Anyone venturing into the sea this summer will be aware that they are not alone, as jellyfish make their annual visits to the islands. Natalie Bowen learns how best to avoid them – and gives some tips for treating their inevitable stings.
Jellyfish can be a menace in Maltese waters, floating into bays and spoiling summer days for thousands who want to play in the sea.
But with a few precautions and sensible behaviour, there is plenty of space for both humans and jellies, without painful stings.
The most dangerous species found around the islands are the Portuguese man o’ war (Physalia physalis) and the box jellyfish (Carybdea marsupialis), but these are infrequent visitors, according to marine biologist Alan Deidun.
“The mauve stinger (Pelagia noctiluca), although somewhat less dangerous, is much more common in local waters,” he says.
Dr Deidun explains there are more types of harmless jellyfish around Malta, but the few venomous species tend to arrive in greater numbers – particularly the mauve stinger – “and that’s why they make the headlines”.
Divers may think a wetsuit will keep them safe, and indeed a thicker suit will offer more protection from stinging tentacles, but the biologist warns that areas such as the hands, may still be exposed.
Strategic thinking can help snorkellers and other water sports enthusisasts avoid danger areas: for instance, yacht marinas and harbours are fertile grounds for the box jellyfish.
“During the night, the mauve stinger sinks to lower water levels and hence is more difficult to spot,” says Dr Deidun – a good warning for nocturnal divers.
Sadly, there is no definite rule about whether jellies are more likely to be close to beaches, posing a risk to swimmers and surfers, or further out at sea where they may encounter kayakers.
“It all depends mainly (but not exclusively) on the prevailing wind and sea current conditions in the area as jellyfish are planktonic and cannot oppose prevailing sea currents,” explains Dr Deidun.
“So far, luckily, we have had very few incidences of massive blooms that infect the water over huge areas and for days on end.
“And the species most frequent in our waters are less dangerous than those found in other parts of the Med, such as the nomadic jellyfish in Israel and Lebanon.”
If anyone inadvertently gets caught in a bloom, his advice is: “Hold your breath, dive and swim laterally under the surface as far away as possible.”
Infamous ‘cures’ for tentacle stings, such as vinegar and urine, may not help either, he adds.
“There are very few rules that are valid for all jellyfish since the treatment actually depends on the species in question. While vinegar might be a valid treatment for some species, in others it might actually make the pain worse.”
Two rules that apply to any species include avoiding scratching the welt and washing it with sea, not fresh, water.
Dr Deidun coordinated the Spot the Jellyfish initiative, a campaign that started in 2011. Placards featuring pictures of common jelly visitors have been put up at hotspots and people can send an SMS detailing the date, time and number of jellies seen to 7922 2278, by sending an e-mail to ioi-moc@um.edu.mt or by filling out a form at http://193.188.45. 233/ jellyfish/ReportForm.html. An app is also being developed to share sightings with smartphone users.
Common visitors
Clockwise from top left: Crystal jellyfish (Aequorea victoria), Mauve stinger (Pelagia noctiluca), Moon jellyfish (Aurelia aurita), Fried egg jellyfish (Phacellophora camtschatica) and Australian spotted jellyfish (Phyllorhiza punctata).