Why Monkeys Matter: What I’ve Learned From Finding Poop in the Woods

Ph.D. candidate Jackson Frechette has just concluded 14 months of gibbon field research with CI in the forests of Cambodia. Today on Human Nature, he shares why this work is so important. Although it should be noted that gibbons are actually not monkeys, but “lesser apes,” this is the third post in our “Why Monkeys Matter” series.
In May 2011, I arrived in Cambodia to conduct my Ph.D. research on gibbons in Veun Sai Siem Pang Conservation Area (VSSPCA). I had no idea what to expect.
I had never been to Cambodia; in fact, it was just eight months prior that I had switched my research site from South America. Until that point, I had spent my entire career working in and studying South American ecosystems. I even lived for 13 months in the jungles of Suriname studying capuchin monkeys.
But the opportunity to study gibbons and work with CI was too enticing to pass up. So here I was, entering an unknown world, leaving behind my culture, my language and my girlfriend for over a year.
The first thing almost every Western visitor says upon arriving at the site is: “This is the most remote place I have ever been.” It’s that remoteness, about one and a half days of travel from Phnom Penh, which makes this area one of the great wild places on Earth.
After traveling two hours from Ban Lung (the nearest city) by motorbike through rice paddies and forest fragments, you arrive at base camp in the conservation area — 55,000 hectares (136,000 acres) of forest interspersed with patches of open savanna.
Thirty years ago, this place had tigers, elephants, and other large animals roaming wild. Today it is still home to a number of amazing creatures, including a very healthy population of amazingly beautiful and threatened red-shanked doucs, a monkey known for its colorful appearance. The VSSPCA also hosts the largest population of a newly discovered and endangered species of gibbon called the northern yellow-cheeked crested gibbon (Nomascus annamensis).
My research focus is to understand the importance of primates to the environment. Specifically, I am studying the role of northern yellow-cheeked crested gibbons as seed dispersers. The goal is to learn the importance of gibbons in maintaining the health of forests by dispersing seeds.
To do this I spent months following our one “habituated” group of gibbons — a group that has become used to the presence of the researchers and generally ignore us. Almost every day I would wake up at 4 a.m. in order to reach the gibbon group in time for their dawn singing, and follow them until they went to bed around 4 p.m. While following them my field assistants and I would document the gibbon’s behavior, diet and location throughout the day.
To understand gibbon’s role in seed dispersal, I needed to determine where the gibbons “dispersed” (i.e., pooped) the seeds of the fruit they had eaten. Every time a gibbon pooped, I would mark the location with a GPS and count the number of seeds of every species of plant in the stool.
As I sat under fruiting trees, I also watched birds eat the same fruits and documented where they dispersed the seeds. This helped me compare how gibbons and birds, the two major dispersers, differ in their contribution to the tree’s overall seed dispersal pattern.
So how are gibbons important to trees? Not in the way you might expect.
It appears that birds disperse more seeds, and the closer those seeds are to the source tree. the higher the rate of germination and survival as a seedling. Gibbons are important because they disperse seeds far away from the source tree (by defecating the seeds up to two days after eating the fruit). Long distance is extremely important for plants because the few seeds that do survive and grow into adult trees colonize new habitats and help maintain genetic health by breeding with distantly related individuals.
It’s clear that maintaining VSSPCA and Cambodia’s other remaining intact forests is essential for the long-term well-being of the country’s people. These protected areas provide ecosystem services essential to the human population, including fresh water, fibers, building materials, carbon sequestration and much more.
Unfortunately, the pressures of a developing world hungry for luxury wood and wildlife products are catching up to VSSPCA. Such areas are rapidly declining in a country threatened by one of the worst deforestation rates in the world. In the past 40 years, Cambodia’s primary rainforest cover has decreased from over 70% in 1970 to a mere 3.1% remaining today, and this rate continues to accelerate.
Locally, the protection of VSSPCA and the unique and rich biodiversity within it is beginning to improve the livelihoods of some of Cambodia’s poorest people, and has already brought needed jobs to the area. Last year, CI helped launch an ecotourism program centered on the gibbons, forest and indigenous people that have lived here for generations. It aims to bring sustainable livelihoods to the community, raise national awareness and support improved protection of VSSPCA.
Our hope is that through increased law enforcement efforts and conservation initiatives like ecotourism we can save some of the last remaining wildlife habitat in Asia.
Jackson Frechette is a Ph.D. candidate in the Interdisciplinary Ecology program at the University of Florida. He just returned from Cambodia after living and working with CI in VSSPCA for the last 14 months. He plans to continue working in the area on primates and conservation after he graduates next year. To learn more about Jackson’s work and VSSPCA, visit his website. Read more posts in the “Why Monkeys Matter” series.