Animals

Things you need to know about orangutans

Fascinating facts about these great apes.

In recent years, these gentle red great apes have had the unfortunately honour on of becoming the public face of deforestation and the problem of palm oil.

Only found on the islands of Borneo and Sumatra, the Orangutan is a magnificent, but critically endangered, species. Well, multiple species. Three different species of Orangutan have been identified: the Bornean, the Sumatran, and the Tapanuli, which was only confirmed as a species in 2017.

The word “orangutan” comes from the Malay ‘orang’ for person and ‘hutan’ for forest. The full translation of ‘person of the forest’ is apt as we share 97% of our DNA with this great ape.

With their hand-like feet, orangutans are incredibly dexterous and agile, travelling with ease through the trees. Like all great apes, they have large brains. Combining this with their dexterous digits, orangutans exhibit behaviour we might consider ‘human’. They use tools such as sticks to fish termites, ants and bees out of holes in trees. They have also been observed making themselves a type of glove from leaves which protects their hands from thorny branches and spiky fruit. Orangutans even a rudimentary equivalent of an umbrella, as they hold large leaves over their heads to shelter from the rain!

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organutans — A mother orangutan will use her limbs to form a bridge between trees for her baby. © Nick Green | BBC NHU

While they are tenaciously resourceful, orangutan population is in decline due to the devastation of their habitats. Estimates put their population at 57,000 - 100,000 Bornean, less than 14,000 Sumatran and fewer than 800 Tapanuli orangutans. They face a multitude of threats, with the biggest causes being deforestation, illegal hunting for meat and the pet-trade.

There are so many causes for deforestation in the area, including logging, palm oil production, mining and agricultural expansion, and the scale of it is devastating. In under 40 years, Borneo has lost 10 million hectares, or 39%, of its original forest cover. However, the destruction of their habitats is not solely due to human activities. Due to climate change, forest fires are becoming more frequent and devastate the orangutan population. For example, the 1997-98 forest fires in Kalimantan, killed up to 8,000 orangutans. While there are designated protected areas for orangutans, this is proving ineffective. According to the Orangutan Foundation, 80% of orangutans live outside of protected areas. The Bornean orangutan population is predicted to decline by 86% from 1950 to 2025, due to habitat loss.

While the deck seems to be stacked against orangutans, there are main organisations fighting for them. One is the previously mentioned Orangutan Foundation. Founded in 1990, they work with both the Indonesian Ministry of Environment and Forestry and local communities to bolster conservation and research efforts, as well as disseminating a greater understanding about orangutans to those who interact with them. There is also the team at International Animal Rescue who work on the front line to save orangutan from habitat destruction and the illegal wildlife trade. Since 2009 they have rescued over 200 orangutans and are currently caring for 111.

organutan — Orangutans are the largest tree-dwelling mammals in the world.

They are the largest tree-dwelling mammal, spending 90% of their time in the forest canopy looking for food, and sleeping. Their preferred habitat is low-lying tropical peat forest, and due to their food preferences, are rarely found above 500m. They require vast stretches of forest to find enough food and mates. When travelling through the forest, they can snap and break off branches, creating gaps in the canopy. This allows light to reach the forest floor, encouraging new growth and thereby regenerating the forest naturally. This isn’t the only positive ecological role that orangutans perform. As they travel, they disperse seeds that get trapped in their fur (and presumably in their feces – orangutans also spit out seeds from certain fruits). This has earned them the nickname ‘the gardeners of the forest’.

Competition for food is tough, leading to a semi-solitary existence, which is unique among primate species. Their diet is comprised of 60% fruit with the stinky durian fruit being a favourite. They’re known to eat over 400 different foods and when fruit is scarce, they’ll resort to eating bark and leaves.

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