New World Monkeys

There are two species of squirrel monkeys, the smallest of the New World monkeys. The common squirrel monkey (Saimiri sciureus) lives throughout most of South America's rain forest region. The red-backed squirrel monkey (S. oerstedii) occurs only in Panama and Costa Rica in the middle levels of the forest, where they eat primarily fruit, though they also use their narrow, sharply pointed teeth to devour small insects. Some authorities regard the red-backed squirrel monkey as a subspecies of the common squirrel monkey.

The common squirrel monkey is the species often kept as a pet. Its thick, short fur is gray, the chest is white, its legs are yellow, and it has white circles around its eyes, giving it a widow's peak above the nose. A large dark oval of bare skin encircles the nose and mouth on the muzzle.

Squirrel monkeys do not have a prehensile tail, and all swinging on branches is done with their arms, while their tails tend to rest curled over their shoulder. The tail is considerably longer than their 12 in (30 cm) body.

Squirrel monkey groups vary from 20 animals up to 200 individuals. When such a large group takes over a tree, the other cebid species, even the larger ones, are overwhelmed and forced to leave. The large squirrel monkey social group has very complex social relationships among individuals and subgroups. Some subgroups consist only of males, who remain by themselves except during mating season. This precludes a male from taking care of its single offspring, unlike most of the species of New World monkeys. The mother monkey's female friends may help raise and care for an infant. A single infant squirrel monkey is born after a gestation period that varies from 152-172 days. It becomes independent at about a year and sexually matures at three years for females and five for males. Squirrel monkeys have been known to live almost 15 years.

In the 1960s, the red-backed squirrel monkey was imported into the United States by the thousands for use as pets. Capture for the pet trade together with the destruction of their habitat of rain forest has severely endangered the wild populations of this monkey. Today, the United States government has outlawed the importation of primates except for legitimate scientific purposes.