A lesser-known but fascinating species of monkey that lives exclusively on the island of Sulawesi in Indonesia. As one of several macaque species that are endemic to Sulawesi, Heck’s macaque is part of a remarkable radiation of monkeys that evolved in isolation, each species adapting to different parts of the island’s rugged, forested terrain. These macaques are notable for their stocky build, short tails, and expressive faces, which reveal a range of social behaviors and emotions.

Their fur is generally dark brown or black, with a lighter underside and a bare, pinkish face that becomes more expressive with age. They have a relatively short tail compared to other monkeys, which is common among Sulawesi macaques and gives them a somewhat ape-like appearance when moving on the ground.

These macaques live in tropical rainforests, particularly in the northern part of Sulawesi, where they are arboreal and terrestrial, meaning they move both in trees and on the forest floor. They are diurnal, active during the day, and highly social, living in multi-male, multi-female troops that can number up to 30 individuals. Social bonds are maintained through grooming, vocal communication, and play, especially among juveniles.

Heck’s macaques are omnivorous, with a diet consisting of fruits, leaves, seeds, insects, and occasionally small animals or bird eggs. They play an important ecological role as seed dispersers, helping to regenerate the forest by spreading the seeds of the fruit they consume. Their intelligence and resourcefulness are evident in the way they forage, use vocal signals, and solve social challenges within their group.

Distribution

Country

Population est.

Status

Year

Comments

Indonesia

100,000

Official estimate

VU

2015

Sulawesi