Archives: July 2015

Breaking News: Yayang Has Given Birth to a New Baby!

July 29, 2015. Posted in Article

One morning, after the Post Release Monitoring (PRM) team finished their 2-day phenology activities in Mount Belah, they continued to patrol in the area of Kali Tengah to search for Sayang and her pregnant mother, Yayang (read full story here: Yayang is Expecting a Baby!).

On the first day of patrol, we did not detect any signal and only managed to locate a used nest in the hillside area of Kali Tengah, which we presumed was Yayang’s. The next day, we went back patroling in Kali Tengah, but this time we follow a different transect. From Kali Tengah, we walked up to Berlian Hill. Every 100 meters, we stopped to try and detect any orangutan signals around the area. When we reached the ridge on the way to Berlian Hill, we finally detected Yayang’s signal and tried to decide the direction of its source. Initially, we suspected that it came from another hill across the valley, which is very far. But we soon learned that we were wrong.

We slowly climbed up Berlian Hill to get better reception. When we arrived at the top, we discussed the possibilities and decided to head down to Mobil Mogok transect. We guessed that Yayang was somewhere near that transect. On our way, Yayang’s signal grew stronger and it came from a valley on our left. So we took a shortcut down the valley following the direction of the signal.

At one point, the signal was very strong indicating that Yayang was near. We slowed down and walked as silently as possible while looking for Yayang. It did not take us long to finally spot Yayang up in a tree with her daughter Sayang, eating the fruits of Lithocarpus sp. (a genus of trees related to the oaks).

Yayang and Sayang

Yayang has A Baby!

After only around two minutes of observation, someone in our team shouted excitedly, “Yayang already gave birth!” The team then realized that a small baby was clinging on Yayang’s belly. We do not know who the father was, but Yayang had been observed in the past mating with some of the males in Kehje Sewen, including Noel and Acul. In the life of this mostly solitary primate, the mother entirely bears the burden of childcare.

ribbet IMG-20150727-WA0001 a

That moment, we were all strucked with a sense of undescribable happiness. This is the first natural birth in the Kehje Sewen Forest; the first wild-born from one of our rehabilitated orangutans, giving a real hope to our goal of reviving wild orangutan population in Borneo, particularly in this case, in East Kalimantan.

ribbet by rusda

During observation, Yayang was very relaxed and ate a lot of forest fruits. Due to Yayang’s protective nature as a new mother, we decided to observe from a distance and therefore have not been able to identify the infant’s gender. We will do so in a few weeks, as soon as the baby is a little bit older and Yayang is more approachable.

With the company of an older sister and an experienced mother, we can safely hope that this baby will have a bright future as a wild orangutan.

ribbet bayi yayang by rusda

We all wish Yayang and her two children a prosperous life living in their true home, the Kehje Sewen Forest, East Kalimantan.

Text by: Tim PRM di Camp Lesik, Hutan Kehje Sewen

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A Reunion with Mona and Juminten

July 8, 2015. Posted in Article

Rain was pouring down on Kehje Sewen Forest since dawn delaying our patrol teams scheduled to head for Lembu Transect that day. Divided into two teams, we were tasked to search for our released orangutans in the area and to conduct monthly phenology activities.

After almost two hours, the rain finally stopped and the sun started to peer through the dark clouds. We rushed to get ready and soon departed to Lembu. Lucky for us, the currents of Lesik River behind the camp was not so strong, enabling us to cross easily. The next river, Lembu River, was also quite friendly in terms of currents and water levels. We reached Lembu Transect in a couple of hours.

ribbet hutan feno

Team 1 started to activate the radio telemetri equipment and stopped every 100 meters to detect orangutan signals along the transect. Team 2 headed straight to Lembu Phenology Camp to start collecting data of plants’ life cycle in the area.

ribbet patroli

ribbet flying camp

Suddenly, the phenology team received news from the patroling team who went up to Titin Hill. They detected signals of Mona! The two teams decided to search for Mona together. We raced to Titin Hill and hiked up a slippery and muddy track along the ridge of the hill. Signals were getting stronger, but where is Mona?

Finally, a colleague spotted Mona and radioed the rest of us. We changed direction and headed to the reported spot where we found Mona sitting in a tree, enjoying a lot of fruits. We were happy to see that she was in good health.

ribbet mona by guswan (2)

ribbet mona by jafar (3)

Mona was also very active moving from tree to tree. While watching Mona swinging around, we were surprised to see another individual sitting on a higher branch of a tree. It was Juminten! Just like Mona, Juminten was also in good condition and very active. Mona and Juminten hung out together for quite some time, sharing fruits and clearly enjoying each other’s company.

ribbet mona dan juminten by jafar (2)

ribbet mona dan juminten by jafar

After two hours of observation and documentation, we left Mona and Juminten in peace. It had started to rain again and considering the difficult terrain in Lembu area, we decided to call it a day. However, we were happy to get the opportunity to meet both Mona and Juminten, especially because we hadn’t seen them for a while. It was like a little reunion. Well done, teams!

Text by: PRM Team at Camp Lesik, Kehje Sewen Forest

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A Wild Day with Kehje Sewen’s Wildlife

July 1, 2015. Posted in Article

The Post Release Monitoring (PRM) team in Kehje Sewen Forest bears the main task of observing and recording the reintroduced orangutan behavior for a minimum of one year after release. The team has to conduct nest-to-nest observations and routine patrols to document how and whether the released orangutans have adapted to the new environment. Nest-to-nest observation means waking up and leaving for work before the sun rises, locating a particular orangutan nest and waiting for the orangutan to wake up, and taking notes every two minutes recording the orangutan’s activities. They do this until the orangutan builds a new nest and sleeps in the late afternoon.

Patrols are also regularly conducted on predetermined transects where the team must check the signals of each orangutan every 100 meters in the attempt to pinpoint their whereabouts. When signals are detected, they follow the signals and try to locate the orangutan. Upon getting a visual, the orangutan is observed and detailed behavior data are recorded for two hours before the team returns to the assigned transect and try to find other individuals.

While conducting these observations and patrols, the PRM team often bumps into several other wild animals living in Kehje Sewen Forest. One morning, Deny, Awal, Bowo, and Gunawan teamed up for patrol searching for an orangutan named Agus on Bukit Berlian transect.

That morning while searching for Agus, the team found a Bornean red muntjac or commonly known to the rest of us as a deer. It is the most numerous muntjac deer species and is considered to be exclusively restricted to peninsular Thailand, peninsular Malaysia, Sumatra, Java, Bali, and of course, Borneo. They also stumbled upon a forest soft-shelled turtle, locally known as labi-labi, and a cute cicada (Magicicada septendecim).



Magicicada septendecim

Around 1 PM that day, on the way to a spring, the team finally found Agus eating forest cherries (Syzygium sp.) and was able to observe him. He looked very healthy and repeatedly kiss-squeaked at the team showing his discomfort in their presence.

As a ‘bonus’ though, a macaque made an appearance. This particular monkey species is the most widespread nonhuman primate, living in many different habitats across the globe. This one, obviously, has made Kehje Sewen Forest its home. But after two hours of obeserving Agus and enjoying other forest residents that make up the rich biodiversity of Kehje Sewen Forest, the rain began to fall heavily, forcing the team to end the day and return to Camp Lesik.


Nevertheless, the team went back to Camp Lesik pleased with the day’s results. Not only that they met Agus, they also brought back a camera-full of beautiful pictures of other wildlife, indicating the wealth of Kehje Sewen Forest and the importance of protecting it for many generations to come.

Text by: Cantika Adinda, Communication and Fundraising Support

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