Jellyfish to Arrive Early This Year, but It Could Be Worse

The annual jellyfish invasion appears to be hitting Israel's shores early this year, according to sightings reported yesterday by local fishermen. The stinging invertebrates generally don't arrive en masse until the end of June.

Israelis are not the only ones to suffer from an increased dose of jellyfish. Their presence has been growing around the world, according to a recent article in the London-based journal Trends in Ecology & Evolution.

In addition to swarming Israel's Mediterranean shoreline, from Acre in the north to Ashkelon in the south, jellyfish also turn up on the coasts of Japan and Namibia and in the Mexican Gulf and the Black Sea, among other sites noted in the article. Israelis should consider themselves lucky; while the nomadic Mediterranean jellyfish (Rhopilema nomadica) extend to several dozen centimeters in diameter, Japan has recently been host to jellyfish as large as two meters in diameter, which weigh as much as 200 kilograms.

In addition to stinging bathers, jellyfish also prey upon local sea animals, compete with them for sustenance and endanger fish that are bred in cages at sea. But humans are not just the occasional victims of jellyfish: They can also be the cause of their influx, the journal article found.

Indeed, it pointed out that unsupervised fishing and pollution are among the primary causes of the jellyfish invasion, because they have brought about changes in the marine ecological system, including the disappearance of the jellyfish's natural predators.