Release & Monitoring

The Orangutans that have successfully completed the rehabilitation process and qualify to be released in the wild will be taken to the release area. Their ability to be released depends partly on the medical and behavioural data collected through the rehabilitation process. Orangutans have to meet various criteria that indicate their readiness to survive in the wild. In addition to the medical and behavioural data analysis the decision making is also done in close consultation with the caretakers who observe them daily.

Release site survey

The release area has been evaluated on carrying capacity and suitability for use as a habitat for orangutans. A release area must have a good existing ecology as well as the safety, legal protection status, and support from stakeholders.

Every orangutan that will be released will be followed to monitor their condition and behaviour in the release area for 3 months after, in order to ensure and evaluate the release has been successful.

Thereafter the monitor team will continue tracking through the forest to collect data from the orangutans in the release forest. The first three groups of orangutans have telemetric microchips, which allows us to track and find them within a certain distance. The collected information provides information about the development of individuals and insight in the development of the population size. By using this method we can accurately measure their ‘home range’. We use this information as a basis for decision making and the improvement of further release processes, such as determining how many orangutans could still be released in that specific area.

Of the 14 orangutans that are currently living in Tembak forest school, there are now 5 ready for release. A release will be done with typically 3 orangutans at once with the aim to release 9 orangutans each year.

Betung Kerihun National Park
The potential release forest is the Betung Kerihun National Park, 7 hours from Sintang.  which is 816.693 Hectares.  Betung Kerihun National park, which has been a national park since 1995, contains 816.693,40 Ha of pristine rainforest. This is 5,5 % of the total surface of West Kalimantan. The Betung Kerihun National park is divided in 4 areas. There is still a population of wild orangutans living in one of these areas; called Embaloh area. The last orangutan population survey that was conducted in 2014 by Forina , WWF and Betung Kerihun National Park counted an estimated 773 wild orangutans who are living in this area.

Embaloh and Mendalam Area
Although the Embaloh area is the only area in the national park that still contains a wild orangutan population, a wider area would be suitable for orangutans to live. One of these areas is called Mendalam area  (94.523 Ha), which is the location of the planned release site.
The habitat in Mendalam area could accomodate at least 940 orangutans (assuming 1 individual needs about 100 Hectares of rainforest).

Community awareness
We are currently in the process of finalising the agreement  between SOC and Betung Kerihun National park. An effective infrastructure for security patrolling is already in place, as well as the security patrol team which is one of the responsibilities of the National Park. Contributing to ensure the safety of the forest SOC and the National Park has established a community awareness program to
create alternative sources of income without damaging forests. Besides our initiative organisations such as Forina, Diantama, GiZ and TFCA are also working on community development in this area, aiming to prevent people from diminishing forest resources, especially for trades such as timber.

Release area

Fulfilling this program increases the conservation value of the national park, due to the increased orangutan population that function as seed spreaders which improves the quality and biodiversity of the forest. This benefits the local people, since a healthy forest provides them with amongst others sufficient clean drinking water, rain, and electricity from locally built mini hydro plants. The villages closest to the border of the National park are very supportive of this program.

To ensure a successful execution of the release program, we need to establish a basecamp where from the releases are done and monitoring teams work.
The following table shows a timeline for this program and an overview of the estimated costs involved, and indicates which parts are already funded and which parts still require funding.


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