Of the 15 or so species recorded regularly in British seas, the species known as the Common Hermit Crab, Pagurus bernhardus , is by far the commonest. If the major claw is on the right side nearest the apex, you can almost certainly assume that a Hermit Crab found between the tides is this species. All the others are so unusual as to be worth a mention in the ' Shorewatch' Newsletter. Squabbles Continual fights and squabbles are the result of keeping several Hermit Crabs in the same aquarium. This can be explained by the need for the crab to protect its soft abdomen with a borrowed shell.
Fights occur when the crabs dispute the available shells.
In the Common Hermit Crab , Pagurus bernhardus , the eggs hatch into larvae in the first two months of the year. At this hazardous stage they will undergo moults like all crustaceans. The first planktonic stages are called zoea . Hermit Crabs are widespread on different demersal habitats, and the choice of shell depends on what is available. Pheasant Shells, Tricolia pullus , and Little Netted Dogwhelk Shells, Hinia incrassata , are a popular early choice on mid-Sussex shores.