Order Primates - Prosimians, monkeys, apes, and humans.
Family Atelidae - New World Monkeys
Scientific Name: Ateles geoffroyi
Description: These monkeys have a slender body with very long arms, legs, hands, and feet, and a prehensile tail. Length of the head and body is 15-25” and the tail is 20-35”. Weight is up to 16 ½ pounds for captive adults, but is closer to 13 pounds for wild animals. Coloration varies by subspecies from a pale tan or yellow to almost black with the underbelly usually lighter than the rest of the coat. Hands and feet are often black and most subspecies have light colored rings surrounding their eyes. The thumb is poorly developed or absent (the genus name, Ateles, means imperfect and refers to the absence of a thumb). Fingers are long and slender to form hooks. The underside of the spider monkey’s tail has a bare ridged area that is used for tactile purposes (much like an additional finger). The head is small with a prominent muzzle. Females have a long, dangling clitoris, while the male’s penis is inconspicuous.
Home Range: East and west coasts of Mexico through Panama
Habitat Type: The canopy of rain and montane forests.
Reproduction: There is no specific breeding season. The female’s cycle lasts for 24-27 days. Estrus lasts 2 days. Females give birth about every 34 months. Gestation lasts 200-232 days after which one (rarely two) infant is born. Young nurse anywhere from 10 weeks to two years. Males reach sexual maturity by five years, females by four years.
Diet in the Wild: Mainly fruit with supplements of nuts, seeds, flowers, leaves, insects, spiders and eggs.
Diet in the Zoo: Leaf eater diet, monkey chow, kale, carrots, apples, bananas and other produce when available. Also, raisins, peanuts, and peanut butter for enrichment.
General Information: Spider monkeys are entirely diurnal and they are most active in the early morning. During periods of abundant fruit, they move throughout their range stopping to feed at frequent intervals. In habits and body style, these monkeys are similar to siamangs (though siamangs are apes, not monkeys): both primates are tree-dwellers with very strong, long limbs. When they come to the ground, both may walk with their arms over their heads; however, while the spider monkey has a prehensile tail, the old-world gibbons do not. When approached by intruders in the wild, spider monkeys break off heavy limbs and attempt to drop them on the intruders. They also emit a “barking” noise when threatened. If a member of the troop becomes separated, they emit a “whinnying” sound to locate others. Troop size, as well as territory size, varies with the amount of available food. During times of abundant food, groups may fuse to form a group of up to 100 members. This large group often splits into smaller groups of 2-30 individuals when conditions are not optimum. Though females may migrate from one group to another, males tend to stay with the group they were born with. Males defend territory cooperatively.
We have two subspecies of Ateles geoffroyi at the zoo: griscescens(hooded) and geoffroyi (black-handed).
Conservation Status: Though destruction of their forest habitat is the primary cause of their decline, they have also been heavily poached for their meat, as well as for the pet trade. All primates are protected by CITES appendix II or I. The 2 subspecies we have, one is Critically Endangered and the other Vulnerable on the IUCN Red List.
Predators: Poachers, raptors, jaguars, and ocelots.
The Collins Guide to the Rare Mammals of the World. John A. Burton et al. 1987. Stephen Greene Press. New York, New York. pp.70-71.
Grzimek’s Animal Life Encyclopedias, 2nd edtion. Volume 14, Mammals III, edited by Michael Hutchins, Devra G. Kleiman, Valerius Geist, and Melissa C. McDade, 2003. Gale Group, Farmington Hills, MI. pp. 155-163.
The IUCN Mammal Red Data Book, Part 1. Jane Thornback, Ed. 1981. Unwin Brothers Limited. Surray, England. pp. 193-195.
IUCN Red List of Threatened Species. Version 2009.2. Cuarón, A.D., Morales, A., Shedden, A., Rodriguez-Luna, E. & de Grammont, P.C. 2008. Ateles geoffroyi. In: IUCN 2009. Downloaded on 01 December 2009.
Walkers Primates of the World. Ronald M. Nowak. 1999. Johns Hopkins University Press. Baltimore, Maryland. pp. 100-101.
Wild, Wild World of Animals: Monkeys & Apes. Eleanor Graves, Ed. 1976. Time Life Television Press. pp. 106-109.