Active during the day, the Peruvian spider monkey feeds on a wide variety of ripe fruits, particularly figs (Ficus), although unripe fruit, new leaves and flowers are also eaten, particularly when fruit is scarce. The diet may also be supplemented with seeds, buds, bark, wood, honey and occasionally small insects (2) (11) (12) (13) (14), and the Peruvian spider monkey is believed to be an important seed disperser (1) (12). Spider monkeys are highly agile primates, able to move swiftly through the trees by swinging, climbing, running, or walking bipedally, and can even hang suspended entirely by the tail (2) (8) (9) (10).
The Peruvian spider monkey lives in groups of up to 20 to 30 individuals, but members of the group are rarely seen together, usually splitting into smaller, temporary groups to travel, feed and rest. Each female has a core area of the group’s territory which she uses most, while males cooperate in defending the whole territory against neighbouring groups (1) (2) (10) (12) (15). Breeding may occur at any time of year, the female giving birth to a single young after a gestation period of around 226 to 232 days. Spider monkeys reproduce slowly, each female giving birth only once every two to four years, and individuals not reaching maturity until around four to five years old. When mature, young males generally remain within the group, while females leave to join another group (1) (2) (8) (10) (15). The Peruvian spider monkey has been recorded living to about 40 years (8).