Geoffroy's spider monkey

Spider monkeys live in Mexico and Central America.

They live high up in the trees of warm forests.

Geoffroy's spider monkeys live in southern Mexico and every country of Central America: Belize, Guatemala, Honduras, El Salvador, Nicaragua, Costa Rica and Panama.

They live in many kinds of forest: rainforest, forest where some trees drop their leaves in the dry season, and even mangroves on the coast. They like evergreen forest best, because it has the most fruit. They spend nearly all their time high in the trees and need big areas of forest that are joined together.

Older accounts describe a range along both coasts of Mexico from Tamaulipas and Jalisco southward (Animal Diversity Web, 2002). The IUCN assessment (assessed 2020, published 2021) lists the Mexican states of Campeche, Chiapas, Oaxaca and Quintana Roo, then Belize, Guatemala, Honduras, El Salvador, Nicaragua, Costa Rica and Panama, from sea level to 2,500 meters. Some evidence suggests the southernmost subspecies may reach a small area of Colombia near the Panama border.

It uses evergreen and semideciduous tropical forest, montane forest and coastal mangroves, but is most often found in evergreen forest where fruit is plentiful. Spider monkeys tolerate some logging but need large areas of tall, continuous forest, which is why they are considered an indicator of forest health.

Spider monkeys love ripe fruit.

When there is not much fruit, they eat young leaves and flowers.

Spider monkeys are frugivores: most of what they eat is ripe fruit, which gives them the sugar they need for their long trips through the treetops.

Fruit trees ripen at different times, so spider monkeys must remember where lots of fruit trees are and travel far to find them. When fruit is scarce, they eat young leaves, flowers, seeds and buds, and once in a while a few insects. As they travel, they drop seeds all over the forest, helping new trees grow.

The diet is dominated by ripe fruit; leaves, flowers, seeds, nuts and buds are eaten less often, especially when fruit is scarce, and insects, spiders and eggs only occasionally (Animal Diversity Web; New England Primate Conservancy). Young leaves are preferred because they are easier to digest.

Because fruiting trees are scattered and seasonal, spider monkeys depend on spatial memory and travel widely. Feeding is heaviest in the early morning. Swallowing fruit and moving long distances makes them important seed dispersers for tropical forest trees.

Spider monkeys live in big groups.

The group splits into small teams to find food. Later they meet up again.

A spider monkey community can have up to about 40 members, but they are almost never all together. Instead, the group splits into small parties to look for fruit, then joins up again later. Scientists call this fission-fusion.

Females often travel alone or with their young, while males tend to stick together. Spider monkeys keep in touch with loud barks, whinnies and screams that carry through the forest, and they use faces, touch and grooming to stay friends.

Communities of up to about 40 (Animal Diversity Web reports groups of about 30, occasionally up to 100) have a fission-fusion structure: members forage in small, shifting subgroups whose size depends on age, sex and fruit supply, which reduces feeding competition. Females range alone or with offspring; males stay together and keep strong bonds (New England Primate Conservancy).

Long-distance barks, whinnies and screams locate scattered members and warn of predators such as jaguars and pumas; separated animals give whinny-like calls. Close-range whimpers, facial expressions, postures and grooming maintain relationships.

Spider monkeys are endangered.

Many forests have been cut down. People are joining forests back together so the monkeys can travel.

Geoffroy's spider monkey is Endangered. The biggest problem is that forests are cleared for farms, cattle, logging and towns, leaving small patches. Spider monkeys are also hunted and caught for the illegal pet trade. Because they have babies so slowly, their numbers are slow to recover.

National parks and reserves protect some forests. Conservation groups also plant wildlife corridors, strips of forest that join patches together, and work with farmers to protect trees.

The IUCN lists Ateles geoffroyi as Endangered, with a decreasing population (Cortes-Ortiz and colleagues, assessed 2020, published 2021). Habitat loss to agriculture, cattle ranching, logging and urban growth is the main threat; fragmentation makes food harder to find and splits communities. Hunting and the illegal wildlife trade add to losses, and the species has disappeared from most easily reached areas (Animal Diversity Web).

It is listed in CITES Appendix II, with some subspecies in Appendix I. Conservation focuses on protected areas, forest restoration, wildlife corridors and community programs such as shade-grown agriculture (New England Primate Conservancy).