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Wildlife Guide · Kenya & Tanzania

Hippopotamus

Hippopotamus amphibius

Africa's deadliest large herbivore, a semi-aquatic giant facing habitat loss and tooth-ivory trade.

IUCN: Vulnerable
A large common hippopotamus standing in a shallow African river with only its eyes, ears and nostrils above the waterline, its broad pink-grey snout and bulky body partly submerged.

Source: Wikimedia Commons via Wikipedia “Hippopotamus”

In brief

The hippopotamus (Hippopotamus amphibius) is a large semi-aquatic African mammal listed as Vulnerable by the IUCN, with roughly 115,000-130,000 individuals remaining and a declining population driven by habitat loss and demand for its tooth ivory.

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By WARN Research & Conservation TeamLast updated

The common hippopotamus (Hippopotamus amphibius) is a massive, barrel-shaped mammal that spends its days submerged in African rivers and lakes and emerges at night to graze on grass. Despite a placid appearance, it is widely regarded as one of the most dangerous large animals to people in Africa, fiercely defending its water and young. Listed as Vulnerable by the IUCN, the hippo is squeezed by shrinking and drying wetlands, conflict with farmers, and demand for its large canine teeth, which are traded as a form of ivory. This guide explains where hippos live, how they behave, why they matter, and what threatens their future.

115,000-130,000

Estimated wild population (IUCN)

Vulnerable

IUCN Red List status (2017)

Up to ~1,500 kg

Typical adult weight

40-50 yrs

Lifespan in the wild

Figures sourced from IUCN Red List: Hippopotamus amphibius, Wikipedia: Hippopotamus, CITES: Hippopotamus amphibius listing and other references on this page.

Hippopotamus: Quick Facts

Vital statistics and key facts about the Hippopotamus
Lifespan 40-50 years in the wild
Weight Roughly 1,300-1,500 kg, large bulls heavier
Body length About 2.9-5 m including tail
Diet Herbivore, mainly grass
Gestation About 8 months
Young Usually a single calf
Baby name Calf
Group name Pod (also bloat or herd)
Top speed Up to about 30 km/h on land (short bursts)
CITES Appendix II

Scientific Classification

Scientific classification of the Hippopotamus
Kingdom Animalia
Phylum Chordata
Class Mammalia
Order Artiodactyla
Family Hippopotamidae
Genus Hippopotamus
Species Hippopotamus amphibius

Conservation Status

IUCN Status
Vulnerable
Population
Approximately 115,000-130,000 mature individuals
Trend
Decreasing
Assessed
2017
CITES
Appendix II

Population trends vary by country, with some range-state populations stable or increasing while others decline; the species was assessed as having dropped by at least 30% over three generations.

Did you know?

Hippos secrete a reddish, oily fluid often called "blood sweat" that is not blood at all - it acts as a natural sunscreen and antibiotic for their bare skin.

Key Facts: Hippopotamus

  • Hippos are semi-aquatic: they rest in water by day to stay cool and protect their skin, then graze grass on land at night.
  • The IUCN lists the species as Vulnerable, with an estimated 115,000-130,000 individuals and an overall declining trend.
  • Hippos are highly territorial in water and account for many human deaths in Africa each year, making them genuinely dangerous to approach.
  • Major threats are habitat loss from wetland drainage and drought, conflict with farmers, and trade in their large canine teeth as a substitute ivory.
  • They are listed on CITES Appendix II, which regulates international trade in hippos and their parts.
  • A single calf is born after about an eight-month gestation, often nursed and even born in the water.

What is a hippopotamus and where does it live?

The common hippopotamus is a large, mostly hairless mammal in the family Hippopotamidae, distantly related to whales and dolphins. Adults can weigh well over a tonne, with bulls sometimes exceeding 1,500 kg. Hippos inhabit rivers, lakes, swamps and seasonal wetlands across sub-Saharan Africa, including protected areas in Kenya and Tanzania. They need permanent water deep enough to submerge in and open grassland nearby for grazing. During the day they cluster in pods that can number from a handful to more than a hundred animals, surfacing to breathe roughly every few minutes.


Behaviour: semi-aquatic life and why hippos are dangerous

Hippos spend up to sixteen hours a day in or near water, which keeps their sensitive skin from drying out and protects them from the heat. At dusk they leave the water and may walk several kilometres to graze, eating mainly grass. Bulls defend stretches of water and will charge boats, people or other animals that intrude, while cows are intensely protective of calves. Their enormous canine teeth, powerful jaws and surprising speed on land make encounters dangerous, and hippos are responsible for a significant number of human fatalities in Africa each year. They are best observed from a safe distance and never between a hippo and the water.


Conservation status and threats

The IUCN classifies the hippopotamus as Vulnerable, citing an overall population decline. The clearest pressures are loss and degradation of wetland habitat through drainage, agriculture and drought, which can leave hippos stranded or in conflict with people. Hippos are also killed for their meat and for their large canine teeth, which are carved and traded as a form of ivory; this trade is regulated under CITES Appendix II. Because populations vary widely between countries, conservation depends on protecting water catchments, maintaining wildlife corridors, and curbing illegal hunting and trade.

Common hippopotamus vs pygmy hippopotamus

Common hippopotamus vs pygmy hippopotamus
FeatureCommon hippopotamusPygmy hippopotamus
Scientific nameHippopotamus amphibiusChoeropsis liberiensis
IUCN statusVulnerableEndangered
Adult weightAround 1,300-1,500 kgAround 180-275 kg
HabitatOpen rivers, lakes and grasslandForests, swamps and streams
RangeSub-Saharan Africa (incl. Kenya, Tanzania)West Africa (e.g. Liberia)
Social lifeLives in pods, very territorialMostly solitary and secretive

What WARN Does

This guide is educational reference content created to improve global public understanding of the hippopotamus and the wetland habitats it depends on. The hippopotamus lives in Africa and falls outside the countries where the World Animal Rescue Network currently funds hands-on rescue and care work, so WARN does not run or fund hippo projects at this launch stage. We publish accurate, searchable species guides like this one to support WARN's broader mission of raising awareness for threatened wildlife worldwide and to help readers connect to the conservation themes - habitat protection and the fight against wildlife trade - that WARN does support directly in its funded regions.

Hippos depend on healthy rivers and wetlands - the same kind of habitats WARN works to protect in its funded regions. While WARN does not yet fund projects in Africa, your gift to Support Habitat Protection strengthens the wider effort to safeguard wild places and the species that rely on them.

How can I help save the hippopotamus?

Explore practical ways to support the hippopotamus, from everyday choices and sharing reliable information to reviewing a related appeal before giving.

1

Explore ways to support

Read the related appeal’s purpose, recipient status and fund terms. Choose an affordable gift after checking what is proposed and what has been reported.

2

Ease the pressures

Avoid the wildlife trade and souvenirs, never buy wild animals as pets, and choose sustainable, habitat-friendly products — the threats behind the hippopotamus's decline fall when demand does.

3

Spread the word

Share accurate, sourced information about the hippopotamus. Wider awareness is what turns concern into lasting protection.

Hippopotamus: Frequently Asked Questions

How can I help save the hippopotamus?

You can help the hippopotamus by supporting responsible welfare and habitat protection, avoiding wildlife exploitation and sharing reliable information. Read the related appeal’s purpose, recipient status and funding terms before donating. The page’s sources explain the species and its threats; grant records provide separate evidence of funded work.

Is the hippopotamus endangered?

Not endangered, but threatened. The IUCN classifies the common hippopotamus as Vulnerable, one step below Endangered, with an estimated 115,000-130,000 individuals and a declining overall trend driven by habitat loss and hunting for meat and teeth.

How many hippos are left in the world?

The IUCN estimates roughly 115,000 to 130,000 common hippos remain in the wild across sub-Saharan Africa. Numbers vary considerably between countries, with some populations stable and others falling.

Are hippos dangerous to humans?

Yes. Hippos are highly territorial and aggressive in defending water and young, and they are considered among the most dangerous large animals to people in Africa, causing many human deaths each year. They can also move quickly on land despite their size.

What do hippos eat?

Hippos are herbivores that feed almost entirely on grass. They leave the water at night and graze on land, consuming only small amounts of aquatic plants. An adult eats tens of kilograms of vegetation in a single night.

Can hippos swim?

Hippos are semi-aquatic but do not truly swim. In deep water they move by pushing off the bottom and gliding, and they can stay submerged for several minutes, surfacing to breathe. Calves can even be born and nurse in the water.

Why are hippos hunted?

Hippos are killed for their meat, in conflict with farmers, and for their large canine teeth, which are carved and traded as a substitute for elephant ivory. International trade in hippos and their parts is regulated under CITES Appendix II.

Where do common hippopotamuses live?

Common hippopotamuses are native to sub-Saharan Africa, in suitable rivers, lakes and wetlands with nearby feeding areas. Kenya and Tanzania are examples within this wider range, which extends across parts of West, Central, East and Southern Africa. They are not confined to those two countries.

How long do common hippopotamus live?

Common Hippopotamus typically live 40-50 years in the wild. The hippopotamus (Hippopotamus amphibius) is a large semi-aquatic African mammal listed as Vulnerable by the IUCN, with roughly 115,000-130,000 individuals remaining and a declining population driven by habitat loss and demand for its tooth ivory. Wild and captive figures can differ; use the sources listed on the guide for the underlying studies.

How big is a common hippopotamus?

The IUCN SSC Hippo Specialist Group gives average adult weights of approximately 1,550 kg for males and 1,385 kg for females, with average head-and-body lengths around 3.1 m and 3.0 m respectively. These are reference averages, not maximum sizes; individuals vary with sex, age and condition. The smaller pygmy hippo is a different species.

Terms used on this page

Plain-English definitions, from our wildlife and conservation glossary.

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