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Together, the Ministry of Environment and Forestry (KLHK), the East Kalimantan Conservation and Natural Resources Agency (BKSDA), and the Borneo Orangutan Survival (BOS) Foundation have successfully released five rehabilitated orangutans into the Kehje Sewen Forest ecosystem restoration concession. 

This release comes after a two-year break in release activities by the BOS Foundation in East Kalimantan, with the prior release in the area taking place on February 18, 2021. The newest release operation started on May 16, 2023, and ended successfully with the five orangutans proving they had finished the long rehabilitation process at the Samboja Lestari Rehabilitation Centre, East Kalimantan, and were ready to live in their true forest home.

Strict health protocols
Although the World Health Organization (WHO) lifted the emergency status of the COVID-19 pandemic on May 5, the BOS Foundation continues to strictly implement health protocols for the release of new orangutans. The well-designed release scheme went smoothly despite some unexpected hurdles. 

The team left by car for Muara Wahau from Samboja Lestari Rehabilitation Centre around 11.00 AM local time. After taking approximately 12 hours to arrive at the first stop, the team continued their journey to Pier 67 and crossed the Telen River. This pier is the team’s main gateway to the release points in the Kehje Sewen Forest.

However, reaching Pier 67 is no easy task. As they travelled the dirt roads, the team encountered a landslide that had damaged the already fragile bridge. At this point, all human passengers had to exit the cars and continue on foot. Meanwhile, the skilled drivers had to very carefully navigate what little had remained intact for the sake of the orangutans watching from their transport cages in the flatbed. The painstaking crossing was worthwhile, as all vehicles made it to the other side, where the team finally loaded the orangutans into the motorised boats that awaited them. One by one, the cages were moved to the opposite side of the Telen River, to the release point.

A long journey to two release points
After a 20-hour journey by land and river from Samboja Lestari Rehabilitation Centre to the south side of Kehje Sewen Forest, five orangutan transport cages were successfully opened at two different points. Mayer and Elaine were released at the first location, while Andreas, Leann, and Riana took their first steps into freedom at the second release point.

The team members opened Mayer’s cage first. This male orangutan aggressively displayed towards them, which is not uncommon as each orangutan copes with the long and stressful journey in their own way. Once he settled down, just like the others, all he wanted to do was eat the remains of the food provisioned by the journey before finally finding a tree where he could feed on wild fruit and leaves.

Carrying the heavy transport boxes through the mud is no walk in the park.

Elaine’s reaction to the transport cage opening was completely different. She immediately started exploring her new environment, climbing into nearby vegetation. Her first stop in the Kehje Sewen forest was the comfortable branches of a rasamala tree (Altingia excelsa).

Love at first sight
Andreas’s transport cage was opened at the next release point. The active male immediately climbed the tree in front of him and made a nest. However, his rest came to an end the moment Leann’s stepped into freedom. Andreas greeted his new neighbour and made his interest in her well-known, ending with the new pair copulating. We could not be more proud of Andreas and Leann, already making themselves at home and trying to naturally grow the number of orangutans in Kehje Sewen.

Love was in the air after Andreas spotted his female fellow release candidate Leann.

Lastly, the team opened Riana’s cage. She emerged and did not take immediate action; instead, she took in her new surroundings before moving closer to Andreas and Leann. On their first day in the forest, the trio stayed within a few metres of one another. As the sun set, Riana got to work, making a nest for herself to sleep peacefully that evening.

We sincerely hope these five rehabilitated orangutans can adjust well to their new home, the Kehje Sewen Forest. However, it should be fine as the meaning of Kehje Sewen in the location Wehea Dayak language is ‘Home of Orangutans’. With the arrival of these five orangutans, the reintroduced orangutan population of Kehje Sewen rises to 126 individuals, and the potential for new baby orangutans grows. 

Enjoy the freedom you worked so hard to achieve, Riana, Leann, Andreas, Elaine, and Mayer!

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