Mountain gorillas are one of conservation’s great comeback stories. Forty-odd years ago there were only around 250 left. Today there are just over a thousand, and every one of them lives in a small area of forest where Uganda, Rwanda and DR Congo meet. Here’s what makes them so special.
Who they are
The mountain gorilla, Gorilla beringei beringei, is a subspecies of the eastern gorilla. Its thick, long fur helps it cope with the cold, wet forests where it lives, often at high altitude. Like us, gorillas are great apes, and each one can be recognised by its unique “nose print”: the pattern of wrinkles around the nostrils that researchers use to identify individuals.
Biology in brief
- Size: adult males weigh roughly 120–190 kg; females are much smaller, at around 70–100 kg.
- Diet: almost entirely plants: leaves, shoots, stems, bark and, in Bwindi, more fruit than in the Virungas. Researchers have recorded well over a hundred food plants.
- Nests: every gorilla builds a fresh nest of leaves and branches each evening, on the ground or in low vegetation. Trackers use last night’s nests to find the family each morning.
- Babies: a female usually gives birth to a single infant after a pregnancy of around eight and a half months, and typically only every few years, which is why populations grow slowly.
- Gentle by nature: despite their strength, gorillas are generally calm and peaceful. Chest beating is mostly display and communication.
Families and silverbacks
Mountain gorillas live in family groups that usually number from about five to thirty, averaging around ten. Each group is led by a dominant adult male, the silverback, named for the saddle of grey or silver hair that develops across his back as he matures. Some groups have more than one silverback, with younger males lower in the hierarchy.
The silverback decides when the group moves, feeds and rests, settles squabbles, and protects the family from rival males and other threats. When they grow up, most males and many females leave the group they were born into, either to join another family or, for males, to travel alone until they can form a group of their own.
How many are left?
The most recent complete figures give a world population of about 1,063 mountain gorillas: 604 in the Virunga Massif (2015–16 census) and 459 in the Bwindi–Sarambwe ecosystem (2018 census). In 2018 the IUCN moved the mountain gorilla from Critically Endangered to Endangered, thanks to decades of protection, veterinary care and tourism funding.
A new genetic census of Bwindi and neighbouring Sarambwe in DR Congo began in May 2025. At the time of writing, the Uganda Wildlife Authority says the samples are still being analysed, so the updated total isn’t available yet. We’ll update this page when it is published.
Where they live
- Uganda: Bwindi Impenetrable National Park, home to roughly half the world’s mountain gorillas, and Mgahinga Gorilla National Park on the Virunga volcanoes.
- Rwanda: Volcanoes National Park, where Dian Fossey founded the Karisoke Research Center in 1967.
- DR Congo: the Mikeno sector of Virunga National Park, where access depends on the security situation.
The threats they still face
- Human diseases: gorillas can catch our colds and flu, which is why anyone who is unwell is turned away from a trek.
- Snares: set for antelopes, they can still maim gorillas.
- A tiny range: with so few animals in so small an area, a single disease outbreak or conflict could do great harm.
Good to know
- Visitors spend one hour with a habituated family, in groups of up to eight people. The minimum age is 15.
- Your permit fee directly funds rangers, research and local communities.
- For everything else, see our gorilla trekking FAQs and permit prices for 2026–2027.
Meet them for yourself
Watching a silverback feed while infants tumble around him is something visitors never forget, and every trek helps keep these gorillas safe. Tell us your dates and we’ll secure permits in Bwindi, Mgahinga or Rwanda and plan the rest of your trip around them.
