The squirrel monkey is found only in Panama and the Pacific lowlands and southern part of Costa Rica.

The squirrel monkey is mostly a greenish yellow color, with a white throat, face, and ears and a black muzzle and tail tip. The undersides of its limbs are white or yellow, and it has a long prehensile tail.

Squirrel monkeys keep in groups which vary widely in size depending on the carrying capacity of their habitat: some troops are as small as 7 to 8, and others as large as 100 (these have been sighted in the Amazon basin). Several adult males will join in a single troop, and there are usually four adult females for every male. Females will have a single baby at a time after a 165-day gestation period.

This diurnal monkey has the most restricted range of Costa Rican primates, although it is very similar to and may be same species as Saimiri sciureus, another squirrel monkey which lives in Amazonian portions of Brazil, Colombia, Ecuador, Peru, Bolivia, Venezuela, and Guyanas.

Squirrel monkeys feed on insects, fruits, and sometimes leaves.

An adult female head and body length averages 28 cm, males 30 cm; the tail is longer than the body, generally 35 to 43 cm. Adult females weigh 0.5 to 0.75 kg, and males weigh 0.7 to 1.1 kg.

Order: Primates
Family: Cebidae

Eisenberg, John. Mammals of the Neotropics, Vol. 1. The University of Chicago Press: Chicago, 1989.

Janzen, Daniel H. Costa Rican Natural History. Chicago: University of Chicago Press, 1983.

Wilson, D. E. in Janzen, Daniel H. Costa Rican Natural History. Chicago: University of Chicago Press, 1983.

Amy Strieter, Wildlife Writer