Wild Chimps Have Become Nighttime Crop Raiders to Cope With Their Disturbed Habitat

Wild chimps may be developing innovative strategies in order to cope with living in disturbed habitat. Scientists have found that chimps actually have begun foraging crops at night in an effort to deal with encroachment by humans.

People continue to expand land use for agriculture and other activities. This expansion continues to encroach on wild chimpanzee habitat, which is why researchers wanted to see exactly what the chimps were doing in terms of adjusting. In order to find that out, the scientists used camera-traps to watch chimpanzee behavior during incursions out of the surrounding forest into corn fields in Kibale National Park in Uganda. Over the course of 20 days, the researchers found that the chimps raided the crops 14 different times.

More specifically, the researchers witnessed large parts of eight or more chimps, which is more than double the median of the party size of three chimps of the same community during feeding activities in the forest, raid the crops. These groups didn't just include males and single females, though; they also included females with clinging infants. Not only that, but the chimps seem to be doing more of their crop-raiding during night, which is a previously undocumented and normally risky behavior. That's not all the researchers noted, though. The groups of chimps stayed longer in the crop field and presented few signs of vigilance and anxiety during these raids.

The findings reveal a way in which chimps are adapting to human encroachment. By raiding crops at night, they can harvest a valuable food source as their own, natural food sources are being taken away. As human expansion continues and as wild chimp populations decline, it's more important than ever to take these coping behaviors into account when planning conservation efforts.

The findings are published in the journal PLOS One.