How We Study Gorillas

Dr. Dian Fossey began an historic long-term gorilla study that the Fossey Fund has continued and expanded.  The Dian Fossey Gorilla Fund International conducts scientific research on gorillas and their ecosystems in a number of different ways. Although we are best known for our work with mountain gorillas, the Fund studies both subspecies of eastern gorillas — mountain gorillas, found in Rwanda, the Democratic Republic of Congo (DRC) and Uganda, and Grauer’s (eastern lowland) gorillas, which live exclusively in the eastern DRC. The goal of our research with both subspecies is the same: to learn more about their basic biology and how to best conserve them. However, the methods we use to study mountain and Grauer’s gorillas are different. 

Mountain gorilla research

Mountain gorillas have been studied for over 40 years and many are now habituated to human presence.  As a result, we are able to follow known individuals on a daily basis, recording their behavior in extreme detail.

Each morning, trackers locate their assigned gorilla group by going to their night nest location and then following the trail of crushed vegetation they left behind as they started moving.  After finding the group and recording its location via a global positioning system (GPS), the trackers will find each individual in the group and record information on its general appearance and health as well as detailed information on behavior for our long-term gorilla research database and specific studies.  Individual gorillas are identified through their noseprints. 

Because noseprints can change over the course of an individual’s lifetime, we update our noseprint file each year for each of the more than 110 gorillas we monitor.

Female Turimaso in 2005 at 2 years old (left) and in late 2009

Grauer’s gorilla research

Unlike the mountain gorillas, most of the Grauer’s gorilla populations we work with have never been studied by humans and directly observing them is extremely difficult. Thus, we use indirect methods to learn about their behavior and ecology. For example, we conduct systematic surveys in gorilla habitat, recording all observations of gorillas, such as nests, vocalizations or feces, as well as other large mammals.  Although the gorillas themselves may rarely be seen, we can learn a lot from such data.  For example, nest numbers and their locations recorded via GPS give us an estimate of gorilla distribution and density.  Fecal material can be used to look at the genetic diversity and relatedness of the population, parasite loads and foods consumed.

In the DRC, staff of the community-based nature reserves established over the past decade by local authorities and supported by the Fossey Fund are monitoring gorillas and other wildlife in the areas they protect. Every day, over 80 community rangers use state-of-the art techniques and equipment such as global positioning systems to collect data on the diverse flora and fauna that inhabit the landscape, in particular large mammals such as chimpanzees, buffaloes, elephants, leopards, and okapi, as well as Grauer’s (eastern lowland) gorillas. They also note the animals’ habitats and their dominant plant species, and any human activities in the forest. The data are gathered in a central database and analyzed to track key species and identify threatened areas in the rich Maiko-Tayna Kahuzi-Biega landscape.

Two groups of Grauer’s gorillas are being habituated and studied in the Tayna Nature Reserve, with the goal of enabling in-depth behavioral research similar to the Karisoke™ Research Center’s work in Rwanda.

Collaboration

The Georgia Institute of Technology, Clark Atlanta University, Zoo Atlanta, The Max Planck Institute and the National University of Rwanda are among many educational and scientific institutions that have collaborated with Karisoke™ staff on research projects. Scientists and students from all over the world also come to Karisoke to pursue individual projects. Many students from the National University of Rwanda and other Rwandan post-secondary institutions take field research courses and internships at Karisoke and conduct their dissertation research there with staff supervision.

Students from the Tayna Center for Conservation Biology have presented papers on their research on monkey behavior at the International Primatological Society’s annual convention, with support from the Fossey Fund and its staff.