Noticed a little shell scurrying across the beach? You might just have seen a hermit crab! Found in rockpools, shorelines and deep sea waters, these little house hunters are found widespread around the British coast.
Unlike other crabs, hermit crabs aren’t born with a shell. They have hard pincers, but a soft vulnerable body which is why they seek out homes in empty mollusc shells. As the hermit crab grows bigger, it will abandon its overly snug shell in favour of a larger home.
Fossil records show hermit crabs using old mollusc shells way back to the Late Cretaceous period, nearly 100 million years ago. But before this some hermit crabs used ammonite shells, a now extinct group of marine molluscs.