There has been an increase sightings of jellyfish on Irish coasts and beaches, with the Portuguese man o’war and the lion’s mane jellyfish the most frequent sea creatures spotted.

According to Water Safety Ireland, there have been more jellyfish cropping up in Irish coasts and beaches over the past seven years – this is due to the warming of sea waters, and over-fishing off Irish coasts, resulting in less predators to keep the number of jellyfish at a manageable level.

John Leech, CEO of Water Safety Ireland told that the Portuguese man o-war has been seen often again – after a record year of sightings last year.

They float on the surface of the water and when there’s a warm southerly wind, they blow them up to [Ireland]. They come from the tropics, anywhere around the equator, the West Indies, for example. In that whole area its common to see them.

He says the danger is that people in Ireland aren’t aware what the man o’war is, and might go over to investigate, then getting stung. “People can end up hospitalised,” he says.

If a child starts poking them they’re likely to get stung

“If you do see them, report them to the local authorities and they bury them. Even when they’re dead, the venom stays in them for a few days.”

Although Water Safety Ireland (IWS) has received an increase in the number of reported man o’wars, they’ve had no reports of injuries.

The lion’s mane jellyfish is another increasingly common sea creature in Ireland. He says there’s been an overall increase in jellyfish because of an increase in water temperature and over-fishing.

We don’t have enough natural predators, or fish that eat jellyfish,” Leech says. “We don’t have the same degree of fish, a lot of EU countries are fishing in our waters at the moment, so the number of fish has reduced and they’re not eating as much as they should have.”

The consequence of an increase in jellyfish along Irish coasts is for swimmers and walkers. “It’s a big swimming concern,” Leech says. “Some bathing areas had to be closed down last year right around the country from Clare to Dublin.”

If you do see a jellyfish like creature (the man o’war isn’t technically one, it’s a group of organisms that travel together) here’s what the IWS says you should do:

  • Make sure you don’t get stung yourself when helping others
  • Remove any attached tentacles with a gloved hand, stick, or towel
  • Do not rub the affected area, as more venom could be released
  • Rinse the affected area copiously with sea-water (do not use fresh water, vinegar, alcohol or urine)
  • Apply a “dry cold pack” to the area (i.e. place a cold pack or ice inside a plastic bag and then wrap this package in a t-shirt or other piece of cloth)
  • Use hot water for portuguese man o’war stings at around 45 degrees for 20 minutes
  • Seek medical attention if there is anything other than minor discomfort
  • If you suffer from swelling, breathing difficulties, palpitation or chest tightness after being stung, go to the nearest emergency department urgently.