Warning of sea lice bites at British lakes as swimmers report ‘nips’ and ‘stings’

Sea lice or jellyfish larvae thought to be responsible

Swimmers at two British seafront lakes have been warned of a potential abundance of flesh-eating lice – however stinging jellyfish larvae perhaps appear to be a more likely culprit.

People bathing in North Somerset have reported feeling “stings” and “nips” in the water at Clevedon Marine Lake and Weston Marine Lake.

The creatures responsible are suspected either to be sea lice or jellyfish larvae, according to the Marine Lake Enthusiasts Society (Marlens), the charity responsible for running the tidal pool at Clevedon.

“These critters get in the lake when the sea comes over the wall and they do bite or sting,” the charity wrote on Facebook.

“For most people, it’s just a little scratch sensation, but some of us more sensitive types can get a rash. The bad news is that there’s nothing we can do to stop them – it’s natural water and sea life lives in it, plus the water coming over the sea wall is much needed to keep the lake water fresh.

“The good news is that they go away after the overtop stops – if you want to avoid them, wait until next weekend for your swim.”

Advising swimmers to avoid the lake’s edges and patches of seaweed in the lake which tend to harbour more of the creatures, the charity added: “If you do have a bad reaction, speak to your pharmacist and avoid swimming until your skin clears up.”

Sea lice are commonly found on British shores and typically feed on salmon flesh. Despite their mouthparts being described by scientists as “adapted for tearing and macerating animal tissue”, they are not known to bite humans.

Somewhat confusingly, the term “sea lice bites” has become a misnomer used to describe stings from jellyfish larvae – also known as “seabather’s eruption” – which can cause a rash, in addition to nausea, vomiting, headache, and fatigue in some cases.

These larvae, generally half a millimeter in length and near-invisible once in water, can find their way into bathing suits, where they become trapped against the skin and will sting, according to the Divers Alert Network.

While this phenomenon is widely described in the Americas, the two species frequently blamed – thimble jellyfish (Linuche unguiculata) and the sea anemone, Edwardsiella lineata – are not found in British waters, however.

Regardless of the stinging creatures, Marlens urged would-be swimmers on Saturday not to use Clevedon Marine Lake, cautioning that the water quality there was poor.

Testing on 16 August showed the water quality had fallen below EU standards, the charity said, warning that this “means that there are more harmful bacteria in there than there should be”.

“Most people won’t get ill, but some may get ear infections or stomach bugs,” the charity said, adding that further testing would take place on Monday.