Found: the giant lion-eating chimps of the magic forest
James Randerson, science correspondent
Saturday July 14, 2007
Deep in the Congolese jungle is a band of apes that, according to local legend, kill lions, catch fish and even howl at the moon. Local hunters speak of massive creatures that seem to be some sort of hybrid between a chimp and a gorilla.
Their location at the centre of one of the bloodiest conflicts on the planet, the civil war in the Democratic Republic of Congo, has meant that the mystery apes have been little studied by western scientists. Reaching the region means negotiating the shifting fortunes of warring rebel factions, and the heart of the animals' range is deep in impenetrable forest.
But despite the difficulties, a handful of scientists have succeeded in studying the animals. Early speculation that the apes may be some yeti-like new species or a chimp/gorilla hybrid proved unfounded, but the truth has turned out to be in many ways even more fascinating. They are actually a population of super-sized chimps with a unique culture - and it seems, a taste for big cat flesh.
The most detailed and recent data comes from Cleve Hicks, at the University of Amsterdam, who has spent 18 months in the field watching the Bili apes - named after a local town - since 2004. His team's most striking find came after one of his trackers heard chimps calling for several days from the same spot.
When he investigated he came across a chimp feasting on the carcass of a leopard. Mr Hicks cannot be sure the animal was killed by the chimp, but the find lends credence to the apes' lion-eating reputation.
"What we have found is this completely new chimpanzee culture," said Mr Hicks. Previously, researchers had only managed to snatch glimpses of the animals or take photos of them using camera traps. But Mr Hicks used local knowledge to get closer to them and photograph them.
"We were told of this sort of fabled land out west by one of our trackers who goes out there to fish," said Mr Hicks whose project is supported by the Wasmoeth Wildlife Foundation. "I call it the magic forest. It is a very special place."
Getting there means a gruelling 40km (25-mile) trek through the jungle, from the nearest road, not to mention navigating croc-infested rivers. But when he arrived he found apes without their normal fear of humans. Chimps near the road flee immediately at the sight of people because they know the consequences of a hunter's rifle, but these animals were happy to approach him. "The further away from the road the more fearless the chimps got," he added.
Mr Hicks reports that he found a unique chimp culture. For example, unlike their cousins in other parts of Africa the chimps regularly bed down for the night in nests on the ground. Around a fifth of the nests he found were there rather than in the trees.
"How can they get away with sleeping on the ground when there are lions, leopards, golden cats around as well as other dangerous animals like elephants and buffalo?" said Mr Hicks.
"I don't like to paint them as being more aggressive, but maybe they prey on some of these predators and the predators kind of leave them alone." He is keen to point out though that they don't howl at the moon.
"The ground nests were very big and there was obviously something very unusual going on there. They are not unknown elsewhere but very unusual," said Colin Groves, an expert on primate morphology at the Australian National University in Canberra who has observed the nests in the field.
Prof Groves believes that the Bili apes should prompt a radical rethink of the family tree of chimp sub-species. He has proposed that primatologists should now recognise five different sub-divisions instead of the current four.
Mr Hicks said the animals also have what he calls a "smashing culture" - a blunt but effective way of solving problems. He has found hundreds of snails and hard-shelled fruits smashed for food, seen chimps carrying termite mounds to rocks to break them open and also found a turtle that was almost certainly smashed apart by chimps.
Like chimp populations in other parts of Africa, the Bili chimps use sticks to fish for ants, but here the tools are up to 2.5 metres long.
The most exciting thing about this population of chimps though is that it is much bigger than anyone realised and may be one of the largest remaining continuous populations of the species left in Africa. Mr Hicks and his colleague Jeroen Swinkels surveyed an area of 7,000 square kilometres and found chimps everywhere. Their unique culture was uniform throughout.
However, the future for the Bili apes is far from secure. "Things are not promising," said Karl Ammann, an independent wildlife photographer who began investigating the apes 1996. "The absence of a strong central government has resulted in most of the region becoming more independent and lawless. In conservation terms this is a disaster."
In Search of Congo's Bili Ape
|Listen to part one||Listen to part two|
|Listen to part three||Listen to part four|
March 26 - 29, 2001 -- Listen to Morning Edition, March 26, 2001, for the latest National Geographic Radio Expeditions based on NPR’s Alex Chadwick's visit to Central Congo and the search for the Bili ape.
Researchers have long wondered about a large primate skull found a century ago in the northern Congo. Gorillas have never been reported in this region. But there are stories of very large apes -- and recent evidence suggests that something unknown may be there.
Intrigued by the possible existence of a new species of ape -- news that would rock the world of science -- some of the most renowned ape researchers in the world agreed to undertake an expedition to the Bili forest.
The area falls within the highly unstable Democratic republic of Congo, the former Zaire. Two rebel armies are fighting the central government in Kinshasa, and only a week before the expedition was scheduled to begin in January, Congo leader Laurent Kabila was assassinated. The Bili forest research site is hundreds of miles behind rebel lines; there is little civil authority; roads and communications are poor; there is no medical care. No scientists are known to have explored the area.
Day One - Listen as Radio Expeditions begins the search for the Bili Ape at a dirt airstrip in Arua, Uganda, where a small plane is refueling before flying on to the Congo. On board are two scientists -- Dr. Richard Wrangham of Harvard University and the Leakey Foundation, and Dr. Christophe Boesch of the Max Planck Institute for Evolutionary Anthropology in Leipzig. Wrangham and Boesch explain both their interest in and skepticism about the puzzling reports from Bili. The two scientists are skilled explorers with many years experience studying and following chimpanzees in the wild. They will need those skills in the days ahead, when they will camp in the forest with the Radio Expeditions team, trying to locate the elusive Bili Ape.
Day Two -- On a rutted road through the Congo forest, Radio Expeditions stops with the researchers to ask local villagers about the Bili apes. They say they know about a large ape, but pictures of gorillas don’t look familiar to them. It's a clue that perhaps the animal we’re looking for is either a large chimpanzee or possibly a new species. Listen as NPR's Alex Chadwick talks to expedition leader Karl Amman about some of the evidence that’s lured the biologists here -- including a plaster cast made near here a few weeks ago of a very large ape footprint. These are the forests of old Africa and there are things in them that are still unknown.
Day Three -- Listen as Alex follows two other scientists into the forest -- Esteban Sarmiento of the American Museum of Natural History and George Schaller of the Wildlife Conservation Society. In a day of exploring, we find a nest that may suggest the presence of gorillas, but other evidence that leans toward chimps. We also find lion tracks, ape feeding sites, and a forest of sights and sounds that are thrilling even without a mysterious ape.
Day Four -- Listen as Alex joins Christophe Boesch on an early morning trek to a distant forest site to try to find chimps. Boesch explains his technique for locating the animals and the very real crisis that confronts apes in the wild everywhere: Their homeland is being turned into farm tracts and they are being hunted for food. Ape numbers are in sharp decline, and scientists are trying to find new populations that can be protected.
Richard Wrangham introduces us to an investigative technique that is -- challenging. We wash ape feces to learn what the animals eat. Wrangham is able to conclude that the Bili ape is not a gorilla, but rather a chimp. Karl Amman plans to keep trackers in the forest to continue looking for the elusive animals that he still believes may be a new chimp. But the other scientists agree with Wrangham that the Bili ape is in all likelihood a chimpanzee. Says Christophe Boesch, that is enough. For us, the chimp is still a mystery.