The mountain gorilla (Gorilla beringei beringei) is one of the rarest great apes on Earth, with approximately 1,063 individuals surviving in the wild. About 459 live in Bwindi Impenetrable National Park, making Buhoma one of the best places on the planet to encounter these extraordinary primates. Mountain gorillas exist nowhere in captivity — the only way to see them is in their natural forest habitat.
Quick Facts
- Scientific Name:
- Gorilla beringei beringei
- Wild Population:
- ~1,063 individuals
- Bwindi Population:
- ~459 individuals
- IUCN Status:
- Endangered (upgraded from Critically Endangered in 2018)
- Adult Male Weight:
- 140–200 kg (310–440 lbs)
- Lifespan:
- 35–40 years in the wild
- Diet:
- Herbivorous — leaves, stems, shoots, bark, bamboo
- DNA Similarity to Humans:
- 98.3%
- Group Size:
- 5–30 individuals
- Gestation Period:
- 8.5 months
Discovery and Taxonomy
Mountain gorillas were unknown to Western science until October 17, 1902, when German military officer Captain Friedrich Robert von Beringe shot two large apes on the slopes of Mount Sabinyo in the Virunga Mountains (then German East Africa). One specimen was later described as a new subspecies and named Gorilla beringei in his honour.
Today, mountain gorillas are classified as Gorilla beringei beringei, one of two subspecies of the eastern gorilla. Their closest relatives are Grauer's gorillas (Gorilla beringei graueri), larger-bodied lowland dwellers found in eastern Democratic Republic of Congo. Together, eastern gorillas are distinct from the western gorillas (Gorilla gorilla) of West and Central Africa, from which they diverged roughly 1.75 million years ago.
Mountain gorillas are adapted to life at high altitude — between 1,400 and 3,800 metres above sea level. Their thicker, longer fur distinguishes them from lowland populations and is an adaptation to the cold, moist climate of the Afromontane forests they inhabit.
Physical Characteristics
Silverbacks
Adult males are called silverbacks for the distinctive saddle of silver-grey hair that develops across their backs and hips around age 12-13, marking full sexual maturity. A silverback can weigh up to 200 kg, with an arm span reaching 2.3 metres. Their sagittal crest — a bony ridge along the top of the skull — anchors powerful jaw muscles capable of crushing tough vegetation like bamboo and bark.
Silverbacks are the undisputed leaders of their groups. They determine the daily travel route, mediate conflicts, protect the family from threats, and are the centre of social life. When a silverback dies, the group typically disintegrates unless another mature male is ready to assume leadership.
Females and Young
Adult females weigh roughly half as much as silverbacks — 70 to 115 kg. They reach sexual maturity around age 8 and typically give birth for the first time at 10. The gestation period is 8.5 months, and infants weigh about 1.8 kg (4 lbs) at birth — tiny compared to their parents.
Infant gorillas are carried by their mothers for the first 2-3 years and are weaned at about age 3.5. Young gorillas are playful and curious, often tumbling, wrestling, and swinging from branches in ways that are strikingly reminiscent of human children. Females typically produce only 4-6 offspring in their lifetime, with intervals of about 4 years between births — a slow reproductive rate that makes population recovery challenging.
Behaviour and Social Structure
Mountain gorillas live in stable family groups typically numbering 5 to 30 individuals. Each group is led by a dominant silverback whose authority is rarely challenged by group members. Groups may contain multiple silverbacks — usually sons or younger brothers of the dominant male — who occupy subordinate roles and may eventually inherit leadership or break away to form their own groups.
A typical gorilla day follows a predictable rhythm. The group wakes at dawn (around 6:00 AM), feeds intensively during the cooler morning hours, rests during the midday period — when adults nap and youngsters play — then feeds again in the afternoon before constructing night nests from bent vegetation around 6:00 PM. Each gorilla builds a fresh nest every evening, and these abandoned nests are one of the key tools rangers use to locate groups.
Communication among gorillas is rich and complex. Researchers have catalogued at least 25 distinct vocalisations, including deep “belch vocalisations” (contentment grunts given during feeding), alarm barks, screams, and the iconic chest-beating display. Chest-beating — performed primarily by silverbacks — serves as long-distance communication, advertising the male's size, strength, and location to other groups and potential rivals.
Despite their formidable appearance, mountain gorillas are overwhelmingly peaceful. Aggressive interactions between groups or individuals are rare and usually limited to displays rather than actual physical contact. Gorillas share 98.3% of their DNA with humans and display behaviours that appear to reflect grief, empathy, playfulness, and problem-solving intelligence.
Diet and Feeding
Mountain gorillas are almost exclusively herbivorous. Their diet includes the leaves, stems, pith, bark, and shoots of over 140 plant species. In the Bwindi population, the most important food plants include species of Basella, Urera, Myrianthus, Brillantaisia, and wild celery (Peucedanum linderi). Gorillas in higher-altitude areas consume significant quantities of bamboo shoots when available.
The Bwindi population is notable among mountain gorillas for its greater consumption of fruit — a dietary adaptation to the lower altitude and more diverse forest of Bwindi compared to the Virunga volcanoes. When fruiting trees are productive, Bwindi gorillas may travel farther in a day to access these preferred food sources, which are higher in sugar and energy.
An adult male mountain gorilla can consume up to 34 kg (75 lbs) of vegetation daily. Despite this prodigious intake, gorillas are not destructive feeders — they carefully select specific plant parts and typically leave enough for regrowth. Their feeding activity actually helps maintain forest structure by opening small gaps in the canopy and dispersing seeds.
Conservation History
The story of mountain gorilla conservation is one of the great wildlife recovery narratives. By the mid-1980s, the total population had fallen to an estimated 620 individuals. Habitat destruction, poaching, political conflict, and disease threatened the subspecies with extinction.
Dian Fossey was pivotal in changing the gorillas' trajectory. The American primatologist established the Karisoke Research Center in Rwanda's Virunga Mountains in 1967 and spent 18 years studying gorilla behaviour and fighting poaching. Her research revealed the gorillas' gentle nature and complex social lives, overturning popular perceptions of them as fearsome beasts. Her 1983 book Gorillas in the Mist and the 1988 film adaptation mobilised global public support for gorilla conservation. Fossey was murdered at Karisoke in December 1985, a crime that remains officially unsolved.
In Bwindi, gorilla-based tourism began in 1993 when the Mubare group — the first family habituated in the park — received its first tourist visitors near Buhoma. This pioneering programme demonstrated that gorillas could generate substantial revenue through tourism, creating powerful economic incentives for conservation. The model has been replicated across all gorilla range states.
Today, decades of sustained conservation effort have produced remarkable results. The mountain gorilla population has grown from approximately 620 in 1989 to over 1,063 — a 72% increase. In 2018, the IUCN reclassified the subspecies from Critically Endangered to Endangered, the first such improvement in status. This recovery is attributed to intensive veterinary care, anti-poaching patrols, community engagement, and the economic benefits generated by gorilla tourism.
However, the species remains vulnerable. Mountain gorillas cannot survive in captivity, occupy a tiny geographic range, and face ongoing threats from disease (they are susceptible to many human illnesses), climate change, and the political instability that periodically afflicts the region. Continued conservation investment and responsible tourism remain essential.
Gorilla Families of Buhoma
Buhoma was the first sector of Bwindi to open for gorilla trekking and remains the most popular and accessible starting point. Several habituated gorilla families can be tracked from the Buhoma trailhead, with group assignments varying as families move through their home ranges and new groups are habituated.
The Mubare group holds a special place in Bwindi's history as the very first gorilla family habituated for tourism in the park, beginning in 1991 and receiving visitors from 1993. Named after Mubare Hill where they were frequently found, this group has been the subject of extensive research and has contributed enormously to our understanding of Bwindi's gorilla population dynamics.
Other families accessible from Buhoma have included the Habinyanja group (habituated in 1997), the Rushegura group (which split from Habinyanja), and additional groups as the park's habituation programme has expanded. Each family has its own personality, shaped by the temperament of its silverback leader and the family's history.
Related Pages
Gorilla Trekking
Plan your gorilla trekking experience — permits, preparation, what to expect, and practical tips.
Primates of Bwindi
Discover all 13 primate species found in Bwindi, from chimpanzees to nocturnal bushbabies.
Community Conservation
How gorilla tourism funds conservation and supports communities around Buhoma.