Posted on May, 06 2025

6 May 2025, Bwindi, Uganda: − Greater Virunga Transboundary Collaboration (GVTC) in collaboration with partners have begun a new count of mountain gorillas (Gorilla beringei beringei) in Bwindi, Uganda. ¹
Launched today, the new scientific count will provide a robust estimate of the number of mountain gorillas living in Bwindi, and an indication of how the population has changed since the previous census was carried out in 2018.

Bwindi – Sarambwe is one of the two natural habitats on earth where mountain gorillas can be found. The 2025 Bwindi-Sarambwe population survey of mountain gorillas is led by IGCP, a coalition of three leading conservation organizations; Conservation International, Fauna & Flora and WWF, and will be carried out collaboratively by scientists and national park authorities under the transboundary framework of the Greater Virunga Transboundary Collaboration.
 
The 2018 Bwindi-Sarambwe census resulted in an estimate of 459 individuals in 36 social groups and 16 solitary mountain gorillas. Together with the Virunga census results of 2015, the Bwindi census results of 2018 brought the global total population of mountain gorillas to 1,063 individuals.
 
In 2018, the threat status for mountain gorillas was downgraded from ‘Critically Endangered’ to ‘Endangered’ in the IUCN Red List of Threatened Species due to the recorded increase in their population as demonstrated by repeated census operations.  This major success is the result of decades of dedicated conservation efforts (more here).
 
The new Bwindi - Sarambwe census will also provide information on demographics (age and sex ratio) within the Bwindi – Sarambwe population, and the location of groups in relation to each other within the ecosystem, on illegal activities, vegetation dynamics in the gorilla habitat, and the status of other large mammals.
 
“It is always an honor for IGCP to spearhead the mountain gorilla census process. Working closely with the mountain gorilla range countries and other partners, we look forward to delivering a comprehensive Bwindi census that will contribute to the conservation of mountain gorillas,” says Wellard Makambo, IGCP Director.

The Bwindi - Sarambwe census will also include the first ever count of chimpanzees in the landscape. Commenting on the chimpanzee census happening concurrently, James Byamukama, Executive Director, Director, Jane Goodall Institute Uganda says, “The count of chimpanzees in the Bwindi – Sarambwe landscape, led by the Jane Goodall Institute, is going to be the first ever to determine the population of chimpanzees in this ecosystem, changing the conservation story and branding of Bwindi - Sarambwe as the only landscape with two endangered great apes of mountain gorillas and chimpanzee co-existing with another great ape, the human being”.

Six teams comprising staff from the 11 participating institutions have begun systematically moving on foot through Bwindi, looking for signs of mountain gorillas, recording mountain gorilla nest sites⁴, and collecting fecal samples to be used for genetic analyses. Unlike previous censuses, where samples were shipped abroad for analysis, genetic analysis for this new census in Bwindi – Sarambwe will be carried out within the region. This will not only reduce logistics for shipping samples but also contribute to local capacity building in terms of equipment and personnel.

“The census is a true testament to the strength of collaboration, which has been at the heart of efforts to save the endangered mountain gorillas” explains Dr. Andrew Sseguya, Executive Secretary of the Greater Virunga Transboundary Collaboration.
 
Data and sample collection and analyses will continue through 2025 and results from the count will be released in 2026. 
 
According to Nelson Guma, Chief Park Warden for Bwindi - Mgahinga conservation area in Uganda, this census means a lot for Bwindi and for Uganda at large. “It is an important exercise that measures our success in conserving the endangered mountain gorilla as a flagship species for our protected areas. It will also tell us about the integrity of the protected areas as critical habitats for survival of the endangered mountain gorillas. It is further an opportunity to share our experiences of conducting the mountain gorilla census and enhance methodologies that can be adopted by other gorilla range states as a best practice. The results will be significant for planning and enhancing strategies for sustainable gorilla conservation,” says Nelson Guma.
 
- Ends -
For more information please contact:
 
Alice Mbayahi|IGCP|+256 782 689571|ambayahi@igcp.org
Juvenal Mukeshimana| GVTC |+250788319555|jmukeshimana@greatervirunga.org
 
Notes to Editors:

1. Mountain gorilla (Gorilla beringei beringei) is one of two subspecies of the eastern gorilla (Gorilla beringei). The other is the Grauer's gorilla (Gorilla beringei graueri), also known as the eastern lowland gorilla, this subspecies inhabits the lowland rainforests of eastern DRC.
2. The Bwindi-Sarambwe ecosystem encompasses the Bwindi Impenetrable National Park of approximately 331 km² in Uganda and the Sarambwe Nature Reserve of 9 km² in the Democratic Republic of Congo.
3. Initiated informally by the Park Managers to monitor the Migratory Mountain Gorillas between Democratic Republic of Congo (DRC), Rwanda and Uganda in 1990, the Greater Virunga Transboundary Collaboration has evolved since then into a Treaty signed between the three Partner States in October 2015 as framework of programmes, plans and activities to conserve a network of transboundary Protected Areas in Greater Virunga Landscape (GVL).
4. The mountain gorilla is currently classified by IUCN Red List of Threatened Species^TM as Endangered. http://www.iucnredlist.org/details/39999/0 
5. Each night, mountain gorillas prepare fresh nests of living vegetation in which they sleep. The number of nests in an area gives an indication as to the number of individual gorillas in a group.
6. The census is funded by generous contributions from several partners including WWF, Great Virunga Transboundary Collaboration and Partners in Conservation, range states and local stakeholders through in-kind support.
7. Other institutions supporting and participating in the census include Max Planck Institute for Evolutionary Anthropology (MPI), The Dian Fossey Gorilla Fund (DFGF), Institute of Tropical Forest Conservation (ITFC), Gorilla Doctors/Mountain Gorilla Veterinary Project (MGVP), Conservation Through Public Health (CTPH), Wildlife Conservation Society (WCS), WWF Uganda Country Office, Bwindi Mgahinga Conservation Trust (BMCT), and Primate Expertise (PEx).