A WARNING HAS been issued to beachgoers after Lion’s Mane jellyfish have been spotted at Malahide Beach in Dublin over the past few days.

Fingal County Council has urged the public to be aware of the jellyfish, saying that they may be spotted at other beaches over the coming weeks.

Conditions for the jellyfish are ideal at this time of year, the Council has warned, advising that from the middle of August up to the second week of September there may be a “noticeable increase” in the numbers of jellyfish on beaches and in the water.

It wouldn't be summer if there wasn't some jellyfish spotting going on! With that in mind, beachgoers should be aware that there have been sightings of Lion's Mane #jellyfish at #Malahide Beach in the last few days, and they may also be spotted at our other beaches over the… pic.twitter.com/MMWXFH8LAl

— Fingal County Council (@Fingalcoco) August 13, 2024

Lion’s Mane jellyfish are typically around 40cm long but can grow to be even larger with some known to get up to 200cm long.

A sting from a Lion’s Mane jellyfish can cause nausea, sweating, cramps, headaches and other symptoms, with the Council urging bathers to be “extra vigilant” on beaches where the jellyfish are found.

The public should also be cautious of jellyfish that have washed up and appear dead, with the venom able to remain in the tentacles for a few days after death.

Fragments of the jellyfish’s tentacles that break off and float around in the water can also still sting.

Lifeguards may raise a red flag to advise against swimming if a large number of Lion’s Mane jellyfish are in the area and the Council has asked the public to respect these flags.

If you are stung by a jellyfish, approach the lifeguard if possible and seek medical attention for any serious symptoms.

Anyone who is stung should not use fresh water or alcohol on the affected area, and should not urinate on the affected area.  

It is also not advised to rub the affected area or cover it with a tight bandage. 

Further first aid advice, as well as the jellyfish ID card, is available on the HSE’s website.