Thousands of spider crab carcasses found on beach in Anglesey

Thousands of spider crab carcasses blanketed a beach in Anglesey, creating a sea life spectacle at the coastal spot.

Initially sparking online concern about a possible mass die-off event at Traeth Mawr, experts were quick to explain the natural phenomenon that had taken place.

These remnants belong to the spider crab, which is known for its spiky exterior and elongated limbs.

Part of a growth cycle is critical to the spider crab's development, the annual mass moulting occurs when they congregate in shallower waters during the warmer months.

As they shed their exoskeletons, they briefly become defenceless against predators until their fresh armour develops.

This migration and subsequent moulting safeguard them collectively in numbers off the British coastline as summer temperatures rise.

The process creates a feast for predators, including some locals who seize the opportunity to collect the live crabs found along the beaches of Anglesey for culinary purposes.

Nearby beaches such as Malltraeth also witness similar scenes each year, making Anglesey a prime location for observing this impressive natural event.

As sightings of these crustaceans increase along British shores, some theorise that climate change could be driving the rise in numbers.

Beach wash-ups, like those on Anglesey, are often reported to Natural Resources Wales for tracking purposes.

The sight is not one of doom but rather an indication of a thriving ecosystem, says Frankie Hobro, director of Anglesey Sea Zoo.

Home to an array of spider crabs, which boast substantial leg spans reaching 50cm, the zoo celebrates these marine wonders.

Speaking to the Daily Star, she explained: "These crab remains can be quite alarming but they are quite amazing-looking things, they're very spiny, almost like alien beings.

"It's not surprising that people are concerned it may be a mass die-off. But it's actually a positive sign as it shows there are thousands of spider crabs out there growing and breeding."

In an eerie underwater spectacle, the spider crabs are shedding their sharp carapaces and appendages, including legs, claws, and even eye-stalks as they grow.

The cast-offs, reminiscent of a snake's discarded skin, accumulate on the ocean floor but often get washed up on beaches, creating quite a sight for coastal visitors.

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