THOUSANDS OF DANGEROUS Portuguese man o’war jellyfish have washed up along the west and south-west coast of Ireland. 

The man o’war is considered much more dangerous than regular moon jellyfish commonly found in Irish waters, and is usually found in warmer waters.

While there have been previous sightings of the creatures in Ireland, they have never previously arrived in such high volumes, with Dingle Oceanworld director Kevin Flannery putting the latest arrival in the thousands. 

He credits last week’s Storm Lorenzo as the reason for the latest invasion. 

“The infamous Lorenzo came direct from the Azores and these jellyfish are like floating balloons on top of the water,” he said.  

“Usually jellyfish would be under the water but these guys are on top. So when you put them in the middle of a hurricane, which Lorenzo was when he hit the Azores, they are displaced and blown up to our waters.”

While traditional jellyfish stings are usually treated with general first aid but a sting from the Man O’War can lead to more sinister symptoms. 

“If you’ve ever fallen into a handful of nettles or you’ve been splashed with boiling water then you know the sting. 

“They are seriously a lot more painful. The top of the balloon is OK to touch but the the tentacle is what they use to kill their prey. The minute they touch anything the will release their venom and it anesthetises their prey.”

“People who have breathing difficulties or young children are particularly at risk,” he added.

While the path of Lorenzo lead to them landing on Irish shores, the likelihood of them breeding in Irish waters is slim.

“They prefer warmer climates and it is basically only because they were inflated that they got thrown towards us.”

The jellyfish have been spotted along the west coast from beaches in Kerry right up to Mayo. 

In a statement online, Galway City Council warned local residents to be careful while walking along the coast. 

“A man-of-war sting is extremely painful and even dead ones washed up on shore can deliver a sting. The public are advised to exercise caution in the vicinity,” it said.