A shaggy, marmalade ape of Sumatra and Borneo, the orangutan is the only excellent ape found in Asia. Known as the man of the woods in the Malay language, this bulky tree dweller has extra-long arms to assist it get around in the trees. The orangutan is not a fast swinger but moves slowly via the branches utilizing all four limbs.

Males weigh up to 90kg and are twice the size of females. A mature breeding male is immensely strong and develops big, fleshy face flanges and a throat pouch. Although there’s only one species of orangutan you will find two subspecies – the Sumatra and Bornean – which look slightly different. The orangutan of Borneo has a rounded face while Sumatran orangutans have a longer face and are a bit thinner, paler and hairier. Sumatran males also grow beards. Male orangutans are solitary and seek the organization of females only to mate, and females also like to live alone with their offspring.

Adult males are territorial and make loud bellowing calls to let other males know where they’re. Immature males may share the range of a big male but keep well out of his way. Only when about 12 years old might a young male risk challenging a dominant breeding male, by then he has built up enough bulk and started to develop the secondary sexual characteristics – throat pouch and face flanges. Mature males that do meet display aggressively, inflating their pouches and shaking branches. Occasionally they come to blows, holding and biting each other.

Orangutans are active during the day and sleep in big nests of foliage at night. They feed mainly on fruit and consume vast amounts. A hungry orangutan may spend all day in a tree tucking into mangoes, figs, jackfruits, durians or lychees. They are expert fruit detectives and house in on the rich whiff of ripe durians and follow hornbills and pigeons to fruit trees. They also consume some leaves and young shoots, along with a few insects, tree bark and also the occasional young bird or squirrel. To obtain water they dip their hairy wrists into water-filled tree holes and suck the soggy fur.