The gorilla is a shy and, for the most part, inoffensive, leaf-eating vegetarian— a far cry from the fearsome, aggressive creature depicted in films and comic books. Only when provoked or threatened does it rise to an erect position and beat its cupped hands against its chest in an attempt to intimidate intruders of its territory.

Gorillas are the largest and most powerful of the apes. Adult males reach an average height of 1.7 m (6 ft.) and weigh from 140 to 275 kg (308 to 605 lb.). Females are about 40 to 50% smaller. Both males and females are tremendously powerful, possessing the ability to tear branches from bushes and uproot small trees. They spend their days quietly, either in a leisurely search for food, or resting in the warm sun. Gorillas are native to the equatorial regions of Africa.

The mountain gorilla is the largest of the gorilla subspecies. It inhabits a number of isolated areas on the forested mountain slopes of eastern Zaire and parts of Uganda and Rwanda. Although much of the animal's range is within national parks and reserves, these areas are encroached upon by the spread of farming and grazing lands. These disruptions may also force other animals, such as elephants and buffalo, into a reduced habitat, where competition with the gorilla for the same foods will increase. Regrettably, these animals are diminishing in numbers because of illegal hunting and encroachment by humans. The gorilla is classified as an endangered species, and the mountain gorilla subspecies is considered to be critically endangered. The greatest threat to the mountain gorilla is poaching, and the continuing civil wars in the region have increased their mortality from accidents and hunting. The wars also draw men from and interfere with the work of the patrol units, thereby reducing the controls on poachers.