Eastern Gorilla
The largest Gorilla species
The gorilla genus has two species: the Eastern Gorilla and the Western Gorilla.
The scientific name is Gorilla beringei.
It’s split into two subspecies:
- Mountain gorilla (Gorilla beringei beringei)
- The lowland gorilla, also called the Grauer’s gorilla (Gorilla beringei graueri)
Weight and Size/Height.
The Grauer’s gorilla is the largest and tallest gorilla subspecies. A silverback is an adult male gorilla. Adult males are heavier than females. When standing, they are also taller.
Height
The Grauer’s gorilla is about 170 centimeters tall. Some males can reach over 175 centimeters. Mountain gorillas have an average height of 170 centimeters.
Weight
The size of female Grauer’s gorillas is less than that of the males. An adult male Grauer’s gorilla weighs between 160 and 180 kilograms. On rare occasions, a silverback gorilla can weigh more than 200 kilograms. An eastern lowland silverback in captivity weighed 860 pounds.
An adult male mountain gorilla weighs, on average, 155 kilograms. Adult female gorillas are usually between 70 and 110 kilograms.
Where do the eastern gorillas live?
Gorilla Habitat
All gorillas are native to Africa since they evolved 7 million years ago to become primates. This species inhabits East and Central African rainforests.
Rwanda, Uganda, and eastern Congo have mountains covered in lush Afromontane forests. These areas are perfect homes for mountain gorillas. Bamboo and montane rain forests are great habitats for these apes. Mountain gorilla habitats cover altitudes of 1,400 to 3,800 meters above sea level.
You can see mountain gorillas in two places in Uganda: Bwindi Forest and Mgahinga National Park. The other mountain gorillas live in the Virunga Volcanoes area. This region covers all three countries mentioned above.
Gorilla beringei graueri, or the lowland gorilla, lives in lowland tropical rainforests. These forests extend into Afromontane areas, including bamboo forests and swamps. This type of habitat is in the Albertine Rift Valley. The Albertine region is east of the Democratic Republic of Congo (DRC).
Grauer’s gorillas occupy areas ranging from 600 to 2,900 meters above sea level. Protected areas such as Kahuzi-Biega National Park in the DRC struggle to protect gorillas due to ongoing insecurity.
How long does an eastern gorilla live?
Great apes in the wild often live to about 40 years. Scientists do not know the exact oldest age of gorillas.
No mountain gorillas live in zoos. Many attempts to keep them have failed. Only some lowland gorillas live in a few zoos worldwide.
Gorilla Diet
Gorillas eat plants. They also eat insects and some soil for extra nutrients. Common foods are shoots, leaves, stems, and fruits.
Male gorillas of the Graueri group eat about 30 kilograms of food each day. Adult females eat about 18 kilograms.
How many Eastern gorillas remain in the world?
Only the mountain gorilla has a precise count. Teams count them every 5 to 10 years in Uganda, Rwanda, and the DRC. The counts are from the Virunga and Bwindi forests.
Sarambwe Reserve and Bwindi Forest together have about 459 mountain gorillas.
The other area is the Virunga Massif. It covers three countries, including Mgahinga Gorilla Park in Uganda. Virunga National Park in the DRC, and Volcanoes National Park in Rwanda. The Virunga group has about 604 mountain gorillas.
About 1,063 mountain gorillas live in Uganda, Rwanda, and the Democratic Republic of Congo.
Eastern Lowland gorilla Population
The Lowland gorilla numbered about 16,900 in 1994. Human settlement and farming cut their numbers by roughly 77%. This loss pushed them close to extinction.
In 2015, night nest counts and simple models put Grauer’s gorillas at about 3,800. The IUCN notes their numbers fell by about 5% per year. A 5% yearly loss is about 190 fewer gorillas each year, so beringei graueri total may now be near 2,000.
There are fewer than 5,000 eastern gorilla individuals living in the rain forests of East and Central Africa.
Book a Uganda safari to learn more about gorillas.