What chimps want, chimps get.
Researchers from the Uganda Wildlife Authority and Paris' Museum of Natural History teamed up to film chimpanzees raiding corn fields for food. The animals had to adapt to humans encroaching on their natural habitat and they did that by venturing into farms.
Chimpanzees raiding farmland is not unheard of but incidents usually happen during the day, never after sunset. As the captured footage shows chimps active in the dark, researchers were surprised. This is because chimpanzees have not been known to have special faculties that would help them see at night. The captured footage was in total darkness, with no moon out, so researchers didn't know how the chimps were able to move around effectively.
Published in the journal PLOS One, the researchers' work was the first video proof of a nighttime raid involving chimpanzees. Camera traps were set at the Kibale National Park, on a border shared with a corn plantation in 2013, for 20 days.
During that time, chimps were observed to be using a fallen tree as a bridge to get to the plantation, in a total of 14 raids. There was a 6.5-foot-deep, 6.5-foot-wide trench separating the forest the chimpanzees call home and the corn field but that was not a problem.
Aside from baffling researchers how they can move so efficiently in the dark, the chimps also offered other revelations. For one, they were engaging in raids in bigger groups, going from the usual three to an average of eight in every group.
They also didn't discriminate on which chimps would participate in raids, with groups often including females with infants. Sometimes females would even be leading groups.
The chimps also didn't eat their loot on site, often leaving the fields holding stems or ears of corn in their hands or gripping them in their teeth.
"Even though the chimpanzees' home range has been seriously damaged and disturbed by both logging activities and significant human demographic pressure, chimpanzees have shown great behavioral flexibility including unexpected nocturnal behavior, in order to take advantage of the proximity of domestic nutritive food," concluded the researchers.
While done out of necessity, raiding farmland can be dangerous to a chimp. As it is, chimpanzees are endangered due to disease, poaching, and loss of habitat. By venturing into human territory, chimps risk getting hurt by people trying to keep them from taking food. Some people can also be harsher, killing raiders in an attempt to deter other chimps.