To avoid jellyfish stings, follow the moon cycle

September 7, 2016, 4:15 p.m.
School of jellyfish
Photo: divedog/Shutterstock

The moon might be a factor in knowing when to stay out of the water to avoid jellyfish stings. New research out of Israel draws a correlation between the phase of the moon and when jellyfish swarm.

PhysOrg reports:

In the middle of the lunar months — the days before and during the full moon — jellyfish are far more likely to swarm the beach, potentially stinging humans, the research found. "We were surprised by our findings," researcher Avi Algazi told AFP. "We knew the moon has a big influence on a lot of things but we didn't so far have statistical data on the correlation between jellyfish and the moon." The research was conducted by the Israel Electric Corporation in conjunction with the University of Haifa in northern Israel.The jellyfish are a threat to Israel's power supply as they get sucked into the country's main power station, which uses sea water for cooling.

Algazi suspects that the moon's light may trigger reproduction for jellyfish, hence the swarming behavior near full moons.

While the study is useful for these specific power plants and predicting when swarms may clog the cooling systems, the findings could also be useful for beachgoers who can use the lunar calendar to judge when a seaside swim is a good idea — or not. The study was conducted for the local area only, but it raises interesting possibilities about other parts of the world as well.