(August 2006) The chimpanzees of Gombe National Park in Kigoma Region, Tanzania, have come under increased pressure from four decades of high human population growth in the region and an associated increase in human activity and disease. The result has been a steady decline in the chimpanzee population residing in Tanzania's smallest national park, from 150 chimpanzees in the 1960s to about 90 today (see Why the Chimpanzees of Gombe National Park Are in Jeopardy).
The dramatic decline in the Gombe chimpanzee population is largely due to a significant reduction in suitable forested habitat for the great apes. With more people living around the national park, surrounding forests have been cleared to make way for houses and farms, reducing the national park to a 35 square-kilometer island forest.
Human-to-animal (zoonotic) disease transmission is another reason for worry. Although tracing a disease's origin back to a specific host can be extremely difficult, scientists working in African national parks such as Gombe, Kibale (in Uganda), Parc de Volcans (Rwanda), and Bwindi Impenetrable Forest (Uganda) believe that humans are most likely the transmitters of diseases such as polio, pneumonia, measles, and scabies, which have affected the parks' respective ape populations over the past four decades.
Park staff, scientists, and locally based organizations are working to find solutions to a difficult problem: Can humans and chimpanzees coexist so that communities are able to maintain their livelihoods without compromising chimpanzees' health and habitat requirements? Several actions to help protect chimpanzees against further population decline have already been taken. These steps include:
- Limiting the number of tourists each day who are allowed to observe chimpanzees;
- Addressing the health and livelihood needs of local communities through community development projects;
- Conducting conservation outreach and education programs; and
- Maintaining ongoing scientific research efforts.
Other recommended solutions have not yet been implemented, including: establishing conservation employee-health programs in all great ape protected areas; enforcing stricter rules regarding tourists and park personnel's contact with chimpanzees; and mobilizing the international conservation community, including the United Nations, to develop and enforce stronger and more-effectve protection policies for the remaining great ape populations across sub-Saharan Africa.
Reducing the Risk of Zoonotic Disease Transmission
Tourists and Conservation Workers
There may be several inexpensive ways that human-to-animal disease transmission can be reduced in protected areas. Recommendations from the authors of a study carried in Kibale National Park in Uganda—which suggests that chimpanzee populations there are exposed to human diseases through regular contact with both tourists and local residents—included educating tourists regarding appropriate vaccinations, requiring handwashing prior to entering chimpanzee habitats, using facemasks during sighting visits, and restricting the number of visitors allowed in the protected area.
Matatu Mushi, chief park warden in charge at Gombe National Park, says that Gombe can accommodate up to 1,500 tourists per year—but that he prefers to maintain the current average annual of 700 to 800 visitors. "Gombe is the most expensive national park in Tanzania to visit [for a park permit], and I'm glad of it," Mushi says. "The fewer the visitors, the less the risk of disease transmission."
Conservation employees are another group that has been identified as a potential threat to chimpanzee health due to their close exposure—sometimes on a daily basis—to great apes. In Gombe, for example, both researchers and park personnel often live inside the park boundaries and occasionally have direct contact with chimpanzees.
The Great Apes/Human Health Working Group—part of the World Conservation Society's Animal Health for the Environment and Development (AHEAD) initiative—has stated that "protecting [park] employee health should be considered a 'critical control point' in terms of protecting the health of wildlife," including conservation programs for wild apes.1 Such employee health programs would provide preventive steps (vaccinations and health education), clinical assessment, and case management services to all protected-area conservation employees.
Of course, tourists and conservation employees are not the only potential source of disease—local residents also pose a threat to the health of the Gombe chimps. Like most local communities that border protected areas in developing countries, the rural Kigoma villages bordering Gombe National Park have limited access to health services and information due to their remote location and limited human and financial resources.
In areas such as these, health education can be a powerful conservation tool, potentially bringing together the public health, conservation, and tourism sectors. Such an intervention was implemented in villages around Bwindi Impenetrable National Park in Uganda after consecutive scabies disease outbreaks in mountain gorillas occurred there in 1996 and 2000.2
Scientists believed that gorillas were infected by exposure to contaminated clothing, uncovered rubbish heaps, and shallow pit latrines—problems that the communities themselves realized needed to be addressed. After a series of health education workshops and a successful information campaign conducted by the Uganda Wildlife Authority and local leaders, local residents indicated that they had seen an improvement in the public health conditions of their communities—and since 2002, there have been no reported scabies outbreaks in Bwindi's gorilla population.
Conserving Forests Through Family Planning and Sustainable Livelihood Practices
Other groups are working to provide sustainable livelihoods for humans living near the park. Based in Kigoma, the Jane Goodall Institute's Lake Tanganyika Catchment, Reforestation, and Education (TACARE) Project has served more than 200,000 people in the area around Gombe National Park. TACARE's efforts and successes are many: providing family planning information and contraceptives, introducing fuel-efficient stoves, helping to supply several villages with reliable sources of water and improved sanitation, and providing training and support for the establishment of village-level savings and credit schemes.
"We have noticed that women who are involved in the microcredit programs and have started small businesses are more likely to adopt family planning," says Sania Lumetezi, head of the health section at TACARE. "All of a sudden their time becomes more valuable, they are more self-confident, and they desire more control over their fertility."
Recognizing that slowing population growth is a long-term undertaking, TACARE also conducts regular conservation outreach activities in local communities—providing training, support, and supplies to farmers who adopt more environmentally sustainable agricultural practices such as contour farming, planting native grasses on slopes susceptible to erosion, and planting multipurpose trees.
"All of the TACARE staff have committed 100 percent to implementing a holistic approach to sustaining the environment, health, and livelihoods of the area's residents," says Mary Mavanza, TACARE's project manager.
Gombe National Park staff are also working with local communities through its Community Conservation Services outreach program to improve conservation awareness and to support local schools and health dispensaries. Park staff work continuously to improve trust and cooperation between the communities and the park. The importance of this relationship is not lost on Mushi. "Without the communities' cooperation," he says, "Gombe will not succeed."
Calls for a Global Survival Strategy for the Great Apes
Greater cooperation is needed at the international level as well. Since 2001, great ape conservation efforts have been coordinated by the Great Ape Survival Project (GRASP), which brings together representatives of the 23 countries with great ape populations, the UN Environment Programme, and some NGOs. But while some significant efforts have already been made, these initiatives have not been sufficient to safeguard great apes from the relentless pressures—deforestation, disease, and illegal poaching—that have led to the continued decline in both their numbers and distribution.
GRASP has indicated the need for the "development and implementation of a global survival strategy for all great ape populations within their dynamic, evolving natural ecosystems." Current piecemeal conservation efforts would have greater impact, the project argues, if efforts were integrated within a systematic approach to a globally defined problem while being tailored to local circumstances.3
Stabilizing the Situation
Although Gombe National Park faces formidable challenges, analysts are somewhat optimistic that the chimp population can survive. The Population and Habitat Viability Analysis (a computer-simulation exercise based on certain assumptions about chimpanzees' fertility, mortality, and other variables) shows that—barring any catastrophes, and despite a decline in the chimpanzee population over the next 50 years—Gombe chimps have a chance at survival for at least the next 100 years.
But with some experts predicting extinction of great apes—including chimpanzees—over most of their current range in sub-Saharan Africa during the next 10 to 20 years, saving the chimpanzees of Gombe will require tremendous effort.4 Conservation and development programs must be effectively implemented, human population growth rates around the park must be stabilized, the park must earn and maintain the trust and cooperation of local communities, and the park must nurture its strong relationship with local and international organizations and research institutions.
"Although knowing that the chimp population is likely to continue to shrink here is saddening, on the other hand, the results do give us hope," says Mike Wilson, director of field research at the Gombe Stream Research Center and the scientist who oversaw the Population and Habitat Viability Analysis. "We can still do something to save the chimpanzees of Gombe so they don't disappear altogether."
Melissa Thaxton is a policy analyst at the Population Reference Bureau.
- Wildlife Conservation Society, Animal Health for the Environment and Development (AHEAD), and Great Apes/Human Health Working Group, Consensus Document Outlining Practical Considerations for Reducing Health Risks to African Great Apes and Conservation Employees Through an Occupational Health Program (2005), accessed online at www.wcs-ahead.org, on July 27, 2006.
- Gladys Kalema-Zikusoka, "Protected Areas, Human Livelihoods and Healthy Animals: Ideas for Improvements in Conservation and Development Interventions," in Conservation and Development Interventions at the Wildlife/Livestock Interface: Implications for Wildlife, Livestock, and Human Health, ed. Steven A. Osofsky (Gland, Switzerland: IUCN, 2005).
- Great Apes Survival Project (GRASP), Global Strategy for the Survival of Great Apes and Their Habitat (Nairobi: UNEP, 2005), accessed online at www.unep.org, on July 28, 2006.
- "The Current Condition of Great Apes in the Natural Environment," Pan Africa News 1, no. 8 (2001), accessed online at http://mahale.web.infoseek.co.jp/PAN/8_1/8(1)-05.html, on June 30, 2006.