Beach users have been warned to beware of stinging jellyfish after an "unprecedented" number of reports of the creatures being stranded across the UK.
The Marine Conservation Society (MCS) has received more than 60 reports of Portuguese-Man-of-War, a jellyfish-like creature, stranded on beaches on the Isle of Wight, Devon, Cornwall, Wales and the Isle of Man in the past six weeks.
It also received reports of a mass stranding of the mauve stinger jellyfish on the Isle of Lewis last week, as part of its national Jellyfish Survey.
MCS said it was the third consecutive year that large numbers of the species have been recorded late in the year on the west coast of the UK. Large swarms of mauve stingers can have economic consequences, the MCS said, killing caged fish in fish farms and making the sea hazardous for bathing, affecting the tourism industry.
Peter Richardson, MCS biodiversity programme manager, said: "Between 2003 and 2006 the MCS jellyfish survey received less than 10 reports of Portuguese-Man-of-War, but in the summers of 2007 and 2008 they started stranding on beaches in the South-west in greater numbers. This summer we have received over 60 reports involving hundreds of Portuguese-Man-of-War – many more than in previous years. We are urging the public to help us record these jellyfish swarms so we can warn relevant local interests, such as fish farms, about their arrival.
"We encourage anyone who encounters a jellyfish to download our free identification guide, carefully identify and then report the jellyfish to our survey online at the MCS website."