Man-Eating Lions Attack by the Dark of the Moon
If you want to avoid becoming a lion's dinner, keep an eye on the moon. A new study reveals that the big cats are most likely to attack people during the 10 days following the full moon. That's when it's darkest during the hours that humans are out and about at night—and when lions are at their hungriest.
Throughout Africa, people have killed most lions straying outside of nature reserves. Not so in Tanzania, where the big cats still roam freely in many areas. In a huge southern swath of the country, they have been attacking people with regularity. Between 1988 and 2009, lions ambushed more than 1000 people, killing and devouring two-thirds of them.
Ecologist Craig Packer, a lion expert based at the University of Minnesota, Twin Cities, began studying the situation several years ago, motivated, he says, to help protect Tanzanians from truly horrific deaths at the paws of a conservation icon. "No one ever forgets one of these lion attacks," he says. "They're indelibly etched in the memories of the survivors and the family members of the victims."
The attacks, he and his colleagues found, occurred mostly in rural areas inhabited by extremely poor farmers, many of whom sleep in their fields to protect their crops from bush pigs. These nocturnal marauders are just about the only lion prey left in a landscape largely converted to farmland. The lions stalk the bush pigs into the fields, where they sometimes stumble upon easier human prey. Lions hunt best when it's darkest out, and Packer's team wondered whether the amount of moonlight might also play a role in their attacks on people.
The researchers began by analyzing a data set maintained since 1978 on the belly sizes of lions living on ordinary prey in northern Tanzania, outside the man-eating zone. Big, full bellies indicate good meals, and these were hardest to earn as the moon waxed and prey could spot their attackers.
The team also pored over government records of lion attacks and visited 450 sites to interview victims or their families. When they plotted the attack dates against the lunar cycle, a clear pattern emerged. Nearly all attacks occurred after dark, 60% of them between 6:00 and 9:45 in the evening. Most striking, however, was the fact that the attacks were up to four times more likely on the 10 nights after the full moon. During that period, the moon rises later after sunset each evening, so the nighttime hours between 6:00 and 10:00 p.m., when people are most active, are dark. The lions are also at their hungriest because the hunting has been poor.