Jellyfish
Jellyfish are seen in a tank during a media tour before the opening of the Inbursa Aquarium in the wealthy neighbourhood of Polanco, in Mexico City May 30, 2014. Reuters/Tomas Bravo

Israeli scientists advise beach goers to observe the sky if they want to avoid being stung by jellyfish. A study by the Israel Electric Corp and University of Haifa’s Department of Natural Resources and Environmental Management discovered the Hebrew lunar calendar is a good guide on timing of jellyfish arrival on Mediterranean shores.

Jellyfish likely would swarm the beach before and during full moon, on the middle of Hebrew lunar months, reports ABC. Researcher Avi Algazi admits being surprised by their findings.

“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,” Algazi explains.

The electric company made the study because of the threat to electric supply posed by jellyfish. Israel’s main power station uses sea water for cooling, but jellyfish are sometimes sucked into the power station.

The study observed when the power station was most badly affected by the jellyfish and correlated it with moon and water temperatures. The researchers found that 94 percent of jellyfish swarms arrive midyear at a time when seas are warmer and during the second and third weeks of the Hebrew lunar month. Jellyfish prefer water that have temperatures between 28.2 and 30 degrees Celsius.

The scientists did not discount the possibility that individual jellyfish would also reach the coast during other conditions, although the most significant swarms come during the conditions mentioned earlier, notes Sciencedaily. The electric company’s five power stations are found along the coast of the Mediterranean Sea.

While the blockage of the cooling system filters caused a small decline in electricity generation, it made up a significant part of operational costs of the cooling system, Algazi says. When jellyfish are sucked into the cooling system, some block the moving filter after penetrating it, preventing seawater from being pumped in and causing the cooling pump to stop immediately.

Algazi stresses the findings apply to local conditions, although he hopes “the results could be checked in other parts of the world.”

VIDEO: Israeli power plants threatened by jelllyfish

Source: AFP news agency