After jellyfish, it is the “fireworm” which could spoil the pleasure of swimmers in summer: its burns are sharp and can cause nausea.
As summer approaches, vacationers are accustomed to seeing signs on some of their favorite beaches reading “beware of jellyfish.” But this year, another marine animal could spoil the joy of swimmers. For some time now, biologists from the Sicilian centers of Panarea and Milazzo, attached to the National Institute of Oceanography and Experimental Geophysics (OGS), are concerned about the arrival of a worm with stinging capabilities on Mediterranean beaches. This is a marine worm called Hermodice caruncutala, normally present off the island of Malta and the coasts of the Maghreb, which is found today in the sand and sea grass of the northern coasts of the Mediterranean.
Closer to the centipede than to the earthworm, the fireworm usually measures between twenty and thirty centimeters long. In the water and on the beaches, it stands out particularly for its bright colors, varying between red, green, gray, yellow and white. But if some people find it rather pretty, they had better be wary of it. Not only is it a worm that feeds on animals and carrion, but it is also surrounded by a kind of white silk that releases venom. You should therefore definitely not touch it. This is where the name “fireworm” comes from.
If its presence in large numbers near coasts and swimming areas is worrying, it is because, like jellyfish, it releases an extremely irritating venom on contact with the skin. This venom causes skin burns and swelling that can last for several hours. In some cases, the pain is so great that it can lead to dizziness and nausea. Like jellyfish on our beaches, the sting of the fireworm is not fatal for humans but will certainly cause significant and lasting discomfort.
Normally endemic to warm maritime areas of the Atlantic Ocean, the fireworm has also been present for several years in the eastern part of the Mediterranean Sea. Its presence in the south of Italy and on the Sicilian coast was known, but researchers note that the worm is gradually moving northwards, particularly in the Tyrrhenian Sea.
This gradual migration could be explained by the increase in water temperature which would also favor the proliferation of the species, observed the biologists. According to them, the successive heat waves of recent years have also allowed this worm to multiply and move into spaces where it had not yet been observed. For the moment, it is not the subject of a particular alert in France.
The fireworm is not only a risk for swimmers who come to enjoy the warm, turquoise waters of the Mediterranean, it is also a risk for fishermen. The increase in the number of individuals in fishing areas, where it comes to feed, is harmful, because it is very often found in nets. In addition to giving more work to fishermen, since they must take certain precautions to extract them, the fireworm kills the fish that provide their income. This is what alarmed the Italian fishermen who then contacted the OGS biologists who are now dealing with this subject.