Hippopotamus

Presentation

The hippopotamus is a large semi-aquatic mammal perfectly adapted to water life. With its thick, hairless skin of grey-brown color, massive body and short, sturdy limbs, it represents one of the largest living artiodactyls. Although primarily aquatic, it spends significant time on land, particularly for feeding.

The hippopotamus has a unique morphology: a massive skull with powerful molars, a mouth capable of opening over 150°, and skin secreting a reddish fluid acting as both sunscreen and lubricant. Its short legs have four webbed digits facilitating aquatic locomotion.

Characteristics

Indicative values: they vary by subspecies, sex and region.

Habitat and distribution

The hippopotamus frequents rivers, lakes, and wetlands in sub-Saharan Africa, preferring deep freshwater with accessible banks leading to grazing areas. It requires habitats with substantial vegetation cover and sufficient water depth for complete submersion.

Behaviour

The hippopotamus is a gregarious and territorial animal. Females and young live in groups of 10 to 15 individuals, while dominant males are generally solitary or defend territories. Primarily active at night, it spends the day immersed or partially immersed to stay cool. Hippopotamuses are renowned for their aggression, particularly females protecting their young.

Reproduction

Gestation in the hippopotamus lasts approximately 8 months, typically resulting in a single calf weighing 45 to 50 kg. Nursing continues for 6 to 8 months. Females are highly protective and aggressive toward any intruder threatening their calf. Sexual maturity is reached around 7-8 years for females and 10-15 years for males.

Peculiarities

The hippopotamus produces a reddish cutaneous substance called 'blood sweat' which, far from being blood, is a protective pigment acting as natural sunscreen. Its canine teeth can reach 50 cm in length. Paradoxically, this massive animal can run on land at speeds of 40 km/h over short distances and hold its breath for over 5 minutes.

Threats and conservation

The hippopotamus is classified as Vulnerable primarily due to poaching for the ivory of its teeth and loss of aquatic habitats caused by river and lake degradation. Conflicts with humans increase as populations become denser near inhabited areas. Climate change affecting hydrological cycles also threatens its habitats.

References

UICN — Liste rouge des espèces menacées

Profile updated 08 August 2026 · Reviewed by the TunisieVet editorial team.

CONSERVATION STATUS

Vulnerable (VU)

IUCN source, latest published assessment.

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