What’s beneath your feet? (Dr Tegwyn Harris)

6th June 2012

Bar beach, Helford Passage

On a slightly blustery afternoon an intrepid group of Helford VMCA members headed out on to Bar Beach to explore the squidgy, muddy but intriguing world living beneath our feet. The event was planned to find, identify and learn a little more about some of the unusual critters to be found hidden in the muddy shores of the Helford River. We all see the mud shores, but to many of us they usually look muddy, flat and not terribly alive, so on this afternoon Tegwyn set out to prove just how much life was there, if only you open your eyes and look.

At the start of the event we promptly headed down to the bottom of the shore to begin our exploration. The first thing you notice is that the mud isn’t flat and barren – it is covered in holes, burrows, trails, mounds and strange little structures created by all of the critters living within it. With a few volunteers armed with spades, trowels and buckets it didn’t take long for us to start finding out what had made them. Tegwyn was brilliant, pitching information about the creatures we found at a level understandable by everyone from young children to marine scientists and featuring fantastic analogies including the equivalent of living on essence of fish and chips and body-snatching Hollywood aliens! We found masked crabs (Corystes cassivelaunus) which burrow into the sediment and breathe through a filtering snorkel formed from two antennae, common shore crabs (Carcinus maenas) whose body had been taken over by a parasitic barnacle which occupies its tissues and a range of bristle worms which, although often overlooked, are equally as beautiful and quirky as many of the other more familiar creatures.

Special thanks should go to Dr Tegwyn Harris for his wonderful, animated discussions on the lives of the creatures beneath our feet and for sharing some of his immense knowledge on this subject. Thanks also go to all the Helford VMCA volunteers who turned up, dug in and got muddy and to Matt Slater (Cornwall Wildlife Trust), Rhiannon Pipkin (Natural England), Pamela Tompsett and Dave Thomson (Helford VMCA) for organisation, logistics and making sure everything ran smoothly!

A full list of species found on the day can be found here.

Holly Latham

Masked Crab (Corystes cassivelaunus). Image: Holly Latham
What’s beneath your feet? Image: Pam Tompsett

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