on each other’s backs. At dusk, they emerge and begin to graze, their diet consisting entirely of grass and plants. While on land, the hippos don’t keep as closely together as in the water, focussing mainly on feeding and leaving the socializing to dawn, when they return to the waterhole. The second largest land mammal, second in weight only to the elephant, an adult hippopotamus has no predators other than man. Because of their short legs and heavy bodies, hippos look as if they might be clumsy on land, but they can gallop or trot up to 18 mph, turn swiftly and climb steep banks. They don’t, 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 1.5 feet 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 are suspicious of humans and become aggressive, overturning the boats of curious people who venture too close.

 

Territory

Hippos stay close to water, never going more than 2 to 6 miles away from water while grazing. At one time, they lived all over Africa but now are extinct in the northern and southern parts of the original range. The only large populations of hippos currently exist in East Africa, especially in Ethiopia, Kenya, Sudan, Tanzania, Uganda. They live in herds of 10 to 150 animals, mostly females and their offspring, and led by dominant males who battle, sometimes fatally, to be leader. 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, powerful mouths, hippos keep large areas of grass trimmed which keeps paths clear so other animals have access to rivers and lakes. The trimmed grass also helps keep dangerous grassfires to a minimum.

 

Reproduction

Mating occurs in the water, and calves are born eight months later, either in water or on land. The cow will isolate herself when her time to give birth comes, and she and the calf rejoin the herd when the baby is between 10 and 40 days old. The calf, who weighs 55 to 110 pounds at birth, nurses both underwater and on land. In the water, the baby often rides on the mother’s back. They begin to graze at 5 months and are weaned at 8 months. Mothers are very protective of their children 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. Babies and their mothers have an extremely close bond and female offspring especially may stay with their mothers for years, helping to take care of their younger siblings. The lifespan of a hippo is 30 to 40 years in the wild, or up to 50 years in captivity.