Hermit Crabs

Instead of growing a natural shell of its own, the recluse crab makes utilize of a used shell for protection.  It often shares this “home” with other animals such as sea anemones, barnacles, and worms.

Hermit crabs are scavengers on the seashore and seabed. They contrast from the true crabs on account of they make a point not to have a fifth pair of walking legs. Their fourth pair of legs is very small and can be seen only when the animal is removed from its snail shell home. This pair of legs grips the inside of the shell and holds the animal in place.

The abdomen is not folded under the front of the body as it is in the true crabs. Instead it is long and twisted to the right so that it fits into the snail shell easily. The abdomen is also soft, so the protection given by the snail shell is very important.

Moving Home

A hermit crab outside its snail shell is vulnerable to predators, so moving house is a dangerous time. A growing hermit soon finds its shell is too small and goes in search of a new one, which it finds simply by looking. Having carefully checked out the new shell, it must move in quickly before another hermit grabs the shell or a predator spots the crab.