The seas are warming and jellyfish are multiplying; the Mediterranean is also threatened by “alien” species

During the summer season, jellyfish continue to be one of the main concerns for holidaymakers.

The steady rise in seawater temperatures is encouraging the mass proliferation of these creatures, which are among the planet’s earliest multicellular organisms.

According to an alert issued by the Italian media, foreign species that could pose a risk have also been identified in the Mediterranean, including the Portuguese man-of-war. In fact, it consists of colonies of small organisms living together and has extremely long tentacles that deliver a powerful sting.

In Sicily, in 2022, contact with one of these jellyfish resulted in a woman being rushed to hospital. Meanwhile, in 2010, a 69-year-old woman died in Sardinia.

Originating in the Atlantic Ocean, the Portuguese man-of-war has been spotted sporadically in the Mediterranean for decades. This year, so many specimens were reported along the Spanish coast that some beaches were forced to close temporarily. Over the past 20 years, the jellyfish population in the Mediterranean region has increased almost tenfold.

Marine biologists explain that sea currents carry jellyfish, which tend to gather in large groups, especially during the breeding season. As a result, some areas may give the impression that the waters have been overrun by them, while in other areas they are almost entirely absent.