They are some of the most mysterious apes on the planet that according to local legend, kill lions, catch fish and even howl at the moon. But according to an 18-month study of remote human settlements deep in the Congolese jungle, chimpanzees are being subjected to a "wave of killing" by bushmeat hunters. (At right: market selling bush meat)
The scientists who carried out the study believe that the region, in the north of the Democratic Republic of the Congo (DRC), is home to at least 35,000 of the unusually large sub-species of chimpanzees. This is probably the largest population of chimps in Africa, but such is the hunger for chimp meat that the researchers believe the animals are facing a "major and urgent threat" and that northern DRC is now "witnessing the beginning of a massive ape decline."
"I was actually astonished to see the sheer quantities of bushmeat being taken out of the forest," said team member Dr Cleve Hicks, at the University of Amsterdam. "It was really shocking." He estimates that roughly 440 animals in the region are being slaughtered each year.
Because of the remote nature of the terrain and the ferocity of the DRC civil war, it was only in the last decade that the apes were studied in detail by primate researchers. Hicks documented a group of super-sized chimps with a unique culture, including a sighting of the apes feasting on a leopard carcass - although it was unclear whether they had actually killed the animal. He said that the local belief that the animals howl at the moon has never been confirmed.
To document the threat posed by bushmeat traders, Hicks and his colleagues conducted regular surveys of bushmeat markets in local towns and on roads on either side of the Uele river in northern DRC. In total they spent 1,365 days in 10 cities and towns and surveyed 13,140km of road. They recorded chimp carcasses and orphans for sale. The primatologist, Dr Jane Goodall, has estimated that for every chimp orphan that is sold as a pet, 10 others from its family group will have been killed.
In total, the team saw 44 orphan chimps and 35 carcasses, plus nine leopard skins, 10 okapi (a type of antelope) skins, parts of 14 elephants, bushmeat from two hippos, 169 monkey carcasses and 69 monkey orphans. Two of the orphan chimps had their top incisors knocked out or burned down with hot knives to prevent them from biting their handlers.
The study is published in the peer-reviewed journal African Primates.
Almost all of this trade, which the researchers describe as "larger and more widespread than anticipated, and expanding", is happening in the region south of the Uele river. Here the human population is more dense than to the north because of illegal artisanal gold mining operations. Also local taboos about eating bushmeat have begun to break down in recent years.
Hicks, who is also affiliated with the Max Planck Institute for Evolutionary Anthropology in Leipzig, Germany, said that one tribe, the Barisi, used not to harm the animals because they believed their tribe was descended from a union between a man and a female chimp. The women of two other tribes, the Azande and Babenza, previously refused to eat or cook ape meat for fear that it would result in them giving birth to babies with "big ears".
The spread of a Christian group called the "message believers" whose doctrine is based on the teaching of an American faith healer and preacher called William Branham who died in 1965 has swept away some of the old beliefs. Hicks said that followers interpret his teachings as condoning bushmeat hunting.
Hicks said that many people do not know that it is against DRC law to hunt chimpanzees and that the law is not enforced locally. Some of the people who had orphan chimps even showed the researchers documents signed by local officials that purportedly gave them permission to keep the animals.
"Once the population is fragmented [its decline] is probably going to speed up rapidly," said "Hicks. "What we are seeing probably is the beginning of that process. Its not too far gone yet too stop it ... There are very few roads so theoretically it wouldn't be that difficult to control."
Alice Macharia of the Jane Goodall Institute in Arlington, Virginia said: "The increasing level of the bushmeat trade in this region is truly alarming. In the Democratic Republic of the Congo, which has the largest population of chimpanzees in the wild, the bushmeat trade, the illegal commercial hunting of chimpanzees, remains one of the greatest threats to their survival along with loss of habitat due to deforestation. When roads are cleared to make way for mining, logging and other concessions, hunters have greater access to these endangered animals."
The Guardian, "Congolese chimpanzees face new 'wave of killing' for bushmeat", accessed September 9, 2010