Peruvian spider monkey

Appearance

The Peruvian spider monkey weighs up to 9 kilograms. Its body can be 70 cm long and the tail can be 1 m long. It has four elongated fingers and virtually no thumb, which is typical for spider monkeys but unusual for other monkeys. It can move easily through the trees and it has a prehensile tail like other species in the genus "Ateles", which it uses to assist with brachiation. It has an agility that can only be compared to the gibbon of Asia. It has a life span of up to 20 years.

Naming

In addition to external appearance, the Peruvian spider monkey differs from the red-faced spider monkey by the number of chromosomes in addition to several specific chromosomal differences. The two species have been interbred in captivity, resulting in offspring with reduced fertility. There are several related species such as the Central American spider monkey or Geoffroy's spider monkey, and the brown spider monkey and the species' closest relative the white-bellied spider monkey. All of these have a prehensile tail, a thumbless hand, and other characteristics that are found in all spider monkeys.

Distribution

The species occurs in central-northern of Bolivia, north-eastern Peru, and the central-western Brazilian Amazon. The species was recently found to occur in the northern bank of Solimões River, at the Mamirauá Reserve, where it probably colonized through a river meander cutoff process.

Habitat

They live primarily in lowland forests, occupying the canopy and the sub-canopy, but they have been observed using various habitat types, including dry and hilly areas such as the piedmont and cerrado forests, and have been observed to move depending on food availability. They were also observed living in Amazonian seasonally flooded forests. They live in territorial bands of 6–12 individuals whose territory covers about 20 square kilometers. Band size is somewhat seasonal, probably because females separate themselves from the band for a few months to give birth, primarily in the fall. It has to contest with other spider monkeys, woolly monkeys, and howler monkeys for food and territory.

Reproduction

The spider monkey has a reproductive period that can span throughout the year, though most offspring are born at the start of the Autumn season. It has a gestation period of about 140 days. The pregnant female leaves the group to have her baby and returns 2–4 months later. The newborn spider monkey is independent at about 10 months.

Food

The Peruvian spider monkey feeds on leaves, berries, small animals such as birds and frogs, flowers, termites, honey, grubs, and fruits. It is primarily frugivorous with a tendency to exhibit folivory in times of fruit scarcity. It will also eat insects, baby birds, bird eggs, and frogs. In the Amazon, groups of Peruvian spider monkeys show strong seasonal variations in habitat based on the availability of fleshy fruits. The foraging habits of this species causes the monkeys to be a vital component of seed dispersal patterns for many tree species in Amazonia.