Hundreds of vibrant blue 'by-the-wind sailors' have been washing up on Welsh beaches, captivating locals with their striking appearance. The creatures, Velella velella, have been spotted along Anglesey's coastline, as well as in Gwynedd and Tenby.
These free-floating hydrozoans are propelled across the ocean surface by wind due to a small, sail-like structure on their back. One beachgoer described finding them 'like crystals' – an apt description given their sparkling blue hue that catches the sunlight.
Marine specialist Frankie Hobro from Anglesey Sea Zoo warns against touching these creatures, which are related to the venomous Portuguese man o' war but significantly smaller at approximately 7cm long. While their sting is considered mild, it can cause discomfort – particularly if sensitive areas like the lips or face come into contact with them.
By-the-wind sailors typically appear during autumn and winter months as ocean currents carry them across vast distances. Large groups often 'dump' ashore simultaneously following storms or shifts in tides, leaving their stinging cells active even when they appear dead.
While their appearance may be mistaken for the Portuguese man o' war due to their striking blue colour, Hobro notes that by-the-wind sailors are noticeably smaller. She advises admiring these creatures from a safe distance to avoid irritation and appreciate their unique qualities without risking discomfort.