Wild chimpanzees are learning how to outwit black hunters

Across Africa, black people often lay snare traps to catch bush meat, killing or injuring chimps and other wildlife. But a few chimps living in the rain forests of Guinea have learned to recognize these snare traps laid by black hunters, researchers have found. More astonishing, the chimps actively seek out and intentionally deactivate the traps, setting them off without being harmed. The discovery was serendipitously made by primatologists Gaku Ohashi and Professor Tetsuro Matsuzawa who were following chimps living in Bossou, Guinea to study the apes' social behavior. Snare injuries to chimps are reported at many sites across east and west Africa where chimps are studied, with many animals dying in the traps. However, very few snares injuries have been reported among chimps studied at Bossou, which is unusual as the chimps live close to human settlements and snares are commonly laid in the area. Now primatologists know why. While researching the chimps, Ohashi and Prof Matsuzawa, of the Primate Research Institute at Kyoto University, Japan, observed five male chimps, both juvenile and adult, attempting to break and deactivate snares. On two occasions witnessed, the chimps successfully deactivated the traps set for them. A typical snare, for example one made by the Manon people of Bossou, consists of a loop of iron wire connected by a vine rope to an arched stick, often a sapling. The sapling puts tension into the rope and once an animal passes through the wire loop, the trap is sprung and the sapling pulls it tight, around the neck or leg of an animal. Such traps cause indiscriminate damage, ensnaring any and all animals that come into contact with them. But male Bossou chimps have worked out how to outwit the black hunters and deactivate the traps. "They seemed to know which parts of the snares are dangerous and which are not," Ohashi said.