Mountain gorillas number just over one thousand in the wild. Western lowland populations have declined 60 percent in recent decades. These figures vary widely by subspecies due to differences in habitat loss, reproduction rates, and conservation measures.
Key Takeaways
- Silverback gorillas lead troops of 5-30 individuals, with females and offspring forming the core
- Adult gorillas consume 18-25 kg of vegetation per day, mostly leaves and stems
- Western lowland gorillas inhabit dense rainforests of Central Africa from sea level to 1,300 m altitude
- Adult male silverback Western lowland gorillas typically weigh between 140-250 kg, with exceptional individuals reaching up to 270 kg
- Gestation period for gorillas is 8.5 months (257 days)
Gorilla populations continue to face pressure, making conservation efforts more crucial than ever.
Related reading
02 · Category
Diet and Feeding Habits28 stats
01
Adult gorillas consume 18-25 kg of vegetation per day, mostly leaves and stems
02
Western lowland gorillas eat over 200 plant species, favoring fruits like Aframomum when available
03
Mountain gorillas derive 85% diet from herbaceous foliage, eating 26 kg daily
04
Gorillas selectively feed on high-protein leaves, processing via hindgut fermentation
05
Fruit comprises 15-25% of lowland gorilla diet, peaking in dry season
06
Gorillas consume bark, pith, and flowers opportunistically, up to 10% of intake
07
Daily sodium needs met by licking soil at geophagy sites, 10-20 times/month
08
Insects make up <1% of diet but provide protein; ants/termites eaten by probing
09
Gorillas prefer plants with low fiber (<25% dry matter) for efficient digestion
10
Feeding bouts last 1-3 hours, interspersed with rumination-like processing
11
Mountain gorillas strip Galium leaves at rates of 1 kg/min during peak feeding
12
Western gorillas track fruit phenology, traveling farther for Dialium fruits
13
Gorillas avoid toxic plants with alkaloids, detecting via taste/smell
14
Dry season diet shifts to 90% leaves/pith, reducing fruit to <5%
15
Gorillas process cellulose with gut microbes producing short-chain fatty acids
16
Favorite foods include wild celery (Apium spp.) for hydration and minerals
17
Gorillas fell small trees (up to 10 cm dbh) to access foliage
18
Energy intake ~15,000-20,000 kJ/day from folivorous diet
19
Gorillas drink water rarely, getting moisture from vegetation >90%
20
Seasonal fallback foods: bark of Scorodophloeus zenkeri in low fruit periods
21
Gorillas eat fungi and decaying wood for micronutrients occasionally
22
Digestive transit time 30-50 hours, allowing fermentation of 50% fiber
23
Silverbacks eat first in hierarchy, influencing group nutrition
24
Gorillas use leaves as sponges to drink from tree holes, observed in captivity/wild
25
Diet diversity highest in frugivorous western gorillas: 120+ species/year
26
Mountain gorillas forage in bamboo forests seasonally, eating 20% shoots
27
Gorillas selectively browse thistle (Carduus spp.) for tender growth
28
Female gorillas with infants forage in safer, lower-risk patches
Interpretation
Diet and Feeding Habits Interpretation
Gorillas are the ultimate connoisseurs of the salad bar, meticulously curating a high-fiber, low-toxin menu across hundreds of plant species, all while strategically traveling for seasonal fruit, licking dirt for salt, and even felling small trees to get the good leaves, proving that a serious vegetarian diet requires both brute strength and gourmet discernment.
03 · Category
Habitat and Distribution25 stats
01
Western lowland gorillas inhabit dense rainforests of Central Africa from sea level to 1,300 m altitude
02
Mountain gorillas are restricted to high-altitude forests between 2,200-4,300 m in Rwanda, Uganda, and DRC
03
Eastern lowland gorillas occupy lowland forests up to 3,000 sq km in DRC's Kahuzi-Biega National Park
04
Cross River gorillas live in fragmented forests on Cameroon-Nigeria border, total range <800 sq km
05
Grauer's gorillas have a range reduced by 77% since 1994 due to mining and war, now ~7,000 sq km
06
Western gorillas prefer secondary forests with dense undergrowth for nesting
07
Gorillas migrate seasonally in some areas, moving up to 10-15 km for fruit availability
08
The Virunga Volcanoes host ~1,000 mountain gorillas across 5 national parks
09
Bwindi Impenetrable Forest in Uganda shelters ~350 mountain gorillas in 331 sq km
10
Gorillas share habitat with elephants and okapis in Congo Basin, influencing forest dynamics
11
Cross River gorilla populations number ~250-300 across 11 fragmented sites
12
Lowland gorillas nest on the ground nightly, using leaves from specific tree species
13
The total gorilla range spans 1.8 million sq km, but only 20% is protected
14
Gorillas in Lopé National Park, Gabon, use swamp forests during wet seasons
15
Mountain gorilla habitat lost 25% since 1990s due to agriculture and settlements
16
Western lowland gorillas range across 6 countries: Cameroon, CAR, DRC, Eq. Guinea, Gabon, Nigeria
17
Gorillas avoid human-modified landscapes, preferring primary forest with >70% canopy cover
18
Odzala-Kokoua National Park in Republic of Congo hosts largest western lowland gorilla population
19
Gorillas in Salonga National Park, DRC, inhabit peat swamp forests unique to the region
20
Bili-Uéré reserve has gorilla populations adapted to drier savanna-forest mosaics
21
Gorillas' elevational range in Ituri Forest spans 400-1,500 m
22
Nouabalé-Ndoki National Park, Congo, protects swamp and terra firme forests for gorillas
23
Gorillas use mineral licks (mazuku) in lowland forests for sodium intake
24
Dzanga-Sangha reserve in CAR has gorilla densities up to 4/km² in optimal habitats
25
Gorillas in Kahuzi-Biega NP lost 50% habitat to coltan mining since 2000
Interpretation
Habitat and Distribution Interpretation
It seems gorillas have mastered the art of real estate, but with their prime habitats being variously snatched, squeezed, or shattered by humans, they’re now holding a series of increasingly precarious house parties across a continent where the eviction notices are written in deforestation, war, and mining permits.
More related reading
04 · Category
Physical Characteristics30 stats
01
Adult male silverback Western lowland gorillas typically weigh between 140-250 kg, with exceptional individuals reaching up to 270 kg
02
Adult female Western lowland gorillas weigh 70-100 kg on average, significantly lighter than males due to sexual dimorphism
03
Mountain gorillas have an average body length of 165-175 cm for males excluding the tail
04
Eastern lowland gorillas possess canine teeth that can grow up to 5 cm long in adult males
05
Gorillas have a sagittal crest on the skull of adult males, which anchors powerful jaw muscles for chewing tough vegetation
06
The arm span of an adult male gorilla can reach up to 2.6 meters, nearly twice their body height
07
Infant gorillas weigh about 1.4-2 kg at birth, similar to human newborns despite larger adult size
08
Gorillas have fingerprints unique to each individual, just like humans, used for identification in research
09
The chest circumference of a silverback gorilla can measure up to 1.75 meters, showcasing immense torso musculature
10
Female gorillas reach sexual maturity at 10-12 years, males at 15-20 years due to dominance hierarchies
11
Cross River gorillas, the rarest subspecies, have shorter hair and lighter pelage compared to other Western gorillas
12
Gorillas' opposable thumbs allow precise manipulation of objects, with grip strength up to 6 times that of humans
13
Adult male gorillas have prominent sagittal crests rising up to 3-5 cm high on the skull
14
The skin on a gorilla's face is typically black or dark gray, turning lighter with age in some individuals
15
Gorillas have 32 teeth, including large canines in males for display and combat
16
The brain size of gorillas averages 450-500 cubic centimeters, about one-third that of humans
17
Gorillas walk with a quadrupedal knuckle-walking gait, with forelimbs 15-20% longer than hindlimbs
18
Hair color in lowland gorillas is black, while mountain gorillas have longer, thicker fur adapted to cold
19
Adult gorillas can consume up to 30 kg of vegetation daily, supported by a large cecum for fermentation
20
The nostril shape in gorillas is parallel and triangular, differing from chimpanzees' outward-facing nostrils
21
Silverback gorillas develop white hair on their backs around 12-15 years, signaling maturity
22
Gorillas have a prominent brow ridge protruding up to 2.5 cm over the eyes
23
The hand of a gorilla has a palm length of about 12-15 cm, with shorter fingers than humans
24
Gorillas' canines erupt at around 10 years in males, growing continuously throughout life
25
The rib cage of gorillas is barrel-shaped, providing space for a large digestive tract
26
Adult gorillas have an average height of 1.65-1.75 m when standing upright
27
Gorillas possess ischial callosities like other Old World monkeys, but less prominent
28
The tongue of a gorilla is pink and can extend up to 10 cm for grooming
29
Gorillas have a body temperature of 38.5°C, similar to humans
30
The foot of a gorilla measures 28-30 cm long, adapted for both walking and climbing
Interpretation
Physical Characteristics Interpretation
In the formidable architecture of a silverback gorilla—from its crest-anchored jaws and barrel chest to its unique fingerprints—evolution has crafted a gentle vegetarian giant whose sheer physical majesty, from a 2.6-meter wingspan to teeth built for display, belies a complex social creature that begins life no larger than a human baby.
05 · Category
Reproduction and Conservation Status27 stats
01
Gestation period for gorillas is 8.5 months (257 days)
02
Female gorillas give birth to single offspring every 4-6 years after maturity
03
Silverbacks mate with multiple females; infanticide occurs if new male takes over
04
Wild gorilla lifespan averages 35-40 years, up to 50 in captivity
05
Global wild gorilla population estimated at 316,000-380,000 as of 2018
06
Western lowland gorillas classified as Critically Endangered, declined 60% since 1983
07
Mountain gorillas number ~1,063 (2021), up from 680 in 2008 due to conservation
08
Ebola killed 90% of gorillas in some central African populations 1994-2004
09
Cross River gorillas: <300 individuals, Endangered, fragmented into 15 groups
10
Poaching for bushmeat and trophies threatens 20% annual gorilla mortality in some areas
11
Grauer's (Eastern lowland) gorillas: ~6,800 left, decline 50% since 1994
12
Habitat loss from agriculture/palm oil affects 70% of gorilla range
13
Inter-birth interval 3.9 years for mountain gorillas post-infanticide prevention
14
Captive breeding success >70% in AZA zoos, but low genetic diversity
15
Juvenile mortality 40% in first year due to disease/infanticide
16
Tourism generates $17M/year for Rwanda/Uganda gorilla conservation
17
90% of mountain gorilla population in protected areas with armed guards
18
Genetic diversity low in Cross River gorillas (heterozygosity 0.68), inbreeding risk
19
Annual population growth 2.3-2.6% for Virunga mountain gorillas since 2005
20
Veterinary interventions saved 50+ mountain gorillas from snare injuries 2000-2020
21
Bushmeat trade kills ~3,000 great apes/year, including gorillas
22
Community conservation benefits 100,000 people near gorilla habitats
23
Climate change predicted to reduce gorilla habitat by 94% by 2050 in some models
24
Reintroduction programs released 10+ lowland gorillas successfully in Gabon
25
Twinning rare in gorillas (<1% births), usually one survives
26
Anti-poaching patrols reduced gorilla killings by 66% in Salonga NP
27
Female fertility peaks 20-25 years, declines after 35
Interpretation
Reproduction and Conservation Status Interpretation
Their existence is a fragile, slow-motion ballet of cautious births and tragic losses, yet against a closing curtain of poaching and habitat loss, their stubborn survival is being fiercely, and sometimes effectively, choreographed by human hands.
Reference
Cite This Report
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APA
Christopher Morgan. (2026, February 13). Gorilla Statistics. Gitnux. https://gitnux.org/gorilla-statistics
MLA
Christopher Morgan. "Gorilla Statistics." Gitnux, 13 Feb 2026, https://gitnux.org/gorilla-statistics.
Chicago
Christopher Morgan. 2026. "Gorilla Statistics." Gitnux. https://gitnux.org/gorilla-statistics.
Sources & references
86 datasets cited across this report · attribution is report-level