Of the two species of hippopotamus, only one, the pygmy hippopotamus (Choeropsis liberiensis) is classified as endangered. A pygmy hippo looks much like the better-known common hippo, but smaller, with eyes on the side of a more rounded head. Although little is known about this nocturnal species, a 1993 International Union for Conservation of Nature study, the most recent of its kind, estimated between 2,000 and 3,000 individuals live in the West African countries of Liberia, Sierra Leone, Guinea and the Ivory Coast. Conservation biologists consider a Nigerian pygmy hippopotamus subspecies to be extinct.
Unlike many animals, pygmy hippos breed easily in captivity, and international captive breeding programs for the species have been successful. As of 2004, the most recent count, 303 pygmy hippos lived in captivity, 209 of which were captive-born. This represented more than twice the number of captive-born pygmy hippos since 1970. Many of these were born from parents who also had been bred in captivity. Captive breeding faces challenges because much of pygmy hippo behavior in the wild is unknown, causing some to die in captivity. For example, although wild individuals live in solitude, coming together only to mate, many captives are kept in pairs, causing hostility.
The biggest threat to the pygmy hippopotamus' continued survival is loss of habitat due to logging and deforestation to clear the way for agricultural development and human settlements. Because of this, the species' largest populations are found on protected nature preserves. A large population lives in the Sapo National Park in Liberia, the country's only national preserve. The park's 509 square miles are the most effectively protected pygmy hippopotamus habitat according to the IUCN. Pygmy hippo populations also live in Tai National Park in the Ivory Coast and the Gola Forest Reserve in Sierra Leone.
National and International Law
Pygmy hippos enjoy full legal protection in all of the countries where they live, as well as from the Convention on International Trade in Endangered Species of Wild Flora and Fauna treaty, which prohibits trade in threatened or endangered species. In Liberia, for example, they're included in the country's 1988 Wildlife and National Park Act. National legislation also exists to ban hunting and logging or clearing of critical habitat. However, due to extensive conflict and civil unrest in the region, coupled with a lack of resources, these laws are poorly enforced and don't provide as much protection for pygmy hippos as is needed if the species is to rebound.
Research and Education
In 2009, the IUCN Hippo Specialist Group established a subgroup to study and document populations of the species so recovery plans could be tailored to better meet the animal's needs. Surveys were conducted using camera traps to better estimate the size of populations and observe their behavior. As a result of these efforts, a previously unknown pygmy hippo population was discovered in 2011 in Sierra Leone. Conservationists also work with local populations, emphasizing the uniqueness of the species and advocating an end to hunting for the bush meat or trophy markets. Former hunters assist in conservation programs designed to provide alternative sources of income for hunters who want to stop.
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