Apes on the edge: Success or failure for gorillas?

24 September 2022


On World Gorilla Day, our Head of Conservation, Dr Nikki Tagg, examines the double-edged reality faced by our closest cousins.

A gorilla reclining in the green undergrowth

Gorillas are apes on the edge – a species whose history is flecked with successes and failures. The plight of gorillas exhibits a kind of double-edged reality, with some populations rapidly surging towards the brink of being lost forever while others have become among the few major conservation success stories of our time. This indicates that the world knows that gorillas are important to save, and that saving them is possible. 

Dr Nikki Tagg

There are two species of gorilla, those living at the eastern limits of their range across sub-Saharan Africa and those living towards the west. Each species is further divided into two sub-species, giving us the eastern lowland (or Grauer’s) and the mountain gorillas in the Democratic Republic of Congo (DRC), Uganda and Rwanda, and the western lowland and Cross River gorillas in the Republic of Congo, Central African Republic, Angola, Gabon, Equatorial Guinea, Cameroon and Nigeria (Cross River gorillas live only in the latter two).

The eastern species exhibits a dichotomy in its plight. Famously, the mountain gorilla came dangerously close to extinction in the 1990s and 2000s as the Rwandan genocide and later the Congolese civil war caused environmental damage and high levels of poaching in the Virunga-Bwindi national parks, resulting in the annihilation of gorilla families and causing the population to plummet to just 240 individuals. The sub-species has since been extremely closely monitored and protected over the last 30 years, bringing mountain gorilla numbers up to a wonderful 1,000+ today. In contrast, the Grauer’s gorilla, living in greater numbers but in lands settled by rural people in the lowlands of DRC and lacking this fierce protection, have suffered a dramatic decline of 80% in the last 20 years, with their numbers now estimated to be around 6,800 and falling.

The plight of the western gorilla tells a similar two-pronged story. The Cross River gorilla sub-species, living only in the mountainous and rugged Cross River region spanning the Cameroon-Nigeria border, fell to possibly as few as 100 individuals in the 80s and 90s. The subspecies has since been studied for 20 years and conservation efforts have been set up thanks to long-term funding and strict management of Mbe and Afi protected areas.

“The plight of gorillas exhibits a kind of double-edged reality, with some populations rapidly surging towards the brink of being lost forever while others have become among the few major conservation success stories of our time.”

Though its long-term survival is far from assured, the Cross River gorilla population is now estimated to number around 300 and reproducing family groups were recently captured on remote operated camera traps, eliciting hope and optimism across the conservation world. We wish them the same success as experienced by their eastern mountain-loving relatives.

So that leaves us with the story of the western lowland gorilla, the most numerous of the gorilla sub-species, possibly in the region of 150,000 today, and also the most widespread, living across 6 West and Central Africa countries. We should be able to sit back and relax and be sure of the persistence of this abundant great ape?

Quite the opposite unfortunately.

Far from ‘safe’, the western lowland gorilla is recognised as critically endangered due to current trends indicating that it’s decline exceeds 80% over three generations and because of the increasing and unrelenting threats facing its habitat and its existence. Sharing much of its lowland range with rural people – only 14% of its 700,000km2 range is protected, which is equivalent to less than half the size of the UK – western lowland gorillas are threatened by poaching, which can lead to huge suffering among family groups and infant gorillas are often forced into the pet trade; disease, for example, Ebola has caused massive ape die-offs since the 80s, in some cases killing off 95% of a population and taking 10 years for the population to recover; and large-scale habitat degradation and destruction, particularly for oil palm cultivation and mineral extraction. Increasingly, climate change is becoming a real threat and will further complicate their protection: the region may become drier, it may experience more extreme weather in terms of rainfall and temperature, and an increased susceptibility to wildfires. All such changes directly affect animals, but also cause shifts in plant species distribution leading to lack of food for animals.

Here at Born Free, we cannot stand by as the story of the western lowland gorilla unfolds on a path towards an unhappy ending. We chose to focus our efforts on the Dja landscape in southeast Cameroon. The Dja is an important priority landscape for conservation according to the current IUCN Regional Action Plan for western lowland gorillas. Here, gorillas have declined 80% since 1995 and are now estimated to number fewer than 1,300 individuals within the UNESCO World Heritage classified core area of the Dja Faunal Reserve. Through a long-term, holistic programme of close community engagement – offering skills training for sustainable trade – as well as primary environmental education, community awareness raising, wildlife law enforcement and habitat restoration, the Born Free team has every intention to help re-write the story for western lowland gorillas of Dja and help make the changes necessary to secure this mystic animal’s future. We aspire to be part of an effort that can also be deemed a conservation success story, pulling western lowland gorillas away from the edge.

Be part of the western lowland gorilla’s success story – support our Guardians of Dja programme today.