The world's largest gorillas have been pushed to the brink of extinction by a surge of illegal hunting in the Democratic Republic of Congo, and are now critically endangered, officials said Sunday.
With just 5,000 Eastern gorillas (Gorilla beringei) left on Earth, the majestic species now faces the risk of disappearing completely, officials said at the International Union for Conservation of Nature's global conference in Honolulu.
Four out of six of the Earth's great apes are now critically endangered, "only one step away from going extinct," including the Eastern Gorilla, Western Gorilla, Bornean Orangutan and Sumatran Orangutan, said the IUCN in an update to its Red List, the world's most comprehensive inventory of plant and animal species.
Chimpanzees and bonobos are listed as endangered.
"Today is a sad day because the IUCN Red List shows we are wiping out some of our closest relatives," Inger Andersen, IUCN director general, told reporters.
War, hunting and loss of land to refugees in the past 20 years have led to a "devastating population decline of more than 70 percent," for the Eastern gorilla, said the IUCN's update.
One of the two subspecies of Eastern gorilla, known as Grauer's gorilla (G. b. graueri), has drastically declined since 1994 when there were 16,900 individuals, to just 3,800 in 2015.
Even though killing these apes is against the law, hunting is their greatest threat, experts said.
The second subspecies of Eastern gorilla -- the Mountain gorilla (G. b. beringei) -- has seen a small rebound in its numbers, and totals around 880 individuals.
According to John Robinson, a primatologist and chief conservation officer at the Wildlife Conservation Society, the Rwandan genocide sparked a disastrous series of events that impacted gorillas, too.
"The genocide pushed a lot of people out of Rwanda, a lot of refugees into eastern DRC, who moved into areas which were relatively unoccupied by human beings," he said.
"It was a situation that kind of unraveled," he said.
Some people hunted gorillas for bushmeat, while activities like mining and charcoal production and human settlement also infringed on gorillas' habitat.
"The people that moved into that part of DRC saw gorillas as a delicacy," Robinson said.