“Hippos can hold their breath for several minutes underwater.”
Common hippos spend hot days in African rivers and lakes, then leave the water after dark to graze on land. Their semi-aquatic life depends on access to both deep resting water and nearby grassland, while territorial males defend stretches of shoreline.
By An Nguyen · Published · Updated
Hippopotamus amphibius Artiodactyla Hippopotamidae
Measured against the 176 species profiled on this site. Each figure is converted to one unit system from the published range on the page, so the ranks are computed, not quoted.
| Measure | This species | Rank here | Exceeds |
|---|---|---|---|
| Body mass | 2 t | #9 of 176#6 of 90 Mammalia | 95% |
| Body length | 4.88 m | #14 of 176#7 of 90 Mammalia | 92% |
| Top speed | 30.6 km/h | #59 of 75#39 of 46 Mammalia | 22% |
| Lifespan in the wild | 50 yr | #19 of 169#9 of 85 Mammalia | 86% |
Closest in body mass
Ranks use the upper end of each published adult range, so they compare typical large adults rather than records, and metrics with no published number are left out rather than estimated. The full table is downloadable from the species dataset, and any two species can be put side by side in the comparison tool.
Browse photographs of hippopotamus across habitat, behavior, anatomy, and life stages.
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Core article
A closer look at habitat, diet, behavior, reproduction, and conservation.
The hippopotamus (Hippopotamus amphibius) is a large semi-aquatic mammal of the rivers, lakes, and wetlands of sub-Saharan Africa. It is the third-largest living land mammal, behind only elephants and some rhinoceroses, and despite a reputation for being sluggish it is powerful and aggressively territorial in water. Grazing on land at night and returning nutrients to the water by day, it acts as an ecosystem engineer, altering the hydrology and nutrient cycles of the waterways it occupies.
Hippos are colossally heavy, bulls larger than cows: a mature male runs 10 to 16 feet long, up to 5.5 feet at the shoulder, and 3,300 to over 4,400 pounds, yet can hit 19 mph in a short charge on land. The skull is built for amphibious life, with eyes, ears, and nostrils set high on top so the animal can see, hear, and breathe while almost fully submerged, and muscular valves that seal the ears and nostrils when it dives. The skin is up to two inches thick as armor against rival tusks, but lacks sweat glands, so hippos secrete a viscous red "blood sweat" — neither blood nor sweat, but a glandular fluid that works as sunscreen and antibacterial protection in pathogen-rich water. The jaws open to a huge 150-to-180-degree gape, revealing self-sharpening ivory canines up to 20 inches long. It belongs to the family Hippopotamidae; surprisingly, genomics shows the hippo's closest living relatives are not pigs but the cetaceans — whales and dolphins — from a common semi-aquatic ancestor around 55 million years ago.
The hippopotamus is confined to sub-Saharan Africa, once ranging from the Nile Delta to the Cape but now fragmented across countries like Kenya, Tanzania, Botswana, Zambia, and the DRC. The absolute requirement is permanent, slow-moving freshwater deep enough to submerge in — rivers, lakes, marshes, and inland deltas like the Okavango — which protects the animal's huge body from equatorial heat. But water is only half the habitat: adjacent open savanna or grassland provides the "hippo lawns" they graze at night. A pod reshapes the landscape, its weight carving deep permanent channels through reed beds that many other species then use, which is why hippos are keystone ecosystem engineers.
For all their dental weaponry, hippos are obligate herbivores, and their feeding follows a sharp daily rhythm: inactive in the water by day, they leave at dusk and trek up to several miles inland to graze the savanna. The staple is short, nutritious grass — a big adult needs 80 to 100 pounds a night — cropped close to the root by broad, muscular lips that work like a lawnmower, while the ivory canines are strictly weapons, not for eating. They don't chew cud like cattle; a massive three-chambered stomach ferments the forage efficiently. Before dawn they follow worn "hippo trails" back to the exact stretch of river.
Hippo society is shaped by territory. They gather in pods (or "bloats") of 10 to 30, sometimes over 100 in a severe dry season, usually a dominant bull with cows and young; bachelor males may stay if they don't challenge him. The bull defends a stretch of deep water — a few hundred yards — and marks it by "muck-spreading," spinning his tail while defecating to fling scent about. Aggression is common: challenges begin with jaw-gaping displays and can escalate to combat with the canines that causes serious or fatal wounds, and hippos will attack crocodiles, lions, or people in small boats they see as threats.
Reproduction is tied to the water — mating happens submerged, and after about 8 months' gestation the female isolates herself in a quiet shallow or reed bed to give birth, remarkably, underwater. The newborn must kick straight to the surface for its first breath; precocial at 50 to 100 pounds, it can swim and walk almost at once. Maternal investment is high and fiercely protective — the mother attacks any threat, including bulls that may commit infanticide in crowded conditions — and the calf even nurses underwater, sealing ears, nostrils, and lips to keep water out. It stays dependent for about 18 months, gradually shifting to grass. In the wild hippos that survive youth live 40 to 50 years.
The hippopotamus is Vulnerable with a decreasing global trend; it remains numerous in protected strongholds in East and Southern Africa but faces mounting pressure. The biggest threat is loss and degradation of its specialized freshwater habitat, as expanding human populations divert rivers and wetlands for irrigation and dams — drying up hippo habitat and forcing the animals into violent conflict with communities as they raid crops. Poaching adds to it: hippos are killed for bushmeat, and their canine teeth enter the illegal ivory trade as an elephant-ivory substitute. Conservation centers on protecting freshwater habitat, reducing human–wildlife conflict, and enforcing restrictions on illegal hunting and ivory trafficking.
Kingdom
Animalia
Phylum
Chordata
Class
Order
Artiodactyla
Family
Hippopotamidae
Genus
Hippopotamus
Species
H. amphibius
Hippos can hold their breath for several minutes underwater.
Despite living in water, hippos cannot swim—they push off the bottom or walk.
Hippo sweat looks reddish and may help protect their skin from sun and germs.
A hippo's mouth can open nearly 180 degrees during a threat display.
Hippos graze for hours at night and may eat more than 80 pounds of grass.
Baby hippos are born underwater and must swim to the surface to breathe.
Select a question to reveal the answer.
Wild hippos live in rivers, lakes, and wetlands across sub-Saharan Africa. They need deep water for daytime resting and nearby grassland for feeding.
Hippos are herbivores that mainly eat grass. They leave the water at night to graze on land.
Yes. Hippos are unpredictable and very strong. They can charge boats or people who get too close, especially on land or near calves.
Water keeps their huge bodies cool under the hot African sun and helps protect them from biting insects and some predators.
Hippos are listed as Vulnerable. Hunting and habitat loss have reduced their numbers in many countries.
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