Sumatran Orangutan
Orangutan mother and her baby
Semi-wild Orangutans drinking milk
Wild Orangutan in the rainforest
Orangutan in a tree near Bukit Lawang
Orangutan baby in the Gunung Leuser National Park
Orangutan male in the Jungle

Sumatran Orangutans

Orangutan, the world's largest arboreal mammal, means "people of the forest" (Orang - people, Hutan - forest) in Indonesia. Once they were widespread throughout Southeast Asia, but now orangutans are limited in the wild to only two places in the world, Sumatra and Borneo. The International Union for Conservation of Nature lists Sumatran orangutans as critically endangered. Current estimates suggest that they could be the first great ape species to become extinct in the wild!

The Sumatran orangutans (Pongo abelii) are rarer and smaller than the Bornean relatives, have lighter hair and a longer beard. Today there are approximately only around 6.600 left in the wild, most of them in the provinces of Aceh and North Sumatra. The expansion of oil palm plantations into fragile Eco-systems is the most acute threat to their survival. But also illegal logging and pet trade add to their declining population.

It's really a memorable experience to watch the orangutans in the tropical rainforest of Gunung Leuser National Park, but this animals should be really protected with care. The great apes share over 96.5% of its genetic DNA with us, they are highly intelligent, thinking and feeling like human beings and they are like us in many other ways. But just an influenza - caused by a human visitor in the rainforest - can potentially kill an orangutan! It is a necessity that no direct contact takes place there! For their protection it is forbidden to enter the rainforest without a registered and experienced guide.

However, an excursion to the old feeding area near Bukit Lawang is still an unforgettable experience for everybody! Visitors are able to see semi-wild orangutans there in a quite close distance. Since the Bohorok Centre for ex-captive Sumatran orangutans was established in 1973, more than 200 orangutans have been released into the Gunung Leuser National Park. Even though it doesn't operate  as a rehabilitation center any longer, the area is open for tourists to take memorable impressions home. Until December 2015 the orangutans normally got fed twice a day with bananas and milk to adapt them to fodder in the wild. The continuous feeding helped the rangers to observe the great apes in order to make sure that they are managing their live well in the wild. The official feeding through national park rangers has recently been stopped but this area is still highly popular with a lot of orangutans.

Orangutans spend most of their lives in the tops of the trees and climb from branch to branch. They can make several kilometers per day, looking for food and making a new nest each night in a tree for sleeping, only coming together for minimal social interaction. Their diet generally consists of vegetarian items and insects. This great apes prefer leaves and fruits including figs and jack fruits, but they also often eat bird eggs, small vertebrates, termites or ants.

The Sumatran orangutans grow to about 1.4 meters tall and males weigh up to 80 kilograms. Females are smaller, 90 centimeters on average and they weigh up to 40 kilograms. Their life span is long, often around 45 years in the wild. And they have the longest inter-birth interval of any land-living animal, producing a single infant only around once every 8 years. The infants stay then with their mother until they are 7-10 years old. So a female will usually have no more than 3 offspring in her life.

Orangutans are quite intelligent and their way of life isn't compatible with a shrinking forest. The Gunung Leuser National Park is one of the most biodiverse rainforests of the world and urgently needs to get protected. By preserving the habitat of orangutans you help protect other rare wildlife there such as the Sumatran elephant, rhinoceros and tiger. And with a sensitive balanced Eco tourism, offered by Sumatra EcoTravel, you also support a livelihood for many Indonesian people living around there! Because both, humans and wildlife, depend on the conservation of the environment.

The Sumatran Orangutan Society (SOS) and the Orangutan Information Centre (OIC) in Bukit Lawang produced an informative guidebook, which covers a broad introduction about the Gunung Leuser National Park, the fauna and flora, and current threats to the fragile ecosystem. It takes an in-depth look at the ecology and conservation status of the Sumatran orangutans, as well as the benefits of Eco tourism, and the problems that can arise from its mismanagement.

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