Species Of Interest - Orangutans

Within Sundaland there are two species of Orangutans, Sumatran and Borneo, in which both are listed as critically endangered. Both species nest high in the trees within their area of the Sundaland and have many challenges to overcome for survival.

Range of both Species

Sumatran Orangutan is an arboreal species, meaning they travel and live within the trees, rarely walking on the ground even when looking for food. Sumatran Orangutans are more social then the Borneo orangutans. The Sumatran orangutan has lost more of its habitat but has a better conserved Forrests that they do live in as they are very picky on where they choose to reside. The populations had previously been spread across all of the island of Sumatra but is now only in the Northern area of the island due to habitat loss or illegal poaching and capturing for pets.

A Sumatran Orangutan and her baby interacting with another Monkey

Borneo Orangutans are also an arboreal species, they aren't as social and male and female adults only interact during mating seasons. One issue contributing to their endangerment is the long maturation period as the females will not mate with males if they have not yet developed their cheek pads which occurs around age 20, and the babies are nursed until they are 7-8 and stay with their mothers into their teens, restricting the mother to only bearing a child once every 8 years.

Adult Male Borneo Orangutan (with cheek pads present)

Both species eat primarily fruits, leaves, bark and insects, this contributes to their ecological niche, which is the spread of seeds throughout the forrest. Trees with large seeds are especially dependent on this spreading to result in maximum reproduction. However the main predators for Sumatran Orangutans are Leopards and (of the few that are left,) Sumatran tigers. The main Predators for Borneo Orangutans are Leopards as mostly all other large predators have already been driven to extinction.