The little blue blobs of jelly, whose Latin name is Velella velella, are harmless drifters which have no form of self-propulsion and rely on the wind and their translucent sail.
They have recently been found along the south and west coasts, most especially St Ouen’s Bay, after being blown across the Atlantic by the recent westerly and south-westerly winds.
By-the-wind sailors resemble the more exotic Portuguese man o’ war, which are occasionally found along the coast and washed up in their hundreds three years ago.
However, they lack the bright pink and purple sail – and potentially deadly sting – of their more fearsome-sounding lookalike.
Although both creatures look like jellyfish they are actually floating colonies of hydrozoans.
