BOS Nyaru Menteng: 5 More Orangutans Journey Back to the Wild
Date Posted: June 5, 2025
Text by: BOS Foundation Communication Team in Samboja Lestari, East Kalimantan
Meet the Orangutans
The Ministry of Forestry of the Republic of Indonesia, the Central Kalimantan Natural Resources Conservation Agency (BKSDA), and the Borneo Orangutan Survival (BOS) Foundation have conducted the 45th orangutan release from the Nyaru Menteng Rehabilitation Centre to Bukit Baka Bukit Raya National Park (TNBBBR). Here are the orangutans who were released:
Jumbo
Jumbo is a male orangutan rescued from Hanau Village, Seruyan Regency, Central Kalimantan. He arrived at the Nyaru Menteng Rehabilitation Center on February 16, 2013, when he was just six months old, weighing 4.2 kilograms.
After completing quarantine, Jumbo attended forest school and successfully graduated. He continued his learning at the pre-release site on Kaja Island on April 7, 2021. Jumbo is known as a sociable orangutan who tends to ignore human presence.
After 11 years of rehabilitation, Jumbo — now 12 years old — has mastered all the necessary survival skills to thrive in his new home in TNBBBR.
Radmala
Radmala is a female orangutan rescued in Pujon Village, Kapuas Regency, Central Kalimantan. She arrived at the Nyaru Menteng Rehabilitation Center on December 23, 2016, at the age of two, weighing 4.9 kilograms, without her mother.
Since her rescue, Radmala has shown strong wild instincts, often displaying signs of discomfort in the presence of humans. She underwent the final stage of her rehabilitation at the pre-release site on Bangamat Island on September 10, 2021. Throughout her rehabilitation journey, Radmala became known as a sociable orangutan who excels at foraging for natural food.
Now 11 years old, Radmala has successfully completed her nine-year rehabilitation. She is now ready to explore her new home in TNBBBR as a truly wild orangutan.
Pirang
Pirang is a male orangutan rescued in Kereng Pangi Village, Katingan Regency, Central Kalimantan. He arrived at the Nyaru Menteng Rehabilitation Center on December 11, 2008, at the age of one, weighing seven kilograms.
After quarantine, Pirang attended forest school and successfully passed all stages of training. On March 30, 2019, he continued the final phase of his rehabilitation on Palas Island before being transferred to Kaja Island the following year. Pirang is an adventurous orangutan with excellent foraging skills.
Now 18 years old, after undergoing 16 years of rehabilitation, Pirang is ready to embark on a new adventure with his friends in the TNBBBR wilderness.
Rongda
Rongda is a female orangutan who was repatriated from Thailand along with 47 other orangutans. She arrived at the Nyaru Menteng Rehabilitation Center on November 22, 2006, at the age of five, weighing 23 kilograms.
After a long rehabilitation journey, Rongda was given the opportunity to live at the pre-release site on Bangamat Island on January 10, 2020. She adapted well to her new environment, gradually reducing her dependence on humans. She is also highly explorative and knows how to defend herself when necessary.
Now 25 years old, after 19 years of rehabilitation, Rongda is about to regain her freedom as a truly wild orangutan in her new home at TNBBBR.
Hanau
Hanau is a female orangutan rescued in Seruyan Regency. She arrived at the Nyaru Menteng Rehabilitation Center on December 22, 2008, after being illegally kept as a pet. At the time of her rescue, she was one year old and weighed two kilograms.
Hanau successfully completed her quarantine period and joined forest school. She later advanced to the pre-release stage on Kaja Island on December 5, 2019. While on the island, Hanau attempted to cross to another area several times during the dry season. She is known for her love of exploration and her excellent foraging skills.
Now 18 years old, after 16 years of rehabilitation, Hanau is ready to embark on her journey as a truly wild orangutan in TNBBBR, alongside her companions.
Back into the Trees!