Two Families Reunite

Sif and Emen’s Families

It has been more than a year since Sif and her daughter Sifa were released into Bukit Batikap Conservation Forest. They were last observed in July 2013, and despite the Team’s efforts to locate them, they had not been seen since. Unintentionally, the Monitoring Team found this pair just recently when crossing Joloi River on their way back from gathering phenology data.  In fact they found two families, the first being Emen and her son Embong who were in a tree by the Joloi River.  Delighted, the Team was preparing to take photo’s, when they saw another pair of orangutans in the same tree, Sif and Sifa. Sifa was on the highest branch and  started dropping branches while kiss-squeaking towards the Team.


Little Sifa

Emen and Embong didn’t seem to pay any special attention to the Team’s presence and sat idly watching Sifa throwing vegetation at the Team.

The next day, the Team returned to the same location. The orangutans had moved not far away. Sifa behaved like a wild orangutan should and together with Embong they played, pulling each other’s hands, throwing leaves and fruit. Embong is still more attached to his mother and nursed every now and then while playing with Sifa.

The mothers Sif and Emen, meanwhile, sat eating fruit together. Emen appeared to eat Sif’s choice of food and when the group moved on, Emen followed Sif.  It was great to see the two families healthy and spending time together.

Embong and Sifa

Embong and Sifa

Slamet, Miss Owen and the bees

Since his release day back in April 2014, Slamet, who was very enthusiastic once he stepped out of his travel cage, has been seen in the company of Miss Owen and several other female orangutans.

On his first day in Bukit Batikap, Slamet approached Miss Owen and she didn’t seem to avoid his advances.



Their togetherness went on for some time until they encountered a swarm of bees. Slamet was stung several times on the face while Miss Owen fled to the banks of Joloi River.  Let’s hope we see these two again together soon.


Text: Ike N. Naya Silana


News from Kitty and Kate

Kitty and Kate
Kitty and her daughter Kate were the 100th and 101st orangutans to be released into the Bukit Batikap Conservation Forest by the BOS Foundation in Nyaru Menteng. After their release in February 2014, they were gone for several days. The Monitoring Team tried to locate their position without luck. A few days later, their weak signal was picked up away from the monitoring transects. The Team decided to follow the signal and try to locate them.

Kitty and Kate were found at 14.56, just four minutes before the transmitters turned off automatically. All our transmitting devices are pre-programmed and this allows us to follow the orangutans for a certain number of hours a day. The weather was not good with heavy rain and strong winds which caused some trees to fall. The Team, however, remained in the location where they found Kitty and Kate to ensure their wellbeing.

Kate and her mum

Kate and her mum

Kitty and Kate sheltered under the leaves from the rain, five meters from each other. They continued eating young leaves despite the weather. When the Team moved to avoid a falling tree, Kitty was made aware of the Team’s presence. She quickly grabbed Kate and threw branches towards the Team and kiss-squeaked.

Kitty quickly moved away from the Team, climbed a tree and hid behind the big tree trunk. When the Team persisted with their data collection efforts, Kitty once again kiss-squeaked and threw branches. Seeing their wild behaviour, and also reviewing the weather situation which was becoming increasingly worse, the Team decided to leave the mother and child pair. They were healthy and really that is the most important factor to establish.

The Intelligent Mego
Orangutans are intelligent creatures who are able to innovate tools. Mego who was released on April 20 2014, was observed measuring the depth of Joloi River using a wooden stick.

Mego used a longbranch to measure the river depth by dipping it into the water.  He plunged into the water trying to cross the river but changed his mind after his stick floated off down stream.



Mego has been using this method ever since his time living on Palas Island, one of our pre-release islands close to Nyaru Menteng. This behaviour was also displayed by both Menteng and Danur who lived on Kaja Island. Fascinating behavior which again just shows us how incredibly cognitive these great apes are.


Text: Ike N. Nayasilana