Watching and learning about apes is like learning about humans

Research Blog

Written by Desi Natalia (BNF’s Online Engagement Officer)

Understanding gibbons and their behaviour, and designing the best strategies for conserving the species, requires long-term research. BNF first began studying the Bornean white-bearded gibbon (Hylobates albibarbis) in Sebangau, Central Kalimantan in 2005 and this is now the second-longest running gibbon behavioural research project in the world. Long-term research like this cannot succeed without a skilled, local research team in the field gathering the data which can tell us how gibbons live in the forest.  Heading into the forest before dawn, the researchers use the sound of the gibbons singing to find them, and then they follow them as they travel through the forest – not an easy thing to do as the gibbons swing so smoothly and quickly through the canopy while the researchers have to navigate the difficult terrain of the peat swamp forest floor.

Now Now, let’s get acquainted with the only female Indonesian researcher at BNF, Eka Cahyaningrum, who has led BNF’s gibbon research project in the Sebangau Forest for the past 2 years.


Eka Cahyaningrum when do a follow of gibbon group
in Sebangau Forest

Photo by Duncan Murrell | BNF | LLG UPT CIMTROP

Desi : Tell me, how did you start doing primate research?

Eka : At first I wasn’t interested in primate research, because there were already so many people doing this research. But finally, I got a chance to join Macaca Nigra (Celebes Crested Macaque) research in Sulawesi. Well, that’s where I started to fall in love with primates. My partners gave me lots of encouragement to develop my skills as a researcher. I was a research assistant to PhD students and lived for 6 months in Sulawesi. After that, I worked with an orangutan reintroduction center in Sumatra for 1 year, and then I joined the BNF gibbon research project.

Desi : So, this gibbon research was the first for you?

Eka : Yes, this is the first time I’ve done research on gibbons, and I will still focus on gibbon for the future.

Desi : Wow, so you still want to continue to focus on gibbons. Why?

Eka : Yes, because gibbons are very interesting. There are already a lot of people doing research for other primates such as orangutans, and there are lots of scientific publications about it. There have also been quite a lot of scientific studies on Macaca Nigra, while the number of gibbon publications is still relatively small. So, it is very interesting to learn more about gibbons.

Desi : What made you interested and fall in love with primates?

Eka : As I said, I started to fall in love with primates when I was studying Macaca Nigra in Sulawesi. For 6 months I had to go to the field at 4 am and follow them until 7 in the evening; this was my first thing. I learned to recognise them individually and got to know their names and characters. For example, Banana was quiet and beautiful. So, the longer I observed them the more I became aware that there was something special about them, so I got to care about them more too. When I had to leave Sulawesi, I said goodbye to all individuals one by one because I felt so sad to leave them.

Also, because I met many PhD students who were very eager to talk about their projects, I became very motivated to continue researching primates. I saw that there are many foreigners focusing on primate research, but there are only a few Indonesians researchers studying primates, especially gibbons. I also noticed that there are only a few organizations focusing on gibbons. So, I decided to focus on primate research for species which still rarely get attention, like gibbons and red langurs.

Desi : Ok, that was a history about how you fell in love with primates and finally decided to focus on primate research. What about the gibbons? What did you think when you first met with them here?

Eka : Well, I’m not only here for gibbons, but also for red langurs research. There are very striking differences between Macaca Nigra, gibbons and red langurs. I could easily see Macaca Nigra under the trees as they take a nap on the ground. However, it is difficult to see gibbons and red langurs, especially gibbons which spend all their time (day and night) up in the trees. I feel fortunate meet Chilli (one of the habituated gibbons from group C), he is very entertaining and has a strong character. Other gibbons are less memorable because they do what gibbons do in general. There is a lot information to discover scientifically.

Desi : What scientific side of the gibbon do you want to understand more?

Eka : Gibbons are known as monogamous, but in some field sites there are gibbons which are not monogamous. I am curious about the background to the claim that gibbons are monogamous as some recent research is showing a change in behaviour in gibbon relationships. Many gibbons have now been found to be polygamous.

Desi : The forest ecology in Kalimantan, Sumatera, and Sulawesi are very different. Tell me about your experience in Sebangau Forest and which forest you like best.

Eka : Yes, the forests are really different. It is harder to walk in peat swamp forest than in upland forest. I used to walk more than 7 kilometres in Sulawesi, which was upland forest. It was tiring, but here in peat swamp forest, it is more tiring. I can only walk 3 kilometres maximum when following gibbons and that makes me exhausted. I need to walk carefully, sometimes slipping into the peat or falling down, getting wet, and at the same time I need to watch up in the canopy searching for the gibbons. Sometimes I want to complain, but I need to keep my mouth shut in front of other field staff. If I must choose between peat swamp and upland forest, I prefer to walk on the hills. The most challenging moment when following gibbons is when they leave their sleeping trees and then when they go to their sleeping tree again. There are no transects (forest trails) there, and it’s harder to walk off the transects. It was hard and challenging at the same time!

Chili, male juvenile gibbon from Group C
Photo by Adul | BNF | LLG UPT CIMTROP

Desi : How long so you spend following gibbons in a day?

Eka : It’s not always same, but usually we go into the forest at 5 am and come back to camp at 2 pm or sometimes at 3 pm after the gibbons are in their sleeping tree. The challenging things are we have to get up really early in the morning and get wet as soon as we walk into the forest and stay wet all the time we are following the gibbons until we get back to camp again.

Desi : How do you feel being the only Indonesian female scientist here?

Eka : There are many female scientists in Indonesia, but only a few focus on gibbons. So, I feel proud to be one of them and being the only Indonesian female scientist with BNF at the moment. But, I also feel ‘discrimination’ as a female in the field. Sometimes, the field team don’t trust me to walk further in the forest. They are really protective of me. It’s usual in Indonesia to always worry about women. I realise it’s because they care and they don’t mean to discriminate against me.  I know… but, it makes me feel like, “They underestimate me.” I really appreciate their concern and want to say thank you very much for it. They have taught me a lot about the gibbons in the field and they always help to discover many things. So, I’m really proud to be a female scientist.

Desi : And finally, please share your thoughts on why is it important to protect gibbons.

Eka : There are 20 species of gibbons in the world and all of them are endangered; some are critically endangered. There are only a few research projects studying them while their populations keep decreasing because of threats like hunting and the illegal pet trade. Now, gibbons in Sebangau Forest is facing forest fires. BNF and partners are working hard to protect this critical habitat home to gibbons and more than 6.000 orangutans. Gibbons are umbrella species like orangutans, they help regenerate forests through seed dispersal. So, when we protect gibbons, we help protect the forest and vice versa.

On this International Gibbon Day, we want to thank all scientists and field teams that provide information on gibbons from around the world. These researches give us a better understanding on how we can protect and conserve them for the future.

Fires in Sebangau Forest, a big threat to all wildlife
Photo by Eko Yudhi Aditya | BNF | LLG UPT CIMTROP