The hippopotamus is one of the most recognizable and somewhat paradoxical mammals in the world. With a mass of over 3.5 tons, it has a barrel shaped figure, stubby stocky legs, a colossal head and extraordinary set of tusk-like canines. 

It’s biological title Hippopotamus amphibius, is an indirect Greek translation for River Horse; though it is neither a horse nor a creature famed for its land-based finesse. These river tanks are the third largest land mammal after Elephants and White Rhinos. They, like other mammals of their size, are found across sub-Saharan African countries including Tanzania, Botswana,  Zimbabwe and Uganda, where large bodies of slow moving water are available. Routinely, they appear rotund and unhurried; however these remarkable creatures are capable of short bursts of surprising speed, both above and beneath the surface, making them the fastest mammal above 2.25 tons. Their presence is crucial in shaping African River ecosystems, as their grazing, dung, and movement between water and land contribute to nutrient cycles.

Hippo Habitats

Water sources such as lakes, rivers and swamps are primarily a Hippo's habitat, giving them not only a refuge from the intense African Sun, but also a base from which they can access neighbouring grasslands for feeding. Water is critical — hippos can hold their breath for several minutes, but prolonged sun exposure without immersion can lead to dehydration and overheating. 

Standout locations for Hippos include the Selous and Ruaha reserves in southern Tanzania, particularly in the dry season when water sources shrink, concentrating wildlife. Here, riverbanks are often lined with dozens of Hippo’s jostling for space. The best times to see hippos are early in the morning and late in the afternoon. During these times, they might be grazing near the shore or moving between feeding areas and the water. 

Behaviour & Diet

Hippos are frequently active after sunset when they emerge from the water to graze on short grasses, often travelling miles to do so. Their eating technique is particularly unfamiliar involving their strong lips clipping short grasses, as opposed to them using their monumental teeth to bite. So why do these creatures have such formidable teeth? Their 20-inch-long tusks and powerful jaw strength is purely for fighting and display during clashes for dominance. 

Pods are led by one dominant male who defends a stretch of river. Territorial disputes and conflicts are violent, with deep grunting, open-mouth displays and occasional fights. 

Females give birth in the water, usually to one calf after an eight-month gestation. The calf suckles both on land and underwater, whilst staying close to its mother for protection. Hippo calves face threats from crocodiles, lions, and, occasionally, aggression from other hippos. In the wild, a hippos lifespans averages 40 to 50 years.

Hippo Blood Sweat

Hippopotamuses have an extraordinary adaptation called “blood sweat”, which involves them secreting an orange, oily solution through exocrine glands on their skin. Hence the name, this solution gives the impression of oozing blood, particularly in the sunlight. It serves two crucial purposes: first, it acts as a natural sunscreen, protecting them from the harsh UV of East Africa. It also has antimicrobial properties, which help prevent any infections from frequent cuts and scrapes sustained during fights. It enables them to spend long hours basking near the surface without their sensitive skin drying out or burning.

Threats to Hippos & Conservation

Generally, Hippos avoid human confrontation; however they can be extremely dangerous if they feel as though they’re being threatened, especially in the water. Historically, they’ve provided meat, hides and ivory from their teeth, leading to significant declines in populations due to hunting. Today, this remains a major threat, as well as habitat loss and conflict with farmers. 

In numerous parts of Africa, wetlands are drained for agricultural purposes, and human expansion has brought settlements closer to Hippopotamus territory. Since hippos require constant access to water, reduced river flow resulting from dams and irrigation has had a noticeable effect on their population. 

They are classified as Vulnerable on the IUCN Red List, and their populations are dropping in several areas. Conservation efforts include anti-poaching patrols, community-based wetland management, and the establishment of protected areas.