Habitat loss may be to blame for an apparent spate of violent attacks by chimpanzees on humans in the war-torn eastern region of the Democratic Republic of the Congo (DRC).
According to officials at Virunga National Park, located on the border between the DRC, Uganda and Rwanda, at least one person – a child – has been killed in recent months, in a chimpanzee attack just south of the park in the area around the city of Goma.
A woman attempted to scare the chimp away to protect the child, says Alison Mollon of the Frankfurt Zoological Society (FZS) in Germany, which works in partnership with the park. Unfortunately, the chimp reacted aggressively. “It generally seems that where people react aggressively, the result is aggressive behaviour in return,” she says.
Mistrust of chimpanzees has been heightened by local media reports, which suggest that as many as 10 people have been killed and 17 injured by chimps, in acts that were reported as “revenge attacks” for people encroaching on their territory.
Such reports highlight the urgent need to defuse the situation – both by educating locals in behaviours that will minimise the chances of violent confrontations, and by habituating chimps to humans. But efforts are being thwarted by the armed conflict between M23 rebels and the DRC government, which began in April.
“As soon as we can return, we will distribute information flyers in Swahili and French,” Mollon says. But putting out clear, useful information becomes more difficult once rumours of violence have spread.
Mistrust and antagonism
Klaus Zuberbuhler, a psychologist at the University of St Andrews in Fife, UK, and scientific director of the Budongo Conservation Field Station in Uganda, says restricting the chimps’ habitat can certainly affect their behaviour, though it is debatable whether the chimps’ aggression towards humans is a form of revenge. “It may be a more general sign of mistrust and antagonism, which is regularly seen in chimp sanctuaries and other captive facilities,” he says.
Reports of the scale and number of attacks are probably exaggerated, says Richard Wrangham of Harvard University, but he concedes that there has been an increase in tension between humans and chimps in that corner of the DRC – although only in areas where chimp habitat has been lost.
“Human-wildlife conflict is an extremely serious issue in Virunga, as it is across Africa and elsewhere,” says Emmanuel de Merode, chief warden at Virunga. There is an ongoing surge in human population in the area, he says, and wherever the park’s land is illegally used for farming, park authorities are obliged to uphold laws to protect it.
Even if the chimp attacks subside, they may well erupt again in future because of the ongoing pressure from humans. Vernon Reynolds, a biological anthropologist at the University of Oxford, and author of The Chimpanzees of Budongo Forest, says he is aware of a few past incidents around Kasowka Forest in Uganda in which chimps have attacked humans after losing much of their food supply to farming.
“There is undoubtedly a lot of exaggeration, and stories abound,” he says. “But the reality is bad enough.”