Pagurus bernhardus is the common marine hermit crab of Europe's Atlantic coasts.

Its carapace reaches 3.5 centimetres (1.4 in) long,[2] and is found in both rocky and sandy areas, from the Arctic waters of Iceland, Svalbard and Russia as far south as southern Portugal, but its range does not extend as far as the Mediterranean Sea.

P. bernhardus is an omnivorous detritivore[3][4] that opportunistically scavenges for carrion,[5] and which can also filter feed when necessary.

[6] Pagurus bernhardus uses shells of a number of gastropod species for protection, including Littorina littorea, Littorina obtusata, Nassarius reticulatus, Gibbula umbilicalis, Nucella lapillus and Buccinum.

[7][8] In the warmer parts of its range, the sea anemone Calliactis parasitica is often found growing on the shell occupied by Pagurus bernhardus.