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A silverback is an adult male gorilla, usually 12 years or older, named after the saddle of silver-grey hair that develops across his back as he matures. Silverbacks are about twice the weight of adult females, at roughly 140–200 kg in the wild, with a tall bony crest on the head and long canine teeth. The dominant silverback leads his group: he decides where it travels, feeds and sleeps, settles disputes and defends the family. Not every male becomes a group leader, and some groups have more than one silverback.
How a male becomes a silverback
Young males grow at a similar pace to females until about eight years old. They then enter the blackback stage, when they are sexually mature but not fully grown, with dark backs and growing muscle. From about 12 years, the hair on the back and hips turns silver, the body fills out, and the sagittal crest on top of the skull, which anchors powerful jaw muscles, becomes prominent. Full size and status usually follow over the next few years. See our guide to blackback vs silverback.
What a silverback does
The dominant silverback sets the daily routine, moving the group between feeding areas and choosing nest sites. He intervenes in squabbles, often with a grunt or a stare, and protects the group from rival males and other threats with displays of hooting, chest-beating and charging. Infants and juveniles are often drawn to him and play near him while he rests. Females choose to stay with a silverback who protects them and their infants well, which is the basis of his status. See our guide to gorilla social behaviour.
Do all males become leaders?
No. Many males leave their birth group as blackbacks or young silverbacks and live alone or with other males for years before attracting females to form a new group; some never succeed. Others stay in their birth group as subordinate silverbacks. Mountain gorillas often live in multi-male groups, more often than other gorillas, and a subordinate silverback may mate with some females and eventually take over when the leader weakens or dies. When a dominant silverback dies without a successor, the group may split up or join another male.
Size and strength
Standing upright, a silverback is about 1.5–1.8 metres tall, though he rarely stands; on all fours he walks on his knuckles. His arm span can exceed two metres. Gorillas are very strong for their size, but popular claims such as “ten times stronger than a human” have no scientific measurement behind them. Silverbacks can live into their 30s and occasionally 40s in the wild. See our guide to how much a silverback weighs.
Meeting a silverback on a trek
Most of your hour with a gorilla family is spent watching the silverback eat or rest, often surprisingly calm. If he stands, beats his chest or makes a short charge, stay still, crouch, look down and follow the ranger; habituated silverbacks rarely make contact. Keep at least seven metres back. The permit costs US$800, or US$600 in April, May and November. See our guide to how gorillas communicate.
Frequently asked questions
The silver saddle appears from about 12 years old.
Yes. Only adult males develop the silver saddle.
Yes. Multi-male groups are common among mountain gorillas, with one dominant leader.
Roughly 140–200 kg in the wild, about twice an adult female.
