Western Lowland Gorilla

At the Detroit Zoo
Half-brothers Chipua (born in 1996), Pendeka (born in 1998) and Kongo-Mbeli (born in 1998) arrived at the Detroit Zoo in 2003 and can be seen at the Great Apes of Harambee, a 4-acre habitat that is also home to chimpanzees. In the winter months, the gorillas can been seen in the habitat’s indoor viewing area.

The hair on the back of these males has either turned or is turning silver-gray with age, earning them the name “silverback”. Chip became a silverback first and for a while was the most dominant. Now, Kongo is most dominant due to his size. Since Pende has matured into a silverback, he has been less interested in the power struggle.

Visitors often ask why there are no females. Typically, gorillas in the wild live in large family units (a single silverback with several females and offspring). Some of those offspring will eventually mature into reproductive males that could challenge the status of the resident silverback. So it is estimated that, at about 6 to 10 years of age, those males are driven out or leave on their own. Since gorillas are very social animals, these juvenile males form bachelor groups temporarily. In captivity, we have to help them out in that bachelor group establishment. In the 1980s the Gorilla Species Survival Plan (SSP) had to provide companions for these male offspring and also find a way to optimize the use of limited captive space. Since then, managing a bachelor group of gorillas has been an important part of the Gorilla SSP captive management plan. What we learn by working with these three males will aid other zoos when forming additional bachelor groups.

Description
Western lowland gorillas are large, muscular primates. They have black skin and coarse hair ranging in color from brown to gray. The hair on the back of the males will turn silver-gray with age, earning them the name “silverback”. They have small ears, large nostrils, one well-defined brow and short muzzles.