We recently collaborated with the local Forestry Department (BKSDA) on the release of two orangutans (Pongo pygmaeus) in the protected forest of Mount Tarak, in Ketapang district, West Kalimantan (Indonesian Borneo.) The release operation was carried out on Tuesday 10 July.
The orangutans were a mother named Maili who is aged about 10 years old and her son Osin who is 14 months old. Maili had undergone rehabilitation at our centre in Sungai Awan, Ketapang after our team rescued her from captivity in 2015 from Batu Ampar in Kubu Raya Regency. During the rehabilitation process orangutans are placed in groups on artificial islands where they live in an environment which simulates their natural habitat. This helps to restore their natural instincts and behaviour.
The orangutans are able to hone their natural skills, spending their days climbing, foraging for food and building a nest to sleep in each night. Baby Osin was the result of a union between Maili and one of the male orangutans on the island while they were both undergoing rehabilitation.
Before they are released, candidates for reintroduction are moved to a special area where they are closely monitored and behavioural data is gathered on each individual. This is to ensure that the orangutans are physically and psychologically equipped to fend for themselves in their natural habitat.
Our monitoring team began gathering data on Maili early last year in preparation for her release. However, when she underwent a medical examination it was discovered that she was pregnant and so the release was postponed.
Once her baby had been born, the team resumed monitoring her behaviour which confirmed that Maili was exhibiting good natural behaviour and that her son was developing well. The journey to the release site from our centre on the Awan river involved travelling for four hours by road, followed by a four and a half hour trek deep into the forest. Twelve local villagers acted as porters and carried the transport cage to the designated release site.
When the team arrived, the orangutans’ cage was opened by Karmele Llano Sanchez, our Programme Director in Indonesia. Because Maili has undergone rehabilitation, she will continue to be observed and her progress monitored for a further one to two years.
The monitoring team is made up of people from the hamlets around Mount Tarak Forest. Their work involves following the orangutans from dawn until dusk each day and gathering behavioural data on them during their waking hours. As well as monitoring Maili and Osin, the team are also monitoring some orangutans that were previously released on Mount Tarak.
“Monitoring is carried out to ensure the orangutans are not only surviving but thriving back in the forest. If the condition of one of the animals gives them cause for concern, then the medical team is called in to assess and assist them,” said Argitoe Ranting, our Survey, Release and Monitoring Manager.
Sadtata Noor, Head of the West Kalimantan BKSDA, said: “We greatly appreciate the efforts of IAR Indonesia and the local community in making this valuable contribution to wildlife conservation. This work is very challenging and we applaud their commitment and loyalty. Bravo!” Dr Karmele Llano Sanchez, said: “It is so uplifting to witness Maili and Osin climbing the trees in their natural habitat. I am thrilled they can both return to their rightful home – and on my birthday too! Their release is the most precious gift of all.”