This long-clawed hermit crab is inhabiting a periwinkle shell.
This long-clawed hermit crab is inhabiting a periwinkle shell.
E. Zabel, courtesy of URI

Hermit Crabs
Broad-clawed Hermit Crab (Pagurus pollicaris),
Long-clawed Hermit Crab (Pagurus longicarpus)

Color: Long-clawed hermit crabs have reddish tan bodies, and their claws are long, thin, and white with a grey or brown median stripe. Broad-clawed hermit crabs are reddish, grey, or tan with flattened, broad claws.
Size: Long-clawed hermit crabs grow up to 1 1/2 inches long. Broad-clawed hermit crabs grow up to 4 inches long.
Habitat: Rocky tidal zones, tidal pools, salt marshes, and open shores.
Seasonal appearance: All year.

Description

Two of the most common species of hermit crabs in Rhode Island are the broad-clawed and the long-clawed hermit crabs. They can be distinguished from each other by the shape of their claws and their size. Long-clawed hermit crabs are the smallest species and inhabit vacant common periwinkle and oyster drill shells. Their major claw is narrow and usually hairless. The broad-clawed hermit crab is the largest hermit crab in Rhode Island. It has a broad, flat major claw and resides in large shells of moon snails or whelks.

Life History and Behavior

Hermit crabs earn their name because they live in mollusk shells, and they have a tendency to withdraw into their shells when they are threatened. These shells protect the hermit crab's soft, curved abdomen. The crab's tail clamps onto the shell and it supports the shell using a few of its walking legs. This enables the crab to orient the shell maintain its position within the shell. When a hermit crab outgrows its current shell, it will select a new one to inhabit.

Long-clawed hermit crabs live mostly in shallow water and are common in tide pools and salt marshes. Broad-clawed hermit crabs live in deeper waters. Hermit crabs are active animals, moving about in search of food. They are omnivorous and feed on small bits of fish, grass shrimp, dead plants, algae, and other hermit crabs.

Special Notes


Adapted from The Uncommon Guide to Common Life on Narragansett Bay. Save The Bay, 1998.