The dangerous Lion's Mane jellyfish has been spotted at several Irish beaches.
The jellyfish has been reported along the Dublin coastline, and from Cork up to Donegal.
It has resulted in the public being warned to steer clear of several coastal locations.
Dun Laoghaire-Rathdown Council says warning signs have been erected at Sandycove, and lifeguards are "actively keeping a vigilant eye on the water".
John Leech is Chief Executive Officer of Irish Water Safety.
He says the Lion's Mane can reach more than 2 metres in length, and its sting is capable of putting people into anaphylactic shock.
