INTRODUCTION 

The hairy hermit crab Pagurus hirsutiusculus ("Pah GURR us her suit ee US cue lus") is one of several common "hermits" in the rocky intertidal.   Hermit crabs are fascinating creatures. Like other crabs they have an exoskeleton which must be molted regularly to allow growth and like all crabs they are decapods, or ten legged, including the two claws.

One attribute of hermit crabs that sets them apart from other kinds of crabs is their soft abdomen.  In most species the abdomen is coiled in the same direction as typical snail shells and has specialized pads to hold it tightly in a snail shell.  Don’t try to pull a hermit from it’s home- it will only result in injury or death to the crab.

Look carefully in tide pools the next time you are at the beach, or viewing the aquaria at the Marine Ecology Centre. Chances are you will see what looks like walking snails- these are hermit crabs!

P. hirsutiusculus is known as the hairy hermit crab due to the small hairs that cover the legs and thorax. It usually has orange antennae and is fairly easy to identify due to the white bands on it’s walking legs.

Like many other hermit crabs the hairy hermit crab’s right cheliped is much larger than the one on the left. This large claw is used as a door to it’s shell as well as a weapon and food shredder. It is also equipped with a set of muscles which enable it to jerk quickly back into the safety of it’s shell if danger threatens. The hairy hermit crab’s abdomen, like that of all other hermits, is flexed to the right to fit the coiled shape of the shells it inhabits.

Photo by Iris Churcher,

Malaspina University-College

The Hairy Hermit Crab

Jensen