Pygmy Hippopotamus

Institute for Breeding Rare and Endangered African Mammals

Pygmy hippos are endangered because their West African forest habitat is shrinking at an alarming rate, primarily due to human endeavors. It’s estimated that just a few thousand of these elusive, secretive animals survive in the wild, and that number might be high. Zoo New England is proud to be working on two fronts to ensure the survival of these rare hippos.

Zoo New England participates in the Pygmy Hippo Species Survival Plan (SSP), a consortium of AZA (Association of Zoos and Aquariums) accredited institutions working to preserve sustainable captive populations, thereby preventing pygmy hippo extinction. Zoo New England also supports the first in-depth study of wild pygmy hippos, which will provide valuable information about how to improve the well-being of pygmy hippos in zoos.


The pygmy hippopotamus (Choeropsis liberiensis) is native to certain West African rainforest areas in the countries of Sierra Leone, Guinea, the Ivory Coast and Liberia. The pygmy hippopotamus is considered endangered due to its shrinking natural habitat, the result of logging, farming and human settlement. The pygmy hippo is also increasingly falling prey to bush hunters as rainforests become smaller and more accessible to people.

The pygmy hippo was declared an endangered species by the International Union for Conservation of Nature (IUCN) in 2006. Because of their reclusive nature, they are difficult to count, and currently there's no accurate count of wild pygmy hippos. In 1993, IUCN put the number at approximately 2,000-3,000.

The small North American captive population consists of about 80 individuals, including Cleopatra and Inocencio, Franklin Park Zoo’s two pygmy hippos (more on this pair below).

Adult pygmy hippos weigh between 400-600 pounds. They grow to about 5 feet long and stand a stout 2.5 to 3.5 feet tall. Exclusively vegetarian, they forage for leaves, roots and fallen fruit on the forest floor in the dark of night. Pygmy hippos spend most of the day hidden in rivers, resting in the same spot for several days before moving to a new location. They are solitary animals, living alone or in pairs, usually a mother and calf or a mated pair.

In the field: A hippo named Franklin

Zoo New England has supported the Institute for Breeding Rare and Endangered African Mammals’ (IBREAM) Pygmy Hippo Project, the first large and in-depth study of a free-ranging pygmy hippo population. Little is known about the day-to-day existence of pygmy hippos due to their solitary, nocturnal habits, so this is truly groundbreaking work. IBREAM researchers working in Tai National Park in the Ivory Coast of West Africa attached GPS devices to pygmy hippos to study hippos' foraging behavior, nutrition, reproductive behavior, denning requirements, diving behavior, and the effects of human disturbance on these behaviors. This research will hopefully improve the way we provide for the well-being of our captive pygmy hippos. One of the hippos in the research group is named Franklin, after Franklin Park Zoo! We’re proud to have our name associated with this pioneering research.

Pygmy hippos at Franklin Park Zoo

Here at home, we’re hoping that Cleopatra will breed with her companion Inocencio (In-o-sen-si-o), who made his debut in February 2014. This pairing is the result of a recommendation by the AZA Pygmy Hippo SSP, which aims to maintain a genetically diverse and demographically stable captive population of pygmy hippos.

In December 2013 veterinarians, wildlife and customs officials, and Zoo New England staff were on hand to greet Inocencio when his plane touched down at John F. Kennedy International Airport in New York. He then traveled with Zoo staff to his new home at Franklin Park Zoo, arriving just in time for the holidays and his second birthday on December 28. Inocencio was imported from the Parque Zoologico Buin Zoo in Chile where he was born. In compliance with laws and regulations governing humane treatment, great care was taken to ensure Inocencio arrived in good health and with proper importation documents.

After a month-long quarantine in Franklin Park Zoo hospital, Inocencio joined pygmy hippo, Cleopatra, in the Zoo’s Tropical Forest exhibit. Cleopatra also came to the Franklin Park Zoo through an international collaboration, in this case with the Toronto Zoo in 2007. The North American captive pygmy hippo population is very small in number and highly skewed toward females, so Inocencio is crucial to the effort to create a self-sustaining population.

Be sure to visit the Tropical Forest exhibit and look for Inocencio snacking on romaine lettuce or pushing his boomer ball (one of the Zoo’s many animal enrichment items) through the water! He and Cleopatra trade time in their exhibit.

For more on pygmy hippos, visit our Franklin Park Zoo Animals page.