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Hydrochaeris hydrochaeris

Fascinating Facts

Weighing up to 154 pounds and reaching four feet long, it’s the world’s largest rodent.
This rodent is well adapted for swimming. Its toes are webbed and its nostrils, eyes and ears are at the top of its head so they protrude out of the water.
Excellent swimmers, they can dive and swim underwater for a considerable distance.

Physical Characteristics

Puente al Sur (Bridge to the South)

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The capybara is the largest living member of the rodents. Resembling a giant guinea pig, it has a long, coarse but sparsely haired coat which is generally reddish brown to grayish on upper parts, yellowish brown on under parts and occasionally black on the face. The front legs are shorter than rear legs; the four toes on the front feet and three on the back feet are slightly webbed and have short, strong claws.

The head is relatively large and broad, with short, rounded ears. The muzzle is heavy and squared at the end, with an enlarged upper lip. Its nostrils, eyes and ears are at the top of its head so they protrude out of the water when swimming.

In the mature male, a bare raised area on top of the snout contains greatly enlarged sebaceous glands to produce odorous secretions. The dominant male is often recognized by his large scent gland.


They are always found near water from Panama to Northeast Argentina, east of the Andes. Herbivorous grazers, they eat grasses and aquatic plants.

Their incisors are large, white and shallowly grooved to allow them to eat very short grasses. The cheek teeth grow continuously. They have a non-perpendicular jaw hinge and grind back and forth rather than side to side.

Social Behavior

An alarm bark is given by the first member of a group to detect a predator. This coughing sound is often repeated several times and the reaction of nearby animals may be to stand alert or rush into the water.

In the wet season, capybaras live in groups of up to 40 animals, but 10 is the average adult group size. A typical group is comprised of a dominant male, one or more females, several infants and young and one or more subordinate males. Solitary males attempt to insinuate themselves into a group but are rebuffed by the group males. Among the males, there is a hierarchy of dominance maintained by aggressive interactions which consist mainly of simple chases. The anal secretions of males and females provide a means of individual recognition via each personal "olfactory fingerprint."

When a female becomes sexually receptive, a male will start a sexual pursuit which may last for an hour or more. The female will walk in and out of the water, repeatedly pausing while the male follows closely behind. Mating takes place in the water. The female stops and the male clambers onto her back, sometimes pushing her underwater with his weight. Copulation lasts only a few seconds, but each sexual pursuit involves several mountings.

Up to seven babies are born; four is the average litter size. To give birth, the female leaves her group and walks to nearby cover. The young are born a few hours later, precocial and able to eat grass within their first week. A few hours after the birth, the mother rejoins her group. The young follow as soon as they become mobile, three or four days later. Young appear to suckle from any lactating female. Infants and young constantly emit a guttural purr. The young in a group spend most of their time within a tight-knit crèche, moving among nursing females.

Status In The Wild

They are not threatened at present. Because of the demand for capybara meat and leather, a management plan has been devised in Columbia and Venezuela for licensed ranches.


At the Zoo, you can find our pair of capybaras at Puente al Sur (Bridge to the South), an exhibit located on the north side of the Zoo near the Little Puffer train station.