A new report from University of Hawaii researchers sheds light on the behavior of box jellyfish near Waikiki, where the gelatinous creatures have flourished in recent decades and now sting thousands of ocean-goers each year.
It’s actually a lack of light that triggers the jellies’ “clockwork” migration into the shallow waters right off that popular visitor destination, according to the peer-reviewed UH study, which appears in the June issue of Regional Studies in Marine Science.
Researchers found that the creatures swim toward shore on the nights in the lunar cycle when there’s an especially long period between twilight and moonrise – and that they do so in order to spawn. The box jellyfish reliably appear near shore eight to 10 days after the full moon. The study, however, looked at why that is and what causes them to do so.