western lowland gorillaScientific Name– Gorilla gorilla gorilla

Conservation Status– Critically endangered

Appearance

The western lowland gorilla is the smallest of the gorilla species. They have a black coat which covers their whole body except for their ears, feet and arms. The face only has hair along the brow bridge. Their skin is jet black. Mature males have silver fur along the back gaining them the name ‘silverback’. They have hands which are large in proportion to their body. Western lowland gorillas do not have tails.

When a male stands on his hind feet he may measure up to 1.8m (6ft). They weigh in the region of 140-270kg (300-600 pounds). Females are normally 1.5m (5ft) tall and weigh about half the weight of the females.

Lifespan                                                                                  

Western lowland gorillas live for between 30 and 40 years in the wild. In captivity they may live to be 60.

Diet

The western lowland gorilla is an omnivore. People regularly say they are herbivores though this is untrue as they will eat insects as part of their diet. These are normally ants and termites. They have also been seen eating rodents and small lizards but this is less common. Gorillas feed upon ripe fruits and pith when that is available majorly during the wet season. At other times of the year they will feed on herbs, leaves, nuts, berries and dry bark. Most of the fruit they consume is high in sugar as this provides large amounts of energy.

western lowland gorillaGorillas will never remove all of the food items which are in an area. This aids quick growth rates which allows them to live in a small area.

Habitat

This species natural home is Africa. The western lowland gorilla is the most widespread of all the gorilla subspecies. They can be found in Cameroon, the Central African Republic, Gabon, the Republic of Congo, Equatorial Guinea, Nigeria and the Democratic Republic of Congo.

Western lowland gorillas make their home in tropical rainforests, swamp forests, brush, secondary forests, abandoned farming areas, riverine forests, clearings and forest edges.

Reproduction

Female gorillas are able to breed once they turn 8. The males are not considered mature until they are 15. Only the alpha male in a group will mate with the females to produce young. Western lowland gorillas have a gestation period similar to humans (9 months). After this time a single infant is born on most occasions.

After the female gives birth she will cut her own umbilical cord. Her infant will have a spare covering of fur over its pinky-grey skin. The baby is born helpless and needs to be carried around by the mother in her arms.

The baby is held close to the belly of the mother for two months until it can hang on by itself. Once it has learnt how to cling on it will spend another two months on the belly. After this it will move to the back of the mother where it rides until it is three years old. Infants may be under the care of their mother for up to 5 years.

Behaviour

Western lowland gorillas maintain a home range but it is not strict. Regularly they have been seen allowing other gorillas to enter this range. The main point of this area is to follow the seasonal patterns around it to find food.

western lowland gorillaThis species is highly social. An average group has a silverback male, three females and their offspring. Young males who have left their natal group will branch out and move around on their own or in small groups. When females leave they do not move around alone. They will jump between different groups until they find one to settle in.

Each night the western lowland gorilla will construct a nest in which they can sleep. They also create one of these for their midday nap. During the morning they eat and then go in for a nap at midday. By afternoon they are out foraging again before sleeping again at nightfall.

Gorillas communicate using over 25 noises which include hoots, barks, screams, laughs and grunts.

Humans, crocodiles and leopards are the predators of western lowland gorillas. To scare these off they may use chest beating, running sideways and tearing up vegetation. These may also be used to display their dominance in the group.

To assist in peeling fruit the western lowland gorilla has opposable thumbs like humans do.

Quick facts

Gorillas are affected by the Ebola virus with 2 major outbreaks being reported in 2003 and 2004.

Western lowland gorillas are very intelligent. They make a range of tools which simplifies their foraging process. One famous gorilla, Koko managed to learn 1,000 signs.

An albino western lowland gorilla was one caught. She lived at the Barcelona Zoo and was known as Snowflake.

The male gorillas are regularly prone to cardiomyothapy.

Western lowland gorillas are the most common variety found in zoos.

Between the ages of 3 and 6 western lowland gorillas are regularly referred to as human-like.

Photo Credits:

Top        – By Jackhynes (Own work) [CC-BY-SA-3.0 (http://creativecommons.org/licenses/by-sa/3.0)], via Wikimedia Commons

Middle – Public domain

Bottom – Public domain