After 'shark' watch now Cornwall is on alert for deadly Man O' War Just when you thought it was safe to go back in the water comes another threat to keep you out of the briney.
Instead of fabled sharks, swimmers and surfers have been warned to look out for killer jellyfish this weekend.
The warning comes after a Portuguese Man O' War was washed up on the shores of one of the most popular beaches in the UK.
It can deliver a sting from it long tentacles which can be fatal to humans and there have been several deaths in recent years.