Groups of roving chimpanzees were caught red-handed stealing crops from farmers in Uganda at night, by hidden camera traps.
The pesky primates may have developed their thieving behavior as a way of co-existing with their human neighbors, whose farmland has been encroaching on the chimps' habitat, researchers say.
A team of scientists laid camera traps in the maize fields of Uganda's Kibale National Park to observe the animals' illicit activities. Over the course of three weeks, the cameras recorded a total of 14 crop raids, according to the study, published today (Oct. 22) in the journal PLOS ONE. [See Video of Chimps Stealing Food]
Chimpanzees usually hang out in groups of three, but the researchers observed parties of about eight chimps in the videos of the raids. Some females in the videos even had infants clinging to them.
The videos also revealed the chimps raiding crops at night, a risky behavior because more predators may be around. Nighttime raids have occasionally been reported during full moons, but this is the first time the animals have been known to engage in such frequent raids in the darkness, the researchers said. The animals also spent more time in the maize field and didn't appear very vigilant during these raids.
The steady spread of human activities and agriculture is destroying chimpanzee habitats in the area, so the animals may be adjusting their behavior to find new opportunities to forage, the researchers said.
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