Habits and Behavior of Eastern Mountain Gorillas

behaviourUntil recently it was considered that there was only one species of gorilla (Gorilla gorilla), divided into three subspecies that live in different parts of Africa, the Western Lowland Gorilla (Gorilla gorilla gorilla), the Eastern Lowland Gorilla (Gorilla gorilla graueri) and the Mountain Gorilla (Gorilla gorilla beringei). However, recent DNA evidence has led to the recognition of the eastern and western populations as separate full species classified as Gorilla beringei and Gorilla gorilla respectively. The two mountain populations, one in the Virunga Volcanoes area on the border between the Democratic Republic of Congo and Rwanda and the other in the Bwindi National Park in Uganda, belong to the Eastern group which changes their classification to Gorilla beringei beringei.

After chimpanzees, gorillas are our closest relatives and share about 97.7% of our DNA. Mountain gorillas are the largest living primates, an adult male weighing up to 180 kilograms (400 pounds), with an arm span of about two metres (seven feet).They have longer, thicker fur than Lowland gorillas and a slightly different nose shape among other skeletal differences.

behaviour_2Mountain Gorillas are family creatures and live in groups of five to more than thirty-five members. A silverback, the dominant polygamous male in the group, is the leader. The groups include the silverback, several females and offspring. Females are reproductively mature at about 7 to 8 years, but do not normally breed until 10-11 years. Females will leave their birth group before breeding and join another group. Males normally do not start breeding until 15-20 years. Gorillas do not have a specific breeding season and females normally give birth to only one offspring at a time.

Over a 40-year life span a female will normally bear 2-6 offspring. The females are nurturing mothers, who feed and groom their babies. Gorillas do not mind sharing activities, so it is not uncommon to see a silverback playing with the young or grooming them. All young gorillas are incredibly active and often pester the adults. Infants are normally weaned at about the age of three years.

behaviour_3Mountain Gorillas are principally vegetarians, but occasionally eat small invertebrates. Naturally, mountain gorillas require large quantities of food due to their massive size. Surprisingly, they do not need water because they obtain enough from the plants they eat. Over 3/4 of the mountain gorillas diet is shoots, stems, and leaves. Gorillas spend about a third of their day feeding, a third traveling, and the remainder resting. They make nests to sleep and rest in trees, on steep slopes, or on the ground.

Gorillas are usually very gentle creatures. Their only effective predators are humans. They are often thought to be "slow" or "dumb" because of their sluggishness, but in fact they are intelligent and capable of learning sign language. Gorillas are peaceful creatures and will only attack to defend their group.


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