Capybaras are huge grazing rodents, which live in herds and are semi-aquatic.

Life span
About 6 years (up to 12 in captivity).

Statistics
106-134cm long, 50 to 62cm at the shoulder. Males weigh 35-64kg, females 37-66kg.

Physical description
Heavily built animals which look rather like pigs covered in reddish brown hair. They have no tail, their front legs are slightly shorter than their back legs, with slightly webbed feet. Their muzzles are blunt, with the eyes, small ears and nostrils all placed on the top of their head.

Distribution
South America east of the Andes from Venezuela to Northern Argentina. A second population (sometimes classified as a separate species, Hydrochaeris isthmius) is found from North West Venezuela through North Colombia up to the Panama Canal.

Habitat
Flooded savannah and grassland, and along rivers in tropical forest.

Diet
Grass.

Behaviour
Capybaras live in groups of 10-30, although they can form looser aggregations of up to 100 individuals. There is usually one dominant male per group (with a prominent scent gland on his nose), with a few females and their offspring plus a number of subordinate males. They communicate through scent and barking noises. In the mornings the animals usually rest, eating their own faeces in order to help digest the tough cellulose in the grass. During the midday heat they wallow in the water to keep cool and then graze in the late afternoon and early evening. They never sleep for long, spending much of the night grazing, and only doze throughout the day and night.

Reproduction
Capybaras reach sexual maturity at about 18 months and breed whenever the conditions are appropriate (once per year in Brazil, and throughout the year in Venezuela/Colombia). The male pursues a receptive female until she stops in the water, allowing him to mount. Gestation is 150 days, and then a litter of about 4 (but up to seven) well-developed young are born. The female seeks a covered area on land to give birth and rejoins the group a few hours after the birth, joined by the young whenever they are mobile. The young can eat grass within a week, but suckle from different females within the group for longer, moving in a group creche of youngsters.

Conservation status
Although they are not currently listed by the IUCN, their numbers dropped dramatically due to hunting in the 1980s. Since protection they have stabilised.

Voice
Capybaras are vocal animals emitting purrs and alarm barks.

Records
The largest rodents, although there were extinct capybaras weighing eight times as much - larger than a grizzly bear!