A fresh start

For five years, two young Sumatran orangutans were kept as pets in a private home in Thailand. Now they are in Indonesia, at the FZS Jungle School, where soon they will begin learning the skills, they will need to someday survive independently in the forests of Bukit Tiga Puluh.

04/06/2021, Endah Wahyu

Afternoons are reserved for nest building practice for Natalee and Ung Aing, two Sumatran orangutans. They are excited for this task, grabbing the leaves and twigs their caretakers bring to their enclosure the minute the items arrive, and then enthusiastically building their nests inside their enclosure. They are making good progress. The quality of their nests improves a little more every day.

Natalee and Ung Aing are about six years old and victims of the illegal wildlife trade. When they were young, they were smuggled into Thailand where they became pets. After being confiscated from their previous owners by Thai authorities (Natural Resources and Environmental Crimes Division), they were brought back to Indonesia on the 18th of December 2020. Since then, they have been in quarantine in Jambi, Indonesia with the plan to transfer them to the Jungle School on the 5th of April 2021.

Health checks

The first stage of their quarantine was not as much fun as nest-building because, for their safety and the health of other orangutans in the country, Natalee and Ung Aing needed to undergo a few medical procedures. FZS veterinarians, Dr. Andhani Widya and Riris Prawesti examined them thoroughly for signs of tuberculosis, salmonella, malaria, and Covid-19. Fortunately, the orangutans were in good shape and all results from these tests were negative.

FZS Indonesia team transporting one of the Sumatran orangutans to its new temporary home where it will undertake a three-month quarantine. © FZS Sumatra staff
FZS veterinarian showing a sample taken from one of the orangutans. The orangutans were tested for signs of tuberculosis, salmonella, malaria, and Covid-19. © FZS Sumatra staff
Natalee getting used to her new surroundings. Soon she and Ung Aing will be going to the Jungle School to learn the skills needed to one day survive in the wild. © FZS Sumatra staff

The next step

Now the next stage of their lives can begin, this will include schooling to prepare them for independent life in the wild. They have a lot to catch up on, considering they are not babies who learn quickly and don’t have their mothers, their original teachers, with whom they normally would live for about eight years.

While still in quarantine, the orangutans are introduced to their new surrogate ‘mothers’, who are FZS trained staff, with whom they will need to develop a trust bond if they are to succeed in learning new skills. This bonding is made easier with the presence of food, which the trainers bring to the orangutans five times a day.

But the trainers want the orangutans to also enrich their minds so that they don’t become bored during their quarantine, so, the trainers give Ung Aing and Natalee puzzles to solve. Puzzles such as fruits hidden inside wrapped banana leaf parcels and unopened coconuts that they need to open are some examples. The orangutans can then examine and play with those things, while using their brains to figure out how to get to the delicious food hidden inside.

Going to school

After their three-month quarantine, the two orangutans will be transported to FZS’s Danau Alo station where they will advance their studies at the Jungle School. Here they will learn how to search for food, how to climb trees and how to build sleeping nests that won’t fall apart.

Since Ung Aing and Natalee were only a year or two old when they came into human care, it may take them a little longer to catch up and be ready for life in the jungle, explains Program Manager Dr. Peter Pratje. The trainers will try to teach them everything they need to know and monitor their progress.

A young Jungle School orangutan student (Kedaung) being released by trainer Siti Fatimatazzahra for tree-climbing lessons. Before being released into the wild, he will need to learn several skills so that he can survive in the forests of Bukit Tiga Puluh. © Daniel Rosengren

Upon graduation

Upon completion of the Jungle School, these two orangutans will join the Bukit Tiga Puluh’s orangutan population that Dr. Pratje and his team have been adding to for over 20 years. This group consists of 175 animals with similar life stories to Ung Aing and Natalee. New arrivals, as well as the increasing number of babies being born to the previously released orangutans, is helping the population grow to a stable and self-sustaining number, which Dr. Pratje says needs to be a minimum of 250 reproductive animals.

“The trainers will try to teach them everything they need to know and monitor their progress”

Dr. Peter Pratje

More about our work in Indonesia

  • Jungle School for Sumatran orangutans

  • Indonesia

    Bukit Tiga Puluh

About the author

Endah Wahyu Sulistianti is FZS Indonesia’s Public Relations Officer. Before joining FZS, Endah worked as a journalist for more than 15 years in Indonesia, focusing on environment issues such as illegal logging and wildlife poaching activity. She is a ‘Fulbright Scholar’ with a master’s degree in Documentary Filmmaking. She is an active mountaineer and scuba diver since she joined Wanadri, an Indonesian Moutain and Jungle association explorer 24 years ago.


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