![\"A](\"https:\/\/www.newsbeep.com\/uk\/wp-content\/uploads\/2026\/06\/SEI_302322602-3982.jpg\")
\n\t\tThe rare creature was found by a dog walker (Picture: Daily Post)<\/p>\n
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\n\t\tThe rare creature was found by a dog walker (Picture: Daily Post)<\/p>\n
A giant marine slug was found beached in Anglesey by a dogwalker, baffling some experts.<\/p>\n
The bizarre creature was later identified as a sea hare, a marine snail more commonly called a \u2018sea slug\u2019. <\/p>\n
Smaller sea hares are native to the UK, but the Trearddur is thought to be a much rarer creature, usually found in the Mediterranean. <\/p>\n
Emma Leese came across the sea hare some 20 metres from the water\u2019s edge at low tide. Worried that local dogs might take too much of an interest, she returned it to the sea.<\/p>\n
\u2018When back in water, it sort of unfolded,\u2019 she said. \u2018It began wriggling \u2013 slug-like \u2013 and its stalks began going back up.\u2019<\/p>\n
As sea slugs cannot absorb atmospheric oxygen, they typically die relatively quickly after stranding. <\/p>\n
When disturbed in water, they release a dramatic cloud of purple ink derived from the red algae they eat. <\/p>\n
Like the octopus, this ink is thought to provide a screen or act as a decoy to confuse predators.<\/p>\n
Owner and director of Anglesey Sea Zoo, Frankie Hobro, said it\u2019s more likely the creature is a depilatory sea hare.<\/p>\n
He added: \u2018This is still a rare UK species, found occasionally in southwest Britain. <\/p>\n
\u2018However, it\u2019s a species we\u2019re likely to see more of in the future as the seas warm and they keep moving north.\u2019<\/p>\n
According to the Global Biodiversity Information Facility, the Isle of Man<\/a> has three confirmed sightings of the depilatory sea hare, and north Scotland<\/a> has one. Wales<\/a> has none, though there have been anecdotal reports in Pembrokeshire.<\/p>\n As a mollusc, sea hares are related to the common garden snail. Instead of an external shell, they have a thin, transparent internal shell.<\/p>\n Their fleshy mantles have become modified into large, wing-like flaps. The depilatory sea hare can use these to gracefully swim through water \u2013 it is said to be surprisingly agile.<\/p>\n \t\t\t\tFollow Metro on WhatsApp to be the first to get all the latest news\t\t\t<\/p>\n \t\t Metro\u2019s on Whatsapp! Join our community<\/a> for breaking news and juicy stories.<\/p>\n Much more commonly found in the UK is the native spotted sea hare. This is usually around 7m long but can grow to 20cm. <\/p>\n In contrast, depilatory sea hares can reach 40cm, dwarfing their British cousins. They\u2019re also much bulkier.<\/p>\n Frankie advises anyone finding a sea hare not to touch them without gloves, as their skin stores noxious chemicals from their algal food. <\/p>\n \u2018They are quite revolting to touch. As they have quite strong suction, they should never be prised off a rock, as this may damage them,\u2019 he added.<\/p>\n \u2018I always say it\u2019s best to leave marine creatures alone, as it might not always be what you think they are.\u2019<\/p>\n Get in touch with our news team by emailing us at webnews@metro.co.uk<\/a>.<\/p>\n For more stories like this, check our news page<\/a>.<\/p>\n Arrow Arrow Arrow![\"Apps](\"https:\/\/www.newsbeep.com\/uk\/wp-content\/uploads\/2026\/06\/1782141433_124_GettyImages-1632181964-e1700130460337.jpg\")
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