No invasion of Portuguese Man-of-War jellyfish in the Mediterranean this summer

The Joint Research Centre of the European Commission expects swimming in the Mediterranean to be safer this summer, as sightings of the dangerous Portuguese Man-of-War jellyfish decline. Although the Portuguese Man-of-War (Physalia physalis) is not a native species in the Mediteranean basin, the region experienced a high number of swarms in 2010 that had dramatic consequences, including the first human fatality caused by a jellyfish sting (near Cagliari, Sardinia). Despite the impact of jellyfish on coastal economic activity and the importance of the tourism industry for the Mediterranean region (accounting for 15% of global tourism), no scientific consensus has been achieved regarding the causes of this episode, JRC said. "Based on analyses and simulations, the authors conclude that the 2010 event was the result of an unusual combination of meteorological and oceanographic conditions and not a permanent invasion," the centre said.  The researchers found that the values during the winter of 2009-2010 of the North Atlantic Oscillation (NAO, a climatic phenomenon in the North Atlantic Ocean which has a strong effect on the wind and precipitation patterns of Europe) were among the...