Swimmers and coastal visitors are being urged to photograph and report any sightings of lion's mane jellyfish in Galway.
A recent increase in lion’s mane jellyfish sightings has resulted in swimmers across parts of Ireland being stung - the aquatic animal having been reported in Salthill, Kinvara, Carna and Oranmore,
Jasmine Headlam, PhD and Fullbright researcher from the Ryan Institute at NUI Galway, says lion’s mane jellyfish are often seen on the east coast, where the water is cooler.
"In the last few weeks we’ve had reports of large adult lion’s mane from the west coast in Galway, as well as Newquay in Clare and even Cork harbour. We urge sea swimmers and coastal visitors to report any sightings, with photographs if possible, to the National Biodiversity Data Centre website and the Big Jellyfish Hunt Facebook page.
“Lion’s mane stings, though not generally considered fatal, can cause a lot of pain. Stings from large lion’s mane can be particularly dangerous, as the thousands of thin tentacles can each extend to several metres long. Initially, a sting may result in itching or localised pain that may radiate to other areas of the body, potentially progressing to severe pain within 20 minutes or more. In some cases, stings can result in Irukandji-like syndrome. This syndrome, named after a type of box jellyfish, can involve symptoms including back pain, nausea, abdominal cramps, sweating and hypertension.”
Research published by NUI Galway in the international journal Toxins in 2017 showed the best first aid treatment for a lion’s mane sting is to rinse with vinegar (or the commercial product Sting No More® spray ) to remove tentacles, and then immerse in 45°C (113°F ) hot water (or apply a heat pack ) for 40 minutes.
The lion’s mane jellyfish is a large jellyfish (up to one metre bell diameter ) with thousands of long tentacles located beneath the bell. In Irish and UK waters, lion’s mane jellyfish can be encountered from June until late September. It is one of the least abundant jellyfish in Irish and UK waters, typically occurring as single individuals rather than in blooms or aggregations. Despite being one of the least abundant jellyfish, relatively high densities of large lion’s mane jellyfish have been recorded close to high population areas in recent weeks, and therefore stings have been a recurrent concern. Five people have now been hospitalised after being stung.
Dr Tom Doyle, zoology lecturer at UCC’s school of biological, earth and environmental sciences, will meet with the Beaumont Poison Centre at Beamount Hospital Dublin to discuss these findings in the next few weeks.
“Lion’s mane are spreading geographically, with sightings in the Celtic Sea and Atlantic waters in recent weeks. It is not correct to say this is the first time they have been spotted on the west coast, as we had reports for the last two years, but they are particularly large and mature. The typical jellyfish lives in the water column for six to eight months, having been released as a juvenile in December, but we believe these jellyfish may have over-wintered and may be on their second season.”