There are 7 different species of spider monkeys. They have long coats that differ in colour depending on species. Their arms and legs are very slender and they have long fingers and toes and an absent thumb, these characteristics along with their prehensile tail and flexible joints, makes navigating through forests effortless for them. Their prehensile tail has numerous touch receptors, and they use it as an extra hand. Often, they are seen dangling from a branch with just their tail holding on, in doing this they resemble a spider hanging from its thread- hence their name.
Spider monkeys are found in tropical and semi-deciduous forests in Central and South America. They live in fission-fusion communities. Fission-Fusion is when the size and composition of the social group changes. For example, spider monkeys live in groups of up to 40 members, but whilst foraging for food the group will split into smaller groups (usually one male, one female and her offspring). By doing this competition for food within the group is diminished.
70% of their diet consists of fruit, they especially enjoy overripe fruit, occasionally it’s so ripe it has fermented and the monkeys become inebriated. Their diet also consists of leaves, seeds, flowers and occasionally small insects. A typical spider monkey will live up to 30 years old. Spider monkeys have a birth season but this varies for each species. They give birth to a single infant, when that infant becomes too large to carry, and there are big gaps in the canopy, the mother will make a bridge with her body for the infant to climb over.
Spider monkeys have a slow reproduction rate, because of this they struggle to recover if population numbers fall. Hunting impacts this species significantly and nearly every species is threatened. The Ecuadorian brown-headed spider monkey is currently listed as one of The World’s 25 Most Endangered Primates due to heavy hunting and habitat loss. It is already extinct in several areas. The Geoffroy’s spider monkey also makes it on The World’s 25 Most Endangered Primates list due to being heavily hunted for food and the pet-trade. The Rainforest Trust are working with Cambugán Foundation to establish a protected area in Tesoro Escondido. Where the largest remaining population of the Ecuadorian brown-headed spider monkey reside. Currently there is an estimated population size of 150 in this region and it is a conservation priority site.
Written by Emily Elmer – Wildlife Conservation Today Contributor