Eastern Lowland Gorilla

The Eastern lowland gorillas are one of the sub-species of gorillas (fall under the Eastern gorillas) and are considered the largest of all the sub-species of gorillas which explains why you should visit this country and see an animal that is two times larger than a mature human being. The Eastern Lowland Gorillas are homed in different areas on Eastern democratic Republic of Congo but the highest population is found in Kahuzi-Beiga National Park.

The eastern lowland gorilla is also known as Grauer’s gorilla and the largest of the four gorilla subspecies of the eastern gorilla endemic to the mountainous forests of eastern Democratic Republic of the Congo. Important populations of this gorilla live in the Kahuzi Beiga and Maiko National Parks and their adjacent forests, the Tayna Gorilla Reserve, the Usala forest and on the Itombwe Massif

It is distinguished from other gorillas by its stocky body, large hands and short muzzle. Despite its size, eastern lowland gorillas subsist mainly on fruit and other herbaceous materials, just like other gorilla subspecies. Although the hair is shorter on the head and body. The male’s coat, like that of other gorillas, turns silver at the back as the animal matures. There are many more western lowland gorillas than the eastern variety; compared to over 100,000 western lowland gorillas, there were only about 5,000 eastern lowland gorillas in the wild in a 2004 report and fewer than 3,800 in a 2016 one. Outside the native range, only one female lives in captivity at the Antwerp Zoo in Belgium.

The eastern lowland gorilla makes its home in lowland tropical rainforests in the eastern DRC. In the last 50 years, its range has decreased from 8,100 square miles—about the size of the state of Massachusetts— to about 4,600 square miles today. This subspecies may now occupy only 13% of its historical range. You can visit these great apes on a Congo Gorilla Tour within Kahuzi Biega National Park, the only place where a few gorilla families have been habituated for tourism.

Physical description

Also known as Grauer’s gorilla, the eastern lowland gorilla is the largest of the gorilla subspecies. This impressive animal is identified by a stocky body, large hands and a short muzzle. Unusually, the gorilla’s thumbs are larger than the fingers. The face, ears, hands, and feet are bare, and the chest in old males lacks hair.

Compared to the other eastern gorilla subspecies, the mountain gorilla, the eastern lowland gorilla has shorter hair and teeth, and longer arms.


This subspecies consumes parts of at least 97 plant species. About 67% of their diet is fruit, 17% is leaves, seeds and stems and 3% is termites and caterpillars. the diet of eastern lowland gorillas is more diverse than the mountain gorillas’ and changes seasonally. While leaves and pith are staple parts of their diets, eastern lowland gorillas depend heavily on fruit (25 percent of their total diet), especially during the times of year when fruits are abundant. When they include insects in their diet, eastern lowland gorillas prefer ants Eastern lowland gorillas generally use a small area for a few days and then travel long distances to another area. Eastern lowland gorillas that depend more heavily on fruit must travel farther in a day to find fruiting trees and have larger home ranges because of a relative scarcity of fruit. Their home ranges vary from 2.7 to 6.5 km²


Eastern lowland gorillas are highly sociable and very peaceful, living in groups of two to over 30. A group usually consists of one silverback, several females and their offspring. Silverbacks are strong and each group has one dominant leader. These males protect their group from danger. Young silverback males will slowly begin to leave their natal group when they reach maturity, and will then attempt to attract females to form their own group.

Most primates are bonded together by the relationship between females, a pattern also seen in many human families. Once they reach maturity, both females and males usually leave the group. Females usually join another group or a lone silverback adult male, whereas males may stay together temporarily, until they attract females and establish their own groups. It is commonly believed that the structure of the gorilla group is to prevent predation.


A female will give birth to a single infant after a gestation period of about 8½ months.They breastfeed for about 3 years. The baby can crawl at around nine weeks old and can walk at about 35 weeks old. Infant gorillas normally stay with their mother for three to four years and mature at around 8 years old (females) and 12 years old (males).

Main threats of eastern lowland gorillas

Habitat loss and degradation
There are few protected areas within the eastern lowland gorillas range. Due to civil unrest, its stronghold, Kahuzi-Biega National Park, is under severe threat from poachers and encroachment, and it has been very difficult for park guards to patrol borders in this region.
People have moved into the park in order to mine coltan, an alloy used for mobile phones. This has also resulted in forests being cleared for farming.

Conflict & instability
civil conflict and political instability have left the Congolese National Parks network in a state of dereliction, hampering the effective conservation of the eastern lowland gorilla.

Hunting and trade
The trade in bush meat, which occurs over much of the eastern lowland gorillas range, may now be more of a threat than habitat loss and degradation, but the number of gorillas killed annually is unknown. The influx of people into Kahuzi-Biega National Park has also resulted in an increase in bush meat hunting.
Gorillas are also sought after as food and pets, and their body parts are used in medicine and as magical charms.

Gorillas do not eat banana fruits, but they may destroy banana trees to eat the nutritious pith. Farmers who have come in contact with gorillas in their plantations have killed the gorilla and obtained a double benefit, protecting their crop and using the meat of the gorilla to sell at the market.

Other reasons for killing gorillas are: instances of killing gorillas as revenge for confiscation of illegal charcoal or other law enforcement, or the destruction of gorilla habitat as a result of logging, charcoal, agricultural expansion or mining.

Widespread artisanal mining activities often controlled by rebel militias are the major source of hunting pressure for gorillas and other wildlife. Eastern lowland gorilla is also experiencing a range reduction due to an expanding human population.


Illegal logging may occur from companies with no rights to the land or by legal landholders. Over-harvesting is an illegal practice often conducted by legal concession holder and encourages deforestation and illegal resources exportation. The areas logged are prime gorilla habitat and is considered an international concern.