Biruté Galdikas Reveals: Tracking Orangutans Through Neck-Deep Marshes

The British primatologist Jane Goodall, who passed away on October 1st at the age of 91, was a pioneering and legendary figure in her field. Her relentless research on chimpanzees, beginning with her arrival in Tanzania in 1960, transformed our understanding of our closest relatives.

However, two other women, less known in France but equally remarkable, also made significant contributions. Dian Fossey, who studied gorillas, and Biruté Galdikas, who was fascinated by orangutans, together with Jane Goodall, formed a trio of researchers who laid the foundations of modern primatology and forever changed how we view great apes.

Of these three trailblazing women, often referred to as the “trimates,” Biruté Galdikas is the last surviving member. Born in 1946, this Canadian primatologist has devoted her life to studying and advocating for orangutans—and their habitat, which is being devastated by deforestation. She founded an organization in 1986 and tirelessly condemns the destruction caused by palm oil plantations. In an interview with Decatur Metro, she looks back on her passionate decades-long struggle in the jungles of Borneo.

Decatur Metro — Jane Goodall passed away on October 1, 2025. What legacy does she leave behind?

Biruté Galdikas — I believe she will never be forgotten. What she did to change people’s perceptions and attitudes towards great apes is extraordinary. She unequivocally demonstrated that chimpanzees are very close to us, not just genetically but also cognitively, emotionally, and behaviorally. She discovered that they use and make tools. They are like us, unfortunately even in the worst ways, capable of violence and genocide.

Jane Goodall was a very energetic, kind, and intelligent person. She never stopped traveling and telling the world about the great apes, thereby enhancing our understanding of ourselves, humans. Her remarkable achievements have been an inspiration and a role model for me when I started my research. I was very fortunate to have known her.

What was known about orangutans when you arrived in Borneo to study them in 1971?

We knew very little, if anything. We didn’t know whether they were social or solitary, whether they preferred eating leaves or fruits, or if they lived in trees or on the ground… We had some scraps of knowledge, but we didn’t understand them.

That’s what I have been trying to address over the past 54 years. We now know that they spend most of their time in trees, primarily feed on fruits, females don’t stray far from where they were born, while subadult males leave their mothers and become nomadic. They bring new genetic material to the females who are less mobile: this is a crucial dynamic in orangutan society. That’s what I discovered there.

What was it like to do science in the middle of a tropical forest in the 1970s, when you arrived without experience?

You take notes and observe as much as possible. I faced numerous diseases: I had malaria, typhoid, cholera, amoebic dysentery, infections. I dealt with leeches, venomous snakes, scorpions, and all sorts of tropical forest hazards. It would have been difficult to survive without antibiotics. At one point, my hands were so infected I couldn’t close them. It was truly terrible.

We endured constant torrential rains. I was soaked. It was cold. I remember wondering how it was possible to shiver from cold so near the equator. It was really very challenging. But I was young and fairly robust, so I survived. I’m very, very glad about that. When I think back to the first 20 or 25 years of my work in the Borneo jungle, I remember being very happy. I was almost daily in contact with orangutans and constantly learning new things.

What was your first encounter with orangutans like?

What struck me first was how difficult they were to follow. The first time I saw one, it was a female with her young. We were by a river. As soon as she saw us, the female started vocalizing then retreated into the depths of a swamp. It was pouring rain; I only caught a brief glimpse of them. I wanted to follow them, but my companions told me we couldn’t go into the swamp. But I realized I would have to if I wanted to follow the orangutans, and I spent a lot of time walking and stumbling in those swamps, with water up to my waist, sometimes up to my neck.

You chose to study these animals “as individuals.” Why adopt this approach, which was not the norm in primatology at the time?

In my book Memories of Eden [Belfond, 1997], I recount how the orangutan Beth quickly got used to my presence. She was very calm, serene, and allowed me to follow and observe her. On the other hand, Cora was quite aggressive, clearly signaling she did not want me to follow her. It soon became apparent that there were significant personality differences among individuals, as Jane Goodall had shown for chimpanzees. She gave me a lot of advice and was very supportive of me.

Jane Goodall, Dian Fossey, and I were able to highlight that there are as many personality differences among great apes as there are among humans, and likely among all animals.

If we want to understand orangutans, not just genetically but in terms of behavior, attitudes, cognition, we need to study them in their natural environment. We can’t understand animals in captivity. If you want to understand humans, you wouldn’t study them in prison. The same goes for orangutans. Field studies in the wild are necessary to understand who each orangutan individual is, thereby gaining an insight into the population and the species.

What major uncertainties still surround our understanding of orangutans?

There are still things to uncover that we don’t even suspect before we discover them. But we must also be aware that orangutans, like humans and all animals, are constantly changing along with their environment. They evolve and adapt: the orangutans in my study area today are not the same as those I observed 54 years ago.

Their forest is shrinking, fragmenting, and disappearing. And they are changing as well. This underscores the value of long-term studies on these animals, which allow us to study these changes.

With the continued destruction of the Borneo forest and the dire situation of orangutans, classified as “critically endangered,” do you remain optimistic?

All we have left is hope. I remain optimistic because we must keep hoping. Seeing many young people embracing the ecological cause makes me happy and gives me courage. And I believe one reason people are starting to change is the growing realization that our species is not unique. The more people understand that humans are not unique, that we are just one creature among many on this planet and that we are part of nature, the more progress we will make.

We think we are unique because we have powerful technology, but with wildfires, floods, and all these disasters, nature proves it is the strongest. If we want to survive as a species, it’s time to remember that we are part of it. It’s a very simple idea, which has seemed strange since the Industrial Revolution, but which Aboriginals and many other indigenous peoples understand very well. And which traditional peoples in Europe also understood very well. Understanding that we are part of nature, and respecting it, is the only rational thing left to do.