Undoubtedly the star attraction of Howletts and Port Lympne, the greatest of apes is also sadly one of the most endangered in the wild. Howletts and Port Lympne are world leaders in the captive management and breeding of this magnificent species and to date the parks have had around 130 births! Tucked away in the heart of Kent, it’s amazing to know that our parks have the world’s largest captive collection of this awe-inspiring ape – with a combined total that averages around 70 individuals.
HABITAT: There are two different species of gorilla (Eastern and Western) divided into four different subspecies that are native to the tropical and subtropical forests of Africa. The two subspecies of Western gorilla – Western Lowland and Cross River –differ significantly in number and range. Western lowland gorillas are the most abundant of all the gorilla subspecies and live in montane, primary and secondary forests as well as lowland swamps across Cameroon, the Central African Republic, Congo, Gabon, Equatorial Guinea, and Angola.
CHARACTERISTICS: While gorillas are the largest of the apes, the Western lowland gorilla is the smallest of the four subspecies. However, ‘small’ is a relative term where gorillas are concerned as males – which can grow to around 1.8m tall - can weigh 140 - 270 kg – two to four times as much as an average human male of the same height! Females are smaller and lighter, usually weighing around half of what a male does, and growing to around 1.5m tall. Mature dominant males have conspicuous light grey hair on their backs, which gives them their name of 'silverback'. The bony crest on the top of the skull is the attachment point for powerful jaw muscles, and gives their head a helmet-like appearance.
BIOLOGY: Led by the group’s silverback, gorillas move across a large range and spend around 60% of their day foraging and travelling, while the other 40% is spent resting. Wild gorillas live in troops of a single adult male and several females with their young. The silverback male keeps the peace within the group and protects them from danger. Bachelor males usually live a solitary life, but may sometimes band together with other bachelors for a while. With longer arms than legs, gorillas walk around on all fours in a semi-erect position with knuckles to the ground. They are also adept climbers, and spend a significant degree of time in the trees foraging or sleeping in purpose-built ‘nests’ made from flattened branches and large leaves.
Females reach breeding age at around 8-10 years old; while males are not mature until 11-15. Their breeding cycle is similar to humans, with a gestation period of eight and a half months, and a birth every 4-5 years. Newborns weigh around 1.8-2.2 kg and are dependent on their mothers for 3-4 years. Mothers hold their infants until they are about two months old, after which it is able to ride on her back, clinging to her fur.
CONSERVATION STATUS: All gorilla subspecies are classified as Critically Endangered though Western lowland gorillas are the most abundant of all four subspecies. Population estimates range from 100,000 - 150,000, but the true figure is very difficult to gauge. What is not in dispute is that their numbers are in drastic decline due to the bushmeat trade, deforestation and the Ebola virus. Gorillas are hunted for bushmeat and continue to be widely eaten in Central Africa. Commercial logging not only destroys gorillas' homes but also makes it easier for hunters to access the more remote areas where gorillas live. The Ebola virus is believed to be the cause of a massive decline in Central African gorilla populations during the 1990s and may have resulted in losses of up to 1/3 of the total population.
BREEDING AT THE PARKS: Part of the overwhelming success we have had with this species at our parks is down to the efforts we have made to replicate their natural conditions as much as possible – from feeding to enrichment and social structures. Feeding included regular scatter feeds that encourage our gorillas to forage through the straw, and roof feeding that requires gorillas to use their arms to brachiate. Roof feeding also ensures that all apes get their share of herbs and fruit. Once juveniles are habituated to the upper reaches of their enclosure, it provides the perfect getaway from an aggressive older animal. An extensive roof also provides ample sites from which to hang ropes, spheres, swings, play platforms and other enrichment devices to keep our gorillas stimulated and active.
The management of Howletts and Port Lympne gorillas is modelled on the social structure in the wild, with separate enclosures for a number of family groups each led by a silverback and separate 'bachelor' accommodation for other males. The breeding groups at Howletts s and Port Lympne play an important role in gorilla conservation. Not only are we successful breeders of this species but we have returned a number of captive-bred gorillas to Africa to join in on our reintroduction programmes in the Congo and Gabon. Find out what The Aspinall Foundation is doing to help prevent the extinction of this endangered species in 'Born to be Wild'