Are Hippos Endangered?

Both species of hippo face dwindling populations in the wild

Hippopotamus In River

Nick Dale / Getty Images

While the common hippo (Hippopotamus amphibious) is categorized as vulnerable, its smaller relative, the pygmy hippo (Choeropsis liberiensis or Hexaprotodon liberiensis), does have a place on the endangered species list. Both species continue to be threatened by illegal hunting and shrinking habitats.

Common Hippo

The much larger common hippo, listed as vulnerable since 2008, experienced significant declines throughout the mid 1990s and into the early 2000s. These giants can be found throughout sub-Saharan Africa, where they live in rivers and lakes during the day and wander onto shore at night, in search of grass and fruit to munch on.

With their huge size and affinity for water, it's no wonder why the hippo earned its nickname “water horse.” Interestingly, scientists have found that the hippo is most closely related to cetaceans (whales, dolphins, and porpoises). Studies have shown the evolutionary connection between hippos and cetaceans by comparing how both species adapted to aquatic living, most notably through their respiratory tracts (external nostrils, or blowholes in the case of whales).

Estimates from the Red List Assessment puts current common hippo populations at about 115,000﹣130,000, down from 125,000﹣148,000 in 2008. This downward spike was not enough to change the animal’s risk category, though, due to possible miscounts from certain countries in 2008. However, the evaluation still states that hippos' conservation status is "precarious," and direct conservation action to protect hippos and their habitat remains a priority. Although hippo populations have stabilized in a handful of countries, declines have been reported in many locations because of habitat loss and unregulated hunting.

Pygmy Hippo

Grazes (eats) on green grass
Pygmy hippo grazes on grass. MikhailSemenov / Getty Images

Pygmy hippos, which joined the endangered species list in 2010, have shown a significant decrease in numbers. Sadly, there are only an estimated 2,000﹣2,499 mature individuals left. Evidence from cameras and sign surveys in countries like Liberia continues to show small numbers, and large sections of the pygmy hippo’s original forest habitat has already been destroyed by commercial palm oil plantations, agriculture, mining, and logging. It's estimated that, due to this forest loss and increased hunting activity, pygmy hippos will see a continuing decline of about 20% over the next 26 years.

Threats

While you may be all too familiar with images of common hippos lounging in rivers and lakes, the smaller — and dare we say, cuter — pygmy hippo spends much less time in the water. This adaptivity to life on land is, perhaps to their detriment, making them more susceptible to poachers.

Habitat Loss

Large scale development around wetland areas and water diversion for agricultural purposes have caused extreme habitat loss for hippos. While common hippos have their largest populations in East Africa, they are found in at least 29 different countries, half of which have documented considerable population declines. The amphibious common hippo requires access to a permanent body of water to keep its hide moist, so it faces additional challenges as drought and development erase rivers and lakes in favor of dams, farms, and urban areas.

The biggest threat to the pygmy hippo is deforestation. Along with their forests continually being logged, farmed, settled, and converted to rubber, coffee, and palm oil plantations, an increase in mining and mining infrastructure development has poised additional threats in recent years. The little forest remaining within the pygmy hippo’s historical range has been fragmented, leaving them isolated from possible mates and susceptible to hunters. Drought and other ecosystem modifications due to climate change and severe weather, as is the case with the common hippo, tack on additional threats.

Poaching

Pygmy hippos face more challenges from hunting as the forests in their range have seen a larger uptick in logging, farming, and settlement throughout the past century, making it much easier for poachers to find them.

Both species have large lower canine incisors that, along with their meat, attracts illegal hunting and trapping. Both the common hippo and the pygmy hippo are used by humans as a source of food and for making jewelry or other handicrafts. Although pygmy hippos are not targeted as much for subsistence hunting since their teeth are of less value, they are often taken by hunters opportunistically for their meat. Many of pygmy hippo body parts, like the skull, are sometimes used in rituals or traditional medicine in certain countries as well.

Human Conflict

As more and more wetlands and forests are eliminated for farmland and housing, both species are often forced to overflow their natural grazing areas into human-occupied territory. In response, threatened farmers have been known to kill hippos to protect their land.

What We Can Do

Land and water protections are in place in regions of the world where hippos live. Many of these regulations, while considered efficient on the official level, are poorly enforced due to lack of financial resources and training. Some countries report finding hippos well outside of regulated areas, too, which makes it difficult to keep them safe. While pygmy hippos have shown breeding success in captivity, there have been few to no successful reintroductions into the wild.

Some of the best conservation efforts in place are achieved through engaging local communities and creating protected spaces. The African Wildlife Foundation, for example, helps communities minimize human-hippo conflict by building enclosures, fences, and ditches to keep grazing hippos off agricultural land. This is just one treatment for a symptom of a much larger issue, however. Preserving both species of hippo starts with creating protected spaces and strengthening already-established hippo habitats. Things like providing funding to hippo conservation efforts and research, improving national park infrastructure, and supporting national and international laws that protect hippos are all critical. Individuals can support hippos by signing petitions that protect critical habitats in African parks and wildlife sanctuaries, or by adopting a hippo (symbolically) with the World Wildlife Fund.

View Article Sources
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  2. Conway, April L., et al. “Local Awareness of and Attitudes towards the Pygmy HippopotamusChoeropsis Liberiensisin the Moa River Island Complex, Sierra Leone.” Oryx, vol. 49, no. 3, July 2015, pp. 550–558., doi:10.1017/s003060531300077x