Endangered Despite Recovery
The mountain gorilla’s journey from approximately 254 individuals in 1981 to over 1,000 today is one of conservation’s greatest achievements. Yet the species remains listed as Endangered by the IUCN, and the threats that brought gorillas to the brink have not disappeared — they have evolved. Understanding what specifically endangers mountain gorillas today, and how effectively current conservation efforts address those threats, is essential context for anyone who cares about the species’ long-term survival.
Disease Transmission from Humans
The single most immediate and constant threat to mountain gorillas is disease transmitted from humans. Gorillas and humans share approximately 98% of their DNA, which means that pathogens evolved to exploit human biology can, and do, infect gorillas. The consequences can be fatal: respiratory viruses that cause mild colds in humans can trigger pneumonia and death in gorillas whose immune systems have not evolved specific defences against those pathogens.
The COVID-19 pandemic demonstrated this vulnerability acutely. In 2021, gorillas at the San Diego Safari Park became the first great apes to test positive for SARS-CoV-2, catching the virus from asymptomatic human caregivers. In the wild, COVID-19’s spread to mountain gorilla populations would be potentially catastrophic in a population of only 1,063 individuals. Uganda and Rwanda suspended gorilla tourism during peak COVID-19 periods specifically to prevent transmission.
The seven-metre minimum distance rule during trekking, mandatory masking for visitors in some parks, and pre-trek health screening are all direct responses to the disease transmission threat. These protocols reduce but cannot eliminate transmission risk — habituated families have regular contact with rangers who monitor them daily, and even small exposures over time create cumulative risk.
Habitat Loss and Fragmentation
Mountain gorilla habitat is surrounded by some of the most densely populated farmland in Africa. Uganda, Rwanda, and the DRC all have high rural population densities in the areas bordering gorilla parks. Agricultural expansion into park boundaries, illegal crop cultivation within forest margins, and charcoal production from forest trees all reduce the effective habitat available to gorillas.
In Bwindi, the park boundary is immediately adjacent to farmland in most sectors. The buffer zone between the park and cultivated land is minimal or absent in places, and gorillas regularly cross the boundary to raid crops — a human-wildlife conflict that generates resentment and occasionally results in gorillas being killed or injured by farmers protecting their livelihoods. Community benefit-sharing programmes that give local people a financial stake in gorilla protection have reduced this conflict significantly, but not eliminated it.
Climate Change
Climate change represents a growing long-term threat to mountain gorillas whose impact is not yet fully measurable. Temperature increases at high altitudes may shift the distribution of food plants that gorillas depend on, potentially forcing the animals to higher elevations where suitable habitat becomes progressively scarcer. Altered rainfall patterns may reduce the moisture content of vegetation, affecting gorilla hydration strategies and food availability across dry seasons.
Climate models project that the suitable habitat range for mountain gorillas could contract significantly by 2080 under high-emission scenarios. The two gorilla populations, already geographically isolated from each other, would face further range compression that could force them into even smaller areas and reduce their already limited genetic diversity.
Political Instability and Armed Conflict
The Virunga population of mountain gorillas — approximately 600 individuals in the volcanic highlands shared by Uganda, Rwanda, and DRC — is particularly vulnerable to political instability. Eastern DRC has experienced continuous armed conflict since the 1990s, and Virunga National Park, which protects the largest portion of the Virunga gorilla population, has been caught in the conflict multiple times.
In 2018 and subsequent years, armed group activity forced the suspension of gorilla tourism in Virunga, eliminating the revenue that funded ranger protection. Several park rangers have been killed protecting gorillas from armed groups. The gorillas themselves face elevated poaching risk during periods when ranger presence is reduced, and the forest may be used by armed groups who cut trees, hunt bushmeat, and displace local communities — all activities that indirectly threaten gorilla habitat and food security.
Poaching
Direct poaching of mountain gorillas for meat or the pet trade has been dramatically reduced through intensive anti-poaching efforts, but it has not been eliminated. In 2020, Rafiki, one of Uganda’s most famous silverbacks and the leader of the Nkuringo family group, was killed by poachers using spears. His death highlighted that despite improved security and community engagement, individual animals remain vulnerable to determined poaching.
Gorillas are also killed incidentally in snares set for other animals. Anti-snare patrol teams in Bwindi and other gorilla parks remove thousands of snares annually, but the frequency of snare injuries in gorilla families — requiring veterinary intervention — demonstrates that this threat remains active and ongoing.
Inbreeding and Genetic Diversity
With only 1,063 mountain gorillas in two isolated populations, inbreeding is an inevitable long-term concern. Genome analysis has confirmed that both Bwindi and Virunga populations show reduced genetic diversity consistent with small population sizes and periodic bottlenecks. Reduced genetic diversity limits a population’s capacity to respond to new diseases, environmental changes, and other evolutionary challenges.
The geographic isolation of the two populations — separated by tens of kilometres of farmland — prevents natural genetic exchange. No programme currently exists to facilitate genetic mixing between the populations, partly because the risks of disease transmission during any such translocation programme would need to be weighed very carefully against the genetic benefits.
Final Thoughts
Mountain gorillas face threats on multiple fronts simultaneously: disease, habitat loss, climate change, conflict, poaching, and genetic isolation. The conservation system that has produced the population’s remarkable recovery addresses most of these threats in real time. But addressing them requires sustained funding, political commitment, and international attention. Every gorilla permit purchased contributes to a system that is, day by day, keeping these animals alive against genuinely serious odds.
