Thousands of shells cover ‘nudist beach for crabs’ in Wales, turning it into crustacean cemetery
Strollers along the shores of Anglesey were treated to a surprising sight as they came across thousands of peculiar-looking crabs strewn along a mile-long stretch of Aberffraw’s Traeth Mawr (Big Beach). The beach appeared to have been taken over by a vast collection of crab shells in what seemed like a massive crustacean graveyard following a mass stranding event. Witnesses described encountering layers of reddish-orange crab shells, some even found as far as 500 meters away on a riverbank near the village. The crabs, adorned with jagged points and some covered in algae, left dog walkers quite unnerved, with one stating, “You wouldn’t believe how scary they were.”
This recent occurrence is just one of many similar events that have taken place this year. While many of the observed shells were empty, there were also reports of complete crabs being spotted. Marine experts were quick to allay any concerns, affirming that the phenomenon is a regular and seasonal occurrence. These eerie deposits are in fact the exoskeletons of spiny spider crabs, which are known to gather in large numbers offshore to shed their shells as part of their growth process. Frankie Hobro, the owner of Anglesey Sea Zoo, reassured the public, saying, “It may look alarming but there is nothing to be concerned about. It is, in fact, an amazing natural phenomenon.”
Spiny spider crabs typically move to shallower waters in warmer temperatures to feed and shed their exoskeletons, which then accumulate on the ocean floor. Factors like storms, high tides, and currents often result in these old shells being washed ashore. While Devon and Cornwall are commonly known for hosting vast numbers of crabs offshore, Aberffraw is notable for its impressive gatherings, attracting visitors keen to witness the spectacle. Last week’s occurrence likely marks the final crab shell wash-up of the season in Anglesey, signifying the end of a successful period for the local spider crabs.
These spider crabs play a crucial role in maintaining the seabed by consuming dead fish, invertebrates, and algae. They are an integral part of the ecosystem, with their feeding habits contributing to a healthy marine environment. Despite the striking visuals of the beach wash-ups, they offer only a partial view of the underwater scenes. Earlier in the summer, it is likely that females shed their shells, followed by larger males after the breeding season, leading to the recent wash-up. When these events are considered together, they paint a truly spectacular picture for those willing to explore beneath the surface.
While the crab-covered shores of Aberffraw may be fascinating to behold, they also pose a risk to those wandering the area. Measuring between 5-20cm in length with bodies covered in sharp spines, the crabs can be painful to step on with bare feet. Frankie advises caution, stating, “As their name suggests, their shells can be very spiky. So, avoid treading on them with bare feet – it can really be quite painful!” Should anyone come across unusual marine life on the shores of Anglesey, it is recommended to contact Anglesey Sea Zoo for assistance. Quick reporting of strandings could aid experts in rehabilitating creatures found, even if they appear lifeless.
In conclusion, the ‘nudist beach for crabs’ at Aberffraw has once again mesmerised onlookers with its natural spectacle, showcasing the wonders of marine life and the intricate processes of growth and renewal in the underwater world.