Mountain gorillas do not recognise international borders. The Virunga Massif — the chain of dormant volcanoes that straddles the borders of Uganda, Rwanda, and the Democratic Republic of Congo — is home to one of the two mountain gorilla populations, and gorillas move through this landscape according to habitat availability and social opportunity rather than political geography. The story of the silverback who crossed from Rwanda’s Volcanoes National Park into Uganda’s Mgahinga Gorilla National Park and established a new family group there is a documented example of this transboundary movement — and of what it means for conservation across three countries.
The Virunga Population and Cross-Border Movement
The Virunga mountain gorilla population — separate from the Bwindi population — numbers approximately 600 individuals distributed across three countries. Their movement through the Virunga landscape is continuous and has been documented by the three national park authorities — Rwanda Development Board, Uganda Wildlife Authority, and Institut Congolais pour la Conservation de la Nature — through a shared monitoring system that tracks habituated groups regardless of which side of a border they happen to be on at any given time.
Solitary males and newly forming groups move the most freely. A male with no established territory and no fixed social obligations can range widely, and the Virunga landscape offers enough continuous forest habitat that the borders between countries are, from the gorilla’s perspective, simply features of the terrain. The male in this account — designated by researchers as a solitary male who had departed the Volcanoes National Park population in Rwanda — crossed into Uganda via the high-altitude bamboo zone that connects the two parks.
The Recruitment of Females
His first interaction with Uganda-based gorillas was with the Nyakagezi group — Mgahinga’s most studied habituated family. He made contact with the group multiple times over a three-month period, displaying at the group’s edge in a pattern that the UWA monitoring team documented as female recruitment behaviour. Two young adult females from the Nyakagezi group eventually transferred to him, establishing the social nucleus of a new group.
The process of habituation for the new group — involving months of gradual, controlled exposure to human presence by UWA rangers — was accelerated by the fact that the two founding females had already been habituated as members of the Nyakagezi group. Their comfort with human proximity was transmitted behaviourally to the silverback and to the infants born into the group in its first years.
What Cross-Border Movement Means for Conservation
The cross-border movement of this silverback and the subsequent establishment of a new group is significant for conservation for several reasons. It demonstrates the genetic connectivity between the Uganda and Rwanda gorilla populations — the male’s genetic material, now represented in the offspring of his group, has moved from one national population to another, maintaining the genetic diversity that small populations require. It also demonstrates that the transboundary conservation framework — the coordination between three countries’ park authorities to manage a single biological population — is functioning as designed.
Visiting Mgahinga in 2027
Gorilla trekking in Uganda at Mgahinga Gorilla National Park offers the opportunity to visit gorillas in the Virunga landscape — a different experience from Bwindi, at higher altitude, with the volcanic peaks visible above the forest. The gorilla permit costs $800 per person. The groups you visit at Mgahinga are part of a transboundary population whose movements connect Uganda, Rwanda, and the DRC. The silverback who crossed from Rwanda to start a family in Uganda did not know he was making conservation history. He was looking for females.
