- CLASS: Mammalia (Mammals)
- ORDER: Primates
- FAMILY: Hominidae
- GENUS: Gorilla
- SPECIES: gorilla (western gorilla), beringei (eastern gorilla)
- SUBSPECIES: Gorilla gorilla gorilla (western lowland gorilla), Gorilla beringei beringei (mountain gorilla), Gorilla beringei graueri (Grauer's gorilla), Gorilla gorilla diehli (Cross River gorilla)
Gentle giants. Ever since King Kong first gave Fay Wray that unexpected lift to the top of the Empire State Building in 1933, Hollywood has gone ape depicting the gorilla as perfect monster material. They seem to be forever typecast as the heavy. But the truth is, they’re peaceful, family oriented, plant-eating primates that live in complex social groups. They are the largest of all primates—the group of animals that includes monkeys, lemurs, orangutans, chimpanzees, and humans.
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 gorillas can use the backs of their fingers like extra feet when they walk. This is called the knuckle walk.
Like all great apes (except humans), gorillas require rainforests to make their living, and the forest depends upon them, too. The gorilla’s fibrous scat acts as rich fertilizer for the forest, and seedlings sprout from it rapidly, making gorillas important forest regenerators.
HABITAT AND DIET
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! And gorillas love to eat—it’s their favorite activity! An adult male eats up to 40 pounds (18 kilograms) of food each day. A gorilla’s large stomach can hold the bulky food it eats. Strong jaws help the gorilla chew tough stems.
Gorilla food includes leaves, stems, fruits, seeds, roots, ants, and termites. Unlike chimpanzees, gorillas don’t use tools to get those termites; instead, they just smash the termite mound to get the tasty insects living inside! At the San Diego Zoo and San Diego Zoo Safari Park, our gorillas are fed a variety of produce and browse material six times a day, as well as special treats like Cheerios and Wheat Chex cereals. This food is scattered all about the exhibit, giving the gorillas plenty of opportunities to hunt for their meals.
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 travels for food each day, when they stop to eat or rest, and where they spend the night.
A gorilla troop doesn’t stay in the same place for more than a day. After all, the troop doesn’t want to deplete its food source! Each morning the silverback leads 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 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.
Gorillas are generally peaceful creatures, but sometimes a younger male from another troop challenges the silverback. To scare unwanted gorillas away, he beats his chest with cupped hands to make a loud noise, screams, bares his teeth, and then charges forward. Sometimes he breaks off branches and shakes them at the intruder. It is an awesome display!
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. The tiny infants only weigh a few pounds at birth, and the mother is generally over 200 pounds (91 kilograms), so the births are quick and easy. A mother carries her baby against her chest for the first several months until the little one can hang on to Mom’s back, which frees up her hands to walk and carry food items.
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 youngster is its mother's back as she travels through 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 have no natural enemies or predators, yet these peaceful creatures are at critical risk because of humans. People hunt gorillas for food called bushmeat, and logging and mining companies destroy gorilla habitat. The recent armed conflict in eastern Democratic Republic of Congo has caused refugees to pour into previous gorilla habitat. Disease epidemics such as the Ebola virus have recently decimated gorilla populations that were previously considered secure within their natural habitat.
The past 15 years have seen a dramatic decline in gorilla population size, with almost half of the entire eastern gorilla population suspected to have been wiped out. Illegal hunting has become a lucrative activity in the region. While hunters often lay snares targeting other mammals, sadly, many gorillas die or lose limbs after being accidentally ensnared. An illegal pet trade is also on the rise. Behind each infant gorilla caught by poachers, several family members are often killed.
In 2000, San Diego Zoo Wildlife Alliance established a long-term field program in Cameroon, which is now part of our Central Africa Program, focusing on the behavior and habitat use of gorillas and other primates in the mountainous southwestern Cameroon rainforest. It isn’t clear whether gorillas in the area’s Ebo Forest are western lowland gorillas Gorilla gorilla gorilla or Cross River gorillas Gorilla gorilla diehli—or something else. In 2005, we received permission to establish permanent study sites inside the Ebo Forest, where surveys gathering ecological and behavioral data for various wildlife, including gorillas, are collected daily. In 2012, the Central Africa Program established Clubs des Amis des Gorilles (Gorilla Guardian Clubs) in the villages closest to the gorillas to promote community-led conservation initiatives and pride in the unique Ebo gorillas.
The critical conservation status of gorillas underscores the urgency for gorilla conservation science. In collaboration with wildlife managers and conservation scientists in countries where gorilla populations survive, San Diego Zoo Wildlife Alliance is involved in the training of range-country conservation scientists in the application of genetic tools and field methods in assessing and monitoring surviving gorilla populations. Performing the first genetic studies on populations of mountain gorillas, it was discovered that regionally, these gorillas are genetically distinct.
Genetic differences were also found within western lowland gorilla populations, which had been considered a single subspecies. By gathering and analyzing fecal samples from gorillas, conservation scientists from San Diego Zoo Wildlife Alliance and wildlife authorities and conservationists in Uganda, Rwanda, Democratic Republic of the Congo, and Cameroon can shed light on the genetic variation across regions.
Africa may seem far away, but there are some things 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 encourages logging companies in Africa to follow wildlife laws that help protect gorillas and other African wildlife.
Did you know that cellphones have a connection to the well-being of gorillas and other wildlife in central Africa? Here's the 411: cellphones contain a rare ore called coltan (short for columbite-tantalite). This metal is found in central Africa, and increased mining operations to get the coltan means habitat loss and increased hunting pressure on gorillas and other wildlife. Surprisingly, wildlife reserves suffer most from mining. With the increased popularity of cellphones, thousands of illegal miners have invaded the protected parks. Needing food, they have hunted gorillas and elephants to near extinction in these areas.
San Diego Zoo Wildlife Alliance, along with Eco-Cell, a cellular phone recycling company, has a cellphone-recycling program at both the San Diego Zoo and the San Diego Zoo Safari Park to encourage visitors to recycle. Our cellphone recycling program helps to keep those obsolete cellphones, chargers, and old batteries out of landfills and to reduce a little of the coltan demand at the same time. We have cellphone collection boxes at our two facilities, so it's really easy to simply drop off those old phones and accessories, working or not. There is no recycling fee to drop off your phone. All cellphones and accessories collected are reused or properly recycled. Every little bit helps!
By supporting San Diego Zoo Wildlife Alliance, you are our ally in saving and protecting wildlife around the globe.