This video made on August 20, 2019 documents the invasion of Mnemiopsis leidyi ...

And also this summer we found ourselves faced with the now regular invasion of the Sea walnut, Mnemiopsis leidyi (warty comb jelly or sea walnut). This phenomenon is becoming more and more frequent throughout the summers, and it is now clear that the main cause of these invasions is the increase in sea temperature. ...

Also this summer we are witnessing the invasion of the Mnemiopsis leidyi or Sea walnut. This year we are in early July and the sea water is slowly warming up as always in summer. Punctually after a short and intense sea storm we witness an invasion of jellyfish, plastic, tree trunks and branches, various floating debris and as now every year also the Mnemiopsis leidyi, the now infamous Sea walnut. ...

We are now facing a real tropicalization of the Mediterranean Sea which is leading to a too rapid and rapid change of this ecosystem, so we are increasingly witnessing an invasion of alien species, explosions of mucilage and toxic algae, a decrease in native fish species, a reduction in fishing and catches and, as can be seen from these images, a proliferation of jellyfish ...