The Bornean orang-utan is found inhabiting tropical and sub-tropical rainforest in the lowlands of Borneo and can also be found grazing at elevations of up to 1500 m. The Bornean orang-utan makes full use of it's surroundings dwelling both on the ground and at different heights in the trees.
The Bornean orang-utan is an omnivorous animal, but the majority of it's diet is made of fruit which the Bornean orang-utan is known to travel vast distances through the forests to find. The Bornean orang-utan also eats leaves, nuts and berries, along with insects and occasionally small animals such as lizards and rodents.
Due to it's large size, the Bornean orang-utan has no real predators on it's native island of Borneo. The biggest threat to the Bornean orang-utan is habitat loss caused by deforestation which has completely wiped out the Bornean orang-utan populations in certain areas.
The different Bornean orang-utan sexes only really come together to mate, and once born, the Bornean orang-utan baby is looked after by it's mother. The Bornean orang-utan baby clings to it's mum for the first year of it's life and may remain with her until it is nearly 10 years old. Bornean orang-utans have a relatively long childhood when compared to that of the other great apes.
Today, the Bornean orang-utan is one of the world's endangered species with less than 45,000 Bornean orang-utan individuals thought to be left in the wild. The main reason for the demise in the Bornean orang-utan populations is deforestation across the island for logging and to make way for palm oil plantations.