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Hippo Unna 2541



Hippopotamus amphibius

The hippopotamus is considered the most dangerous animal in Africa and are highly territorial. Hippo populations are formed under a male who controls the best habitat in the area. His territory encompasses a strip of shore and water. He gets the best territory by confronting challengers in duels that range from ritualistic display to bloody battle. Males are so ferocious that females often form their own nursery herd, or creche, to guard the calves.

Hippos form groups under a bull. He claims territory where he gathers a harem of several females and their young. To keep the females for himself, the bull will fight off any hippo that dares to come near. Hippo breeding takes place so that the gestation period, 227 to 240 days, will end when rainfall is at its peak. The female produces a single calf, which she nurses for 4-6 months. The calf is born and nursed underwater. The calf weighs about 60 to 110 pounds at birth and will weigh about 500 pounds by its first birthday. Females and their young usually have lasting relationships.

Hippos are classified as Vulnerable by the International Union for Conservation of Nature (IUCN). A more recent assessment suggests that there are likely between 115,000 to 130,000 common hippos remaining. Major threats to hippos are illegal/unregulated hunting for meat and ivory, pollution of the water, and the consumption of water by nearby cities.

What are they like?

Physical Description: Hippos range in weight from 2200 lbs to 9900 lbs with the males being significantly larger than the females. Hippos' bodies are a uniform brownish gray dorsally, paler beneath, with pinkish areas on their face. Their body is very scantily covered with short, fine hairs. The canine teeth are long and curved. The long incisors point forward in the lower jaw and downward in the upper jaw. The length of the head and body can get up to about 13 ft, and they can stand up to 5 ft tall.

Life Span: In both zoos and the wild, hippos typically live 35-50 years. The oldest hippo on record lived for over 60 years in a zoo.

Diet: In the wild, hippos graze on as much 200 pounds of grass, herbs, and leaves, typically at night. At the Zoo, our hippos eat 12 pounds of produce and four pounds of herbivore pellets, and as much hay as they want—usually around 50 pounds—is given to them daily.

Social Structure: Males can stake a claim to a stretch of territory where they will reign. There they will have a group of females and young offspring. The group can vary from only a few to about thirty of them. Hippos are individualistic and will put their own needs and the needs of their offspring before any other hippo around them. They can become very territorial in the water, too, which makes it hard for the younger ones to find their own space. There is a dominant male in the herd that is allowed to control what the females will do. They do allow some younger males to be in the herd, but only if they continue to take on a submissive role. Should those males express an interest in mating they will be driven out of the herd. Many of these males do develop an urge to mate and so they leave their herd willingly and join bachelor herds.

Habitat: Hippos are semiaquatic and require enough water to be immerse themselves in while also being close to grass. They live along the rivers and lakes throughout sub-Saharan Africa. Hippos spend most of the day in the water to stay cool and emerge before night to forage on land. At the Zoo, our hippos' habitat includes two pools—one indoors and one outdoors—as well as plenty of room on land to explore or lay down and sun themselves.

Where do they live?

Historically, hippos have been found throughout all of sub-Saharan Africa, but many populations have been reduced or exterminated. Currently, the only large populations of hippos occur in Central Africa and specifically the Nile River valley of East Africa. They are currently an invasive species in Colombia, with a very small but rapidly increasing population in the double digits.

Hippopotamus range Sub-Saharan Africa

Did you know?

  • You can tell our hippo Unna apart from Cindy by the white spots over her eyebrow and on the bottom of her chin. Unna is the more dominant of the two hippos and has a shorter temper. Cindy is the sweetie and often comes up to her keepers for petting.
  • Despite their stocky shape and short legs, hippos can easily outrun a human. They have been clocked at 19 mph over short distances.
  • Hippos secrete an oily pink substance that protects their skin from water loss and sunburn.
  • Hippos learn how to swim before they can walk and can hold their breath for 6 minutes underwater.

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