Top and left: courtesy of Craig Sholley; Right: Courtesy of AWF/IGCP
Next to chimpanzees, gorillas are the closest living human relatives. Yet, humans have loved, sold, killed, even eaten gorillas. Dian Fossey's popularization of her field work with mountain gorillas in the 1970s "created this global constituency" of support for gorilla research, according to Bill Weber, director of North American programs for the Wildlife Conservation Society (WCS), Bronx, NY.
There are two species of gorillas, each containing two subspecies. Gorilla beringe includes the eastern lowland gorillas (also called Grauer's gorillas) found in the eastern Congo and the mountain gorillas found in the area of the Virunga volcanoes, which are on Congo's and Uganda's border with Rwanda. Gorilla gorilla includes the western lowland gorillas of west-central Africa and the Cross River gorillas.
Thirty years after Fossey--and WCS's George Schaller before her--began studying gorillas, research on the animals continues, although now, Weber says, the emphasis has changed. "There is much more gorilla conservation going on than gorilla research, which is the reverse of what there was 20 years ago." Those working with gorillas face a conundrum, explains Weber. They can be strictly researchers, or they can become involved in conservation projects.
Photo: Courtesy of Craig Sholley
The social and political contexts in which gorillas live render it nearly imperative that people who work with gorillas become heavily involved in conservation. Liz Williamson of the Scottish Primate Research Group, University of Stirling, recently notes, "War and political unrest have had direct impacts on the gorilla population and its habitat, as well as increasing the likelihood of disease transmission from ... people living in the forest under poor conditions of hygiene." Williamson, who formerly headed the Karisoke Research Center in Volcano National Park, Rwanda, studied the behavioral ecology of western lowland gorillas in Gabon for her PhD, and she later censused great ape populations in an area that was then Zaire and in Cameroon. Williamson knows firsthand the threats to gorillas: "During the six years I spent as director of Karisoke, the park was closed for prolonged periods due to insecurity, most notably for two years from June 1997 to July 1999, so much of my time was spent on conservation politics," she wrote in an E-mail.
Primatologist and animal behaviorist Annette Lanjouw, who won the National Geographic Society/Buffett Award for Leadership in African Conservation in August, has stressed studies on habitat use by mountain gorillas, along with ways to conserve both the habitat and the animals while aiding the human communities nearby. Lanjouw, who is director of the International Gorilla Conservation Programme (IGCP), which covers three protected areas in Rwanda, the Democratic Republic of Congo, and Uganda, notes that her group is monitoring gorilla's habitat use. Local rangers collect data on the forest and how gorillas use it; they are especially interested in typical gorilla food species. By knowing this, and also by understanding the needs of people who live near the forest, conservationists can aid in developing "economic patterns more compatible with [conservation]," says Lanjouw. In "both Uganda and Rwanda, we are working with the government to create a buffer zone around [the] park. That buffer zone will be used for providing key resources people can only get inside [the] park; bamboo is an example." Furthermore, developing ecotourism, as the IGCP has done in Rwanda and Uganda, allows tourists to safely and securely see the gorillas in the wild, while adding significantly to the national economy.
Photo: Courtesy of Craig Sholley
"[There's] nothing going on anywhere with eastern lowland or Grauer's gorillas because it's such an unstable area," notes Weber. However, work on lowland and mountain gorillas reveals distinct differences between the two. The mountain gorillas are easier to study because they become habituated to humans and live in an area where the forest is not too dense. Emma Stokes of WCS, who is studying western lowland gorillas with the Mbeli Bai study in Brazzaville, Congo, notes that the species "is notoriously difficult to study in the wild due to problems of habituation and visibility associated with the dense forest vegetation that forms much of its habitat." Unlike other regions, there is no hunting. "It is generally agreed that western lowland gorillas differ from mountain gorillas in certain aspects of their diet and ranging behavior," Stokes says.
Western gorillas feed on seasonal fruit, which is not always available; this creates competition within the groups for food. Similar competition does not often occur among mountain gorillas because they eat herbaceous vegetation available throughout the year, says Stokes. In western lowland gorillas, females tend to move (transfer) from larger groups to smaller groups to decrease the competition. Despite the differences in diet, group transfer of females with infants in both mountain gorillas and western lowland gorillas may result in the new group's silverback (oldest male) killing the infant.
Lanjouw explains the delicate act of balancing research, conservation, and ecotourism: "You've made these animals vulnerable. You've got to continue to protect them."
Myrna E. Watanabe is a freelance science writer in Patterson, NY.