It is estimated that the population is less than 5,000 individuals. Researchers have been unable to conduct extensive surveys since the mid 1990s, but the population is believed to have declined by 70-80% in the last 15 years.
The range of Eastern Lowland Gorillas range is estimated at 21,600 km², a decline of 25% from surveys completed in 1959. In addition to this, population range is fragmented and separated due to increased human population density and associated activities.
Characteristics and Behaviour
Eastern Lowland Gorillas are peaceful, mainly herbivorous animals that live in groups of 5-30 individuals. Individual males can weigh up to 250kg in captivity, but in the wild they usually weigh 200kg. Females are significantly smaller, with a maximum weight of 110kg. Eastern Lowland Gorillas live in family groups consisting of a large dominant male Gorilla and females and infants. Males are known as “Silverbacks” in reference to the distinctive silver hairs on their back upon reaching maturity. Gorillas are identified by their “nose prints,” which are the patterns of wrinkles on their noses. Each gorilla has a unique nose print.
The gestation period for female gorillas is 8 ½ months. Gorilla infants are helpless at birth, learning to walk independently around 9 months. Infant gorillas are nursed for about 3 years before becoming fully independent. Female gorillas gain maturity around the age of 10 years old and have only one baby every four years, meaning that over the 25 year life span she will only give birth to an average of 3 offspring. The slow reproductive rate means that it can take many years for a population to recover from threats such as hunting and ongoing conflict.
The diet of Eastern Lowland Gorillas mainly consists of leaves, but they have also been observed consuming fruit, seeds, bamboo shoots and insects. Mostly active during the day, they make a new nest each night, with mothers sharing with infants. Watching a gorilla sitting peacefully in the forest eating and socialising is a truly magical experience.
Gorillas communicate in a variety of different ways. Vocal communication occurs between individual gorillas, and within larger groups. Adults and infants have a variety of different calls depending on the situation. “Close” calls are commonly given within the group in situations of either potential separation or potential conflict. Extra-group calls serve to alert group members of potential predation and include “barks” or are given as long-distance threat displays upon detection of another group. These can also be accompanied by chest beating, a common non vocal communication method.