White-faced sakis live high up in trees. They feed during the daytime. Although they do occasionally leap from tree to tree, sakis are not the most agile of monkeys. They climb down trunks backwards and generally run along thick branches on all fours. Sometimes, however, sakis have been seen walking on their hind legs with their arms held above their heads.
A lot of white-faced saki’s diet consists of vegetable matter and fruit. However, these monkeys do also catch small vertebrate animals, such as birds and bats. The sakis rip their victims apart with their hands before skinning and eating the pieces of flesh. The monkeys have sharp teeth that are useful for biting into forest fruits and slicing up meat.
Only male white-faced sakis have the white faces after which they are named. The females have black or dark brown faces. Most saki monkeys have broad, round faces with hooded eyebrows.
A white-faced saki group is based around a pair of breeding adults. The rest of the group, which may contain up to five individuals, will generally be the chief pair’s offspring of different ages. The breeding pair produces a single baby once a year. Most births occur in the dry season at the end of the year.
Distribution: Northern South America from Venezuela to north-eastern Brazil.
Habitat: Tropical forest.
Food: Fruit, honey, leaves, mice, bats and birds.
Size: 30 - 70 cm (12 - 27.5 in); 0.7 - 1.7 kg (1.5 - 3.75 lb).
Maturity: 2 - 3 years.
Breeding: Single young born in the dry season, which remains with its parents until it is mature.
Life span: 14 years.
White-nosed Bearded Saki
Size: 38 - 42 cm (15 - 16.5 in); 2 - 3 kg (4.5 - 6.5 lb).
This species lives south of the Amazon River in central Brazil. The white-nosed bearded saki inhabits a range of forests, and is mainly found in the emergent layer, where tall trees poke out above the upper forest canopy. This bearded saki is diurnal and rests in the boughs of trees at night. To avoid being attacked by predators, it never sleeps in the same place for two consecutive nights. The body is covered by black hair, except for the nose and upper lip, which have white fur. When a mature female is ready to mate, her vulva becomes bright red as a signal to males. Matings usually take place in December and June, with the female producing a single young each year. White-faced sakis live in large troops of up to 30 monkeys. They communicate with whistles and chirps.
Range: N. South America to Brazil.
Size: 40 - 51 cm (16 - 20 in); 2 - 4 kg (4.5 - 8.75 lb).
The black-bearded saki has a long, thick beard on its elongated chin. Its head, beard and tail are black, while its shoulders, back, hands and feet are reddish-brown to black. The tail is thick and heavily furred. White-faced sakis lives in Guyana, Venezuela and Brazil north of the Amazon. The black-bearded saki eats fruit, the seeds of unripe fruit, leaves, flowers and a few insects. It lives in troops of up to 30 individuals. The monkey's tail is non-prehensile, but the animal is capable of a very strong grip with its hands and feet. It often hangs by a single limb while foraging high in the trees.
Little is known of the habits of white-faced saki in the wild other than that it lives in large trees and feeds mainly on fruit. It requires many square kilometres of undisturbed habitat for successful breeding, however, and the widespread felling of primary forest poses a threat to its long-term survival.