Please be advised that on April 25 at Franklin Park Zoo and April 26 at Stone Zoo, we will be conducting a routine animal escape drill. These drills are an important part of our preparedness training. While the drill is occurring, guests will be asked to move to certain areas within the Zoo for a brief period of time (not to exceed 10 minutes). We will do our best to have minimal impact on the guest experience. We are very dedicated to safety and we appreciate your participation. If you have any questions about what to expect, please do not hesitate to contact us at 617-989-2000 or



Hydrochoerus hydrochaeris


About the Capybara


Geographic Range:


Class: Mammalia  
Order: Rodentia  
Family: Caviidae
Genus: Hydrochoerus  
Species: hydrochaeris

Capybaras are widely known as the world's largest rodent. They're very good swimmers, which is helpful in their Amazon rainforest habitat. Their nostrils have adapted over time to sit high on the snout, enabling them to breathe when swimming under water. Capybaras feed on dense vegetation in the rainforest and have become more active at night due to human activity.

Capybara Facts

The capybara is the largest rodent in the world. Its body is heavy and barrel-shaped. Its head is short and its skull resembles that of a guinea pig, except that it’s considerably larger and more robust. On the dorsal (upper) side, the fur is reddish brown and yellowish brown on the belly. Occasionally, they have some black on the face, outer limbs and rump. Each of its toes is tipped with a hoof-like claw with webbing connecting the digits. Their external ears and eyes are small and with the nostrils sit high up on the head; as a result, when they’re in water, only their nostrils, eyes and ears are visible. Male capybaras have a distinctive scent gland that they brush against grass to mark their territories. These "morrillos" appear as dark, oval-shaped, hairless bumps on their snouts.

Length up to 130 centimeters (more than 4 feet)
Height 50 centimeters (1.6 feet)
Weight 60 to 170 pounds

Mostly grasses and aquatic plants.

The capybara reaches sexual maturity at 18 months and breeds between April and May.  Gestation lasts 149-156 days and usually results in one to eight young. Capybaras mate in the water. A female will usually have one litter per year.

Capybaras are active in the morning and evening and rest during the heat of the day in a shallow burrow. They become increasingly nocturnal in areas populated by humans. They’re social and live in groups of variable sizes. Several groups may come together in the dry season around a watering hole.

The smaller sub-groups are controlled by a dominant male. The dominant male, usually the heaviest, stares down other males in the group, driving them to the outer edges of the group. Subordinate males act as lookouts, giving warning barks when predators approach. Vocal animals, capybaras communicate through purrs, squeals, grunts, barks and whistles.

It’s important that capybaras have a constant source of water available in which to hide from predators. When threatened, they’ll run like a horse, and when a predator is close, the capybara will enter the water.

Densely vegetated areas around ponds, lakes, rivers, streams, marshes and swamps in Central and South America.

Median Life Expectancy:
Males: 7.1

Females: 8.6

Jaguars; additional predators may include anacondas and caimans.

Fun Facts:

  • Capybaras are related to guinea pigs.
  • They are the largest of all the rodents.