Hermit crabs are decapod crustaceans of the superfamily Paguroidea. Most of the 1100 species possess an asymmetrical abdomen which is soft, unlike the hard, calcified abdomens seen in related crustaceans. The vulnerable abdomen is concealed in a salvaged empty gastropod shell that is carried around by the hermit crab into which its whole body can retract.
As a part of my undergrad field course, myself and my peers did a mini project titled “Competition Behaviour and Shell Preference in Anapagurus laevis (hermit crab).”
It was remarkable to learn all about this incredible organism that is such a key player in the rock pool environment, and one that is so close to home. As shown in the video I previously posted, they are absolutely fascinating critters, and some of the best work is currently being conducted here in the UK.
Whilst writing up my report, I greatly looked at the work of Dr Mark Briffa, an Associate Professor in Animal Behaviour at the School of Marine Science and Engineering at Plymouth University – who also starred in my last post :P
He knows a few of my lecturers here in Aber and his publications were a very interesting read. He and his colleagues focus their research on the behaviour of “shell rapping”. In this, hermit crabs fight for ownership of shells, and shell exchange may occur after a period of shell rapping, involving the initiating or attacking crab bringing its shell rapidly and repeatedly into contact with the shell of the non-initiator or defender, in a series of bouts. They found that the temporal pattern of rapping contains information about the motivation and/or relative resource holding potential (RHP) of the initiator and acts as a repeated signal of stamina.
Hermit crabs are ace! There is no denying that, and I highly recommend to anyone to further look into their incredible behaviour and physiology.
Dr. Briffa’s publications:
The Secret Life of Rock pools video:
Further info on Hermit Crabs: