Mammals: Gorilla

Range: Africa, mainly along the equator Habitat: Gorilla gorilla is found in lowland tropical rain forests; Gorilla berengei live higher in the rain forests, mountain slopes, and bamboo forests.

Gentle giants

Gorillas have always fascinated zoo visitors. They are the largest of all primates—the group of animals that includes monkeys, lemurs, orangutans, chimpanzees, and humans. Gorillas are peaceful, family-oriented, plant-eating animals.

Many people like to compare gorillas with humans, but there are several differences. Although they are able to stand upright, gorillas prefer to walk using their hands as well as their legs. Their arms are much longer than their legs, and they can use the backs of their fingers like extra feet when they walk. This is called the knuckle walk.

Troop leader

A group of gorillas living together is called a “troop.” There can be 5 to 30 gorillas in one troop, led by a strong, experienced male known as a "silverback." His job is a big one. He is responsible for the safety and well being of the members of his troop. The silverback makes all the decisions, such as where the troop will travel for food each day, when they will stop to eat or rest, and where they will spend the night.

Gorillas are generally peaceful creatures, but sometimes a younger male from another troop will challenge the silverback. To scare unwanted gorillas away, he will beat his chest with cupped hands to make a loud noise, scream, bare his teeth, then charge forward. Sometimes he will break off branches and shake them at the intruder.

Breakfast in bed

Can you imagine waking up each morning surrounded by food? Almost everything a gorilla eats is plant material, so life in the forest is like living in a huge restaurant! Gorilla food includes leaves, stems, fruits, seeds, and roots. And gorillas love to eat—it’s their favorite activity! An adult male will eat up to 40 pounds (18 kilograms) of food each day. Gorillas’ large stomachs can hold the bulky food they eat. Strong jaws help them chew tough stems. At the San Diego Zoo and the San Diego Zoo Safari Park, the gorillas get a variety of seasonal fruits and vegetables, plus banana and ficus leaves.

A gorilla troop doesn’t stay in the same place for more than a day. After all, they don’t want to deplete their food source! Each morning the silverback will lead his troop to a new area where food is plentiful. After a morning of munching, each adult gorilla gathers leaves, twigs, and branches to make a day nest for resting while the youngsters play. After their nap, the gorillas will eat again until bedtime, when they make yet another nest, either on the ground or in a tree, for a good night’s sleep. Gorillas never use the same nest twice.

Baby business

A female gorilla is ready to have babies of her own when she is about eight years old. But first, she must leave the safety of her own troop and find another troop or a lone silverback to live with. A newborn grows quickly. At five to six months old it learns to walk, and by 18 months of age it can follow mom on foot for short distances. Still, the safest place for the younster is its mother's back as she travels thru the dense vegetation of their forest home.

Young gorillas learn by imitating what the others in the troop are doing, and by play fighting with other youngsters. Even the stern silverbacks are gentle with the little ones as they practice new skills. A young gorilla stays close to its mom, sharing her nest, until it is four to six years old. Gorillas have been known to nurse for up to three years.

Gorillas in crisis

Gorillas have no natural enemies or predators, yet these peaceful creatures are very endangered because of humans. People hunt gorillas for food called bushmeat. Logging companies destroy gorilla habitat. Africa may seem far away, but there is something you can do to help! When you buy wood or furniture, ask if the wood has been certified. This means the wood was taken in a way approved by forestry experts. Buying certified wood will encourage logging companies in Africa to follow wildlife laws that will help protect gorillas and other African animals.

Helping gorillas

Visiting the San Diego Zoo and the San Diego Zoo Safari Park supports conservation for gorillas. A key part of the effort to conserve wild gorilla populations is to better understand the genetic diversity of those wild populations. Geneticists from San Diego Zoo Global have begun working with Ugandan scientists and will conduct studies in Rwanda, Uganda, and Nigeria to build this genetic data bank and build relationships and community support in countries that can directly help gorillas and gorilla habitat.