Post Release Monitoring Research - Update

Our research scores a first

The ultimate goal of the rehabilitation process is to produce young orangutans that are suitable for release back to the wild.  Sepilok having achieved this with our help and the Appeal is eager to find out how well these orangutans cope with their new found freedom and a couple of years ago set up a Post Release Monitoring Project.  The results of this research will benefit every rehabilitation centre!

Our primatologist has sent us this report -

I first arrived in Sabah in September 2009 to begin my role as project leader for the next stage of the Tabin post-release monitoring project. It has been a real whirlwind preparing everything for the next group of releases in June 2010, and a large amount of my time has been spent readying our research camp in preparation for my team and I living there.  This is the second group of releases that have been monitored by the Appeal but no one has lived at the camp for over a year, so there was a need to replace many of our wooden buildings. I also needed to purchase a 4x4 truck for navigating the bumpy roads of the rainforest, and employ more research assistants to help with data collection.  But most importantly I have been formulating an appropriate methodology for recording the orangutans’ progress post-release which is a job and a half in itself.

One of the most important things we are trying to achieve at this stage is encouraging the orangutans to behave more like their wild friends, and be less dependent on humans. It is important that the right orangutans are chosen to be released, ones that climb well, make nests, find their own food, and don’t really like humans! We have 3 young males all about 5 years old, Unkuyong, Atama, and Eniro, (The Tabin Three, fondly referred to as TTT) who more or less fit the bill!

What makes TTT even more special is that they are the first orangutans anywhere in the world to be implanted with a radio-telemetry transponder that transmits a VHF signal so that we can locate them in the forest! Previous trials with these transponders have been carried out in laboratories but never in the wild.  The small transmitters were placed at the back of their next just under the skin and the orang-utans are not even aware that it is there. 

Previously, without this new technology, it was exceedingly difficult to conduct the post release monitoring and carry out check-ups on their health and progress.  With this new technology everything becomes possible and what we’re doing in Tabin is ground breaking!  We are the first field project in the world to be using implanted radio-telemetry to track great apes!

Tabin was chosen for orangutan releases because it is a large area of protected mixed secondary and primary rainforest with a relatively small orangutan population, yet lots of food and suitable habitat available. Throughout my time in Sabah I have received lots of help from Dr Marc Ancrenaz and his team from Sukau.  Dr Marc, who is a senior primatologist who has been working in Sabah for many years, came to our camp in April to help us with plant identification and during this time our research assistants (RAs) and I took the opportunity to ask loads of questions about their experiences with wild orangutans in Sabah.

In the future, I will be making lots of comparisons between our rehab orangutans and wild populations, as I firmly believe we must use wild behaviour as the benchmark for all rehabilitated orangutans. My team and I are collecting data on many aspects of behaviour including nesting, activity levels, ranging and social interaction. One of the less glamorous aspects of our job, however, also includes collecting orangutan faeces to analyse the presence of parasites in their diet! Oh the joys of being a researcher eh?!

The Releases

Back in late May we moved Atama, Unkuyong & Eniro from Sepilok down to Tabin to spend a few days in our holding cage to get used to the sounds and smells of their new forest home.

After this brief period of acclimatisation, the boys were ready for their big day, so on May 31st we drove them a little deeper into the forest and then walked them in to the release site. We chose a large ficus tree that had lots of tasty fruit to try to get them eating and recognising native food species straight away. We were delighted to see all three of them climb straight to the top of the tree to begin feasting! In the month since we released, each OU has been completely self-sufficient and has been recorded eating numerous different fruits and plants. All three have also been making night nests, albeit some more than others

Unkuyong has returned to camp a couple of times to visit us already, despite having been released some three kilometres away, but hopefully this will stop as he learns that each time he does he gets returned to the forest a little further away than before! All three of the orangutans have chosen some very steep terrain to range in, which makes tracking them very difficult for the RAs but the team have managed to stay with them.  Hopefully the OUs will settle down as they become more familiar with the area.

Tabin is a great place to be if you are a fan of wildlife. We have nightly visits from Jamie, the camp’s resident Malay Civet cat, and we often hear the barking of sun bears, the long calls of the locally dominant male orangutans, and the trumping of elephants. Although I must admit that I’m not too impressed with the local elephants that came very close to camp one night.  The next morning we discovered they had bashed in the side of our yellow truck which was parked close by on the road – it must have been in their way as they passed by, or maybe they just didn’t like the colour!

The project is still in its infancy so I look forward to updating you all again soon with news on the progress of The Tabin Three. So far we have all been very happy with their development so long may that continue!