Central American Spider Monkey

Geoffroy's spider monkey is one of the largest New World monkeys. Its arms are about a quarter longer than its legs, the thumb is only a vestige, and the long hooked fingers let it swing beneath branches. The strong prehensile tail ends in a bare pad and works as a fifth limb, able to carry the whole animal's weight. Colour varies from buff or reddish to brown or black, with dark hands and feet and usually a pale mask around the eyes and muzzle (Wikipedia, general species account; Handbook of the Mammals of the World).

It is arboreal and diurnal and mostly keeps to the upper forest, although it comes to the ground more often than other spider monkeys. The monkeys live in fission–fusion societies of about 16–42 animals that split into subgroups of two to six to forage, and a group's range can exceed 900 ha. Males are dominant and patrol the home-range edge; females disperse from their natal group. At Santa Rosa National Park, daily movement averaged about 1.3 km, and many births occur in the dry season (GBIF species profile).

The species depends on large areas of intact forest. On this guide it is a target species of Tortuguero, Braulio Carrillo, Guanacaste National Park and Corcovado.