Beware the full moon, for as it fades, hungry lions emerge to reclaim the night — and prowl for human flesh. Scientists studying lion attack trends in Tanzania found that predation peaks in the evenings after a full moon. The finding is the first to link lunar cycles with predation on humans, long a source of superstition and lore.
The study, led by Craig Packer of the University of Minnesota Twin Cities campus, looked at the relationship between lunar cycles, lion attacks and lion feeding behavior. Researchers used records of more than 1,000 lion attacks on Tanzanian villagers that occurred between 1988 and 2009. Of these, nearly two-thirds were fatal, and most occurred after dark. Researchers were able to pinpoint a precise time of day for 474 attacks, and found that attacks clustered between 6 p.m. and 9:45 p.m.
They also found that attack rates were two to four times higher in the 10 days after a full moon. But periods of waxing lunar light were not similarly bloody. That’s because lions hunt best in darkness, the researchers report, and are hungry after nights of blazing, brilliant moonlight. Measuring lions’ belly sizes — and relative fullness — reveals a dip in food consumption during the full moon. So, as the lunar cycle wanes and nights slip toward inky darkness, lions compensate for their full moon fast by attacking humans.
“The full moon is not dangerous in itself,” the researchers conclude in the July 20 issue of PLoS ONE, “but is instead a portent of the darkness to come.”