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Postcards From Borneo: My Rainforest Family

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The adult male orangutan named Codet performing a kiss-squeak call. Codet was Walimah’s preferred mate.

I never really stopped to think whether I could have children and also be a field biologist running a long-term project. When I first traveled to Borneo with Tim in 1992 I had no idea that this would be the start of a lifetime committed to studying and protecting the orangutans of Gunung Palung. But, I always knew I wanted a family, and after Tim and I married, I knew we would find a way to bring our kids here as well. Of course this wouldn’t be possible if we didn’t have complementary careers—with both the flexibility and need to travel to faraway places. Far more commonly, promising research careers get cut short because fieldwork is often incompatible with the constraints posed by spouse and children—especially for women.

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Orangutan researcher Cheryl Knott takes 11-month-old son Russell out to see a wild orangutan on his first trip to Borneo in 2001.

When our son Russell was 11 months old we brought him to Gunung Palung for the first time. I wanted him to see a wild orangutan, and even though he was too young to appreciate what he was observing high up in the canopy, I took him to see our most habituated orangutan, Marissa, and her then two-year old female infant we now call Walimah. Safely riding in a baby backpack, he obligingly touched the rough bark of the trees and gazed up at the orange apes calmly eating. Thirteen years later, I’m watching Russell wielding one of his dad’s big lenses as he’s photographing Walimah, now a young adult.

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An orangutan’s-eye view from the canopy of a fruiting dipterocarp tree with its red-winged fruits in Gunung Palung.

Walimah is up in a huge dipterocarp tree—over 160 feet high—and eating the calorie-rich seeds. We can’t get a clear view of her, and while my assistants continue to watch from above and collect data, I descend the steep slope to get to the base of the tree. There I pick up the red-winged fruits and set my watch to count how many she drops per minute so I can estimate her caloric intake. These dipterocarps only fruit once every four years or so in an event called a ‘mast’ fruiting. This family of rainforest giants dominates these forests and when they fruit many other genera of trees follow suit.

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On our very last day in the rain forest of Gunung Palung before we hiked out, we witnessed play behavior between adult female orangutans which is unusual because they are mostly solitary. That’s an orangutan ”smile” on the young female in the back, and our well-known orangutan Walimah in the front.

Since my first trip here I’ve been studying how these fluctuations in fruit dictate orangutan behavior and physiology and how they are adapted to these booms and busts in energy. I reported on this back in my first National Geographic article in August 1998. Using non-invasive techniques we can measure hormones and other markers in urine and, as the methods have advanced, we continue to discover just how ‘on the edge’ orangutan survival can be. Each year brings new surprises as the population fluctuates and individuals grow up. We’ve watched Walimah develop from a feisty infant into a young adult, intently focused on finding a mate. All year she has been actively soliciting the large flanged male, Codet, who most of the time has shown little interest in her. Unlike humans, other great ape males are not very enamored with young females. They prefer the older, more experienced mothers. So, Walimah has been working hard at gaining the males’ attention over the past year. She finally was successful and now we’re wondering if she could be pregnant.

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Cheryl Knott in the field with assistant project manager Rusda Yakin. Along with other team members, Rusda keeps the project running when Cheryl is back at Boston University during the school year.

As I stuff bags of dipterocarp fruits into my pack for later nutritional analysis I hear my family and assistants start to scramble down the hill—Walimah is on the move again—and I quickly race down after them. We are traversing one of the last patches of primary lowland dipterocarp forest in Borneo. The huge trees, hundreds of years old, provide a protective haven for the orangutans and other indigenous wildlife found here. These solid, proud giants seem invulnerable to the puny humans on the canopy floor and yet I know the intense effort that has gone into protecting them from the mighty chainsaw. Years ago, as illegal loggers started to move into the National Park, I started the Gunung Palung Orangutan Conservation Program along with my then research manager Elizabeth Yaap, to try and preserve this rainforest refuge. Working with the National Park authorities and other NGO’s we’ve so far succeeded in largely preserving one of the unique jewels of Indonesian rainforest—a park that encompasses over seven habitat types and a huge diversity of plants and animals. But, threatened by palm oil expansion, illegal logging and hunting, the protection of Gunung Palung is an ongoing challenge. Watching my kids thrive in this ultimate summer camp, and seeing the growing commitment of the Indonesian young people who we’ve helped to introduce to their country’s spectacular biodiversity, is a powerful motivator to keep up our efforts to protect this forest.

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Orangutans are so closely related to humans, that we can use over-the-counter human pregnancy tests on them. Here is Walimah’s positive test from our very last day in the forest.

As our time in Gunung Palung winds to a close this summer, I leave the research and conservation project in the capable hands of Indonesian and Western staff who continue every day to collect the long-term data needed to understand orangutans as well as to carry-out our initiatives in the villages and towns surrounding the park that are helping to preserve it. The last few days prove to be some of the most eventful of all. Walimah leads us to another female and young male and my team observes an afternoon of play and food sharing rarely witnessed in adult orangutans. On our last day in the forest, volunteer research assistant Becki Ingram collects some urine from Walimah and back at the research camp, pipettes a few drops into a pregnancy test kit. And we see…two pink lines. Walimah is pregnant!

Cheryl Knott is the executive director of the Gunung Palung Orangutan Project in Gunung Palung National Park and an Associate Professor at Boston University. Read more about her project at

This post concludes our “Postcards From Borneo” series. Over the past weeks Proof has been following the adventures of Tim, Cheryl, and their children, 10-year-old Jessica and 14-year-old Russell, in the rain forests of Borneo. Tim’s story on orangutan behavior will be featured in an upcoming issue of National Geographic. Cheryl is a 2004 Emerging Explorer and has received grants from the National Geographic Society for her work with orangutans.

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