Social Organization

Capybaras are known to be gregarious. While they sometimes live solitarily, they are more commonly found in groups of around 10 to 20 individuals, with two to four adult males, four to seven adult females, and the remainder juveniles.

Female mating

When in estrus, the female's scent changes subtly and nearby males begin pursuit. In addition, a female alerts males she is in estrus by whistling through her nose. During mating, the female has the advantage and mating choice. Capybaras mate only in water, and if a female does not want to mate with a certain male, she either submerges or leaves the water.

Babybaras

Capybara gestation is 130 to 150 days, and produces a litter of four young on average, but may produce between one and eight in a single litter. Birth is on land and the female rejoins the group within a few hours of delivering the newborn capybaras, which join the group as soon as they are mobile. Within a week, the young can eat grass, but continue to suckle—from any female in the group—until weaned around 16 weeks. The young form a group within the main group.