Orangutan

Species

There are three orangutan species: Bornean, Sumatran, and the more recently recognized Tapanuli. Click here to see a short video outlining more differences between Bornean and Sumatran orangutan and click here for a short video on the Tapanuli orangutans.

Bornean

• Live in Borneo (Indonesia and Malaysia)
• Shorter, darker fur with a broader face
• Have a reputation for being on the grumpy side as adults.

Sumatran

• Live in Sumatra (Indonesia)
• Fur is lighter and longer with longer facial hairs, and a longer face 
• Have a reputation for being slightly more social and arboreal

Tapanuli

• Live in South Tapanuli in North Sumatra (Indonesia)
• Resemble Sumatran orangutans with frizzier hair, smaller heads, and big moustaches.
• They are exclusively arboreal.  

Orangutan Social Structure

Home, Home on the Range

We live high in the trees, rarely venturing to the ground.  Beyond this generality, males and females have established separate social structures.  One example is the area in which we live.  Lady orangutans do not claim individual territories but instead have overlapping ranges.  Males maintain individual territories that may overlap with several females.  

Because we live in such close confines, we often encounter other orangutans during our daily travels.  Our attitude towards others of our gender varies. Females, like me, may or may not acknowledge the other orangutan despite always being aware of their presence.  Instead, we give each other space and don’t squabble over food.  Large adult males, on the other hand, have absolutely no tolerance for other males.  When they encounter each other, the only possible outcomes are that one will flee, or the pair will fight.  Males may coexist after establishing a dominance hierarchy, with the males that are lower on the totem pole removing themselves when they hear the dominant male approaching.

Friends and Enemies

Adult females live with their offspring and sometimes travel and rest with a friend for several days at a time.  We don’t embrace or groom our friends so it may appear to you that we are oblivious to each other. But I’m relaxed in the company of my friends, and we can eat in the same tree without coming to blows.  We may go for months, or even years, without seeing each other but remember our friends nonetheless. I will never turn on my friends.  However, there are other females with whom I’m less enamored. I’m prone to assaulting or chasing them away when the mood strikes me.   

Cheekpadders

Click here to see a short video of a cheekpadder.

Adult males that have not developed cheekpads are roughly the same size as us ladies – 100 pounds (45 kilograms).  They may travel together to seek female companionship, sometimes using force to persuade us.    If one of these male winds up in a location without a resident cheekpadder, they may grow to fulfill that role.  Others retain their smaller statures throughout their lifetime.  Unflanged males may also father our children.

Growing Up Orangutan

In the Beginning

My mom and I were super close when I was a wee tyke.  She was extremely protective of me then – no one else could touch me and she even shielded me from being viewed by others.  Click here to see what she was hiding – so much cuteness!

For my first six months, I was physically glued to Mom.  I clung to her as we traversed the forest.  When she stopped to eat, I would crawl around on her.  But even in sleep, we were always touching.  After that, I began to take a few tentative steps away from her at mealtimes. Even when I was a year old, though, I’d never venture more than a few feet away from Mom.

Despite occasional visits from other orangutans, Mom and I were mostly on our own.  During my second year, I still relied on Mom for transportation.  But I began to forage for myself – sometimes taking food from her mouth.  I was generally a very docile baby, but one time Mom tried to prevent me from sharing her jackfruit and I just screamed and screamed until she was ok with it.  I was such a little imp!  Sometimes Mom and I would play together, but mostly I entertained myself by manipulating branches and twigs.  I even imitated the way Mom built our night nest by snapping some twigs to make a mini nest.  

For the next few years, I continued to rely on Mom’s taxi service.  But more and more, I explored on my own, albeit always within her visual field. As I turned 5 years old, I began to travel on my own accord, following just behind Mom.  I learned the orangutan special technique to traverse the treetops — I rock the tree or lianas (swinging vines) to bridge the gap.  Click here to see a demo. 

Adolescence

As I approached my eighth birthday, Mom’s milk slowly trickled to a stop.  By then, I had learned how to find food, build my own nest, and move about the forest.  Nonetheless, I remained with Mom so I could become a master forager like her.  After all, there are over one thousand food items available in our forest and I needed to know which I could eat, and when and where each was available.  Like, how often and when do particular trees fruit, which berries burst during what season, and where were the termites hatching.  I even had to learn how to eat some tricky food items like spiky fruits so I didn’t hurt myself.  (The trick is to hold it with a leaf!) 

Shortly after being weaned, I gained a new sibling: Aminah.  She’d often grab my arm or my foot to get my attention and then we’d play.  I was always so gentle with her, and it helped me learn how to handle wee ones. 

With Aminah claiming most of Mom’s attention, I sometimes drifted away from them to explore the forest with Binti.  We’d sit side-by-side, sometimes holding hands.  Dewi and Zarina joined us on occasion, and we’d travel together for several weeks at a time.  We generally avoided adults when we were together, but sometimes a few boys our age joined us — although they spent more time wrestling and play fighting with each other than anything else.

Time passed in this delightful manner.  As I grew older, I often had a harem of boys my age surrounding me.  But I only had eyes for our local cheekpadder, Malik.  I shamelessly flirted with him, but he treated me more like a chaperone than a suitor. 

Adulting, Orangutan Style

My relationship with Malik changed when I was 14.  He had disappeared for a while but returned to chase off all the other males by staring menacingly and inflating his throat pouch while long-calling and shaking branches. Luckily, the other males all left to avoid combat.  Malik and I enjoyed a consortship for the next several months.  As our association declined, I began to spend more time by myself.  Eight and a half months later, our son Ali was born.  I was solely responsible for his care, which included feeding and protecting him. 

Most of the time, it was just me and Ali going through our day together.  Like all baby orangutans do, Ali clung to me for his first six months before he began exploring a few feet from me.  Occasionally Binti would join us with her daughter, Bermai.  While Binti and I no longer touched or sat directly next to each other, our bond remained strong.

Occasionally other orangutans in our range would come a little too close for my liking.  Like my mother before me, I chased them all away, biting the more reluctant ones to make my point clear.  I didn’t want them near me and Ali.

While I might have had my cantankerous moments, Ali was a sweet baby.  But because he was a boy, as he got older, I had to push him to independence.  The first step, when he was 5, was forcing him to travel on his own rather than relying on me to transport him.  He threw a lot of temper tantrums to persuade me to carry him.  I sometimes relented but eventually he tagged along just behind me.  When he was 7, I began pulling away when Ali tried to nurse.  He’d squeal and race down the branch with his little limbs flailing.  We repeated this routine many times daily for several months before he accepted this change.  To further encourage his autonomy, I began to leave him behind when I foraged.  That often provoked him too and he would protest until I waited for him to catch up.

Eventually Ali began spending time with other boys his age.  I’d watch them wrestle, play fight, and hit each other before moving on with my day.  Ali was ten now and while we maintained some contact for a while, he was at the point where he could survive on his own.  We spent more and more time apart until Ali finally left the area to seek a new home for himself.

Things are different with Amani and me.  I have no need to chase my daughter away.  Instead, I let her assert her independence gradually. Even though she is now an adult, we share a range and continue to spend time together.

A Typical Day for Me as an Adult

Dawn Patrol

My typical day begins at dawn when I head to the nearest fruit tree for my first meal of the day.  This is not always as simple as it may sound.  Despite there being over 1,000 fruits and nuts available, the rainforest does not consistently produce them, with some only maturing once every couple of years.  There are times, like in January, that I enjoy many options.  But there are other periods, like in May, when I may struggle to feed myself no matter how far I travel.  On days when there is simply no fruit to be found, I eat leaves, nuts, bark, flowers, and insects, like termites.  On very rare occasions, I may eat bird eggs or a slow loris.

I spend my morning splitting time between resting and traveling / foraging.  After an hour in a tree, I move on to a new location by accessing my mental map of food sources, distances, routes, and obstacles.  I travel the most efficient route to my next feeding spot, sometimes making a short detour to monitor other trees that are in different phases of fruiting.  If I pass a tree with a depression in the fork, I will stop for a drink of water.

Afternoon Delight

By mid-morning, it’s very hot in the rainforest so I relocate to a cooler spot. Some days, I simply drape myself on a comfortable branch or liana.  Otherwise, I make a small day nest on a ridge top so I can catch a breeze.

In the mid-afternoon, I get up to find a little protein, such as tree ants.  I break off a chunk of their nest and hold it to my mouth so the ants will stream in.  They bite my lips, but I ignore them, shooing away only those that make it to my fur.

Bedtime

Click here to see how we make our nests.

Over the course of the day, I have zigzagged between 300-1,000 yards (275 – 900 meters) from where I started. By late afternoon, I’m ready to retire so I grab a few more pieces of fruit and head to a nearby broad-trunked tree to make my nest.  After I select a strong limb for support, I spend a few minutes bending and twisting smaller branches at 90-degree angles, folding them into a springy, circular platform.  Over the next 30 minutes, I embellish my nest with loose leafy branches piled on top of each other for a mattress that’s a foot thick.  I may also gather some leafy twigs to serve as pillows and a blanket and braid the leaves overhead into a roof.  The result is a bouncy, comfortable place to lay my head.  About an hour before sunset, I curl up in my new nest to sleep.

How You Can Help Us.

Because we’ve lost 97.5% of our historical range, you can support groups that work to preserve our habitat or connect us using corridors.  You can also help by making sure any product with palm oil or wood products, like furniture, are sustainably made.  There are several handy apps that can help you such as the Palm Oil Scan.  Also, because climate change is exacerbating the fires that are destroying our home, you can take action to reduce your carbon footprint.  Finally, other nonprofits work to reinforce protected areas to prevent illegal activity like removing infants for the pet trade and harming us as a result of human-orangutan conflict.

Returning the Favor.

Orangutans often favor the peace and tranquility of solitude.  Even when we share time with our closest friends, we occupy the same space without interacting.  There is no void to fill when you are at peace.  I highly recommend incorporating some “me-time” into your regular routine. Tap into your inner orangutan to reduce the stress of everyday life.  We also remain bonded to our friends, even when we haven’t seen them for years.  Consider reaching out to an old friend you haven’t talked to in a while.  You know you want to! 

For more information on orangutans, you can check out Orangutan Outreach’s FAQs here.  If you’d like a more in-depth source, read Reflections of Eden by Birute Galdikas. If you’d like to experience orangutans in-person, some of your best bets are the San Diego Zoo & Safari Park, Zoo Atlanta, Woodland Park Zoo in Seattle, and Singapore Zoo.  If you’d like to watch orangutans remotely, try the San Diego Zoo Ape Cam.

Special thanks to Orangutan Outreach’s Debbie Clemens, MA, CIG for serving as the expert advisor on orangutans.

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