LIMPETS: Long-term Monitoring Program and Experiential Training for Students

Hermit Crabs(Pagurus spp.)

Description:

Rocky intertidal hermit crabs in California are represented by the family Paguridae. They live in the abandoned shells of snails to protect their soft abdomens. Carapace grows to approximately 2 cm in length. P. hirsutiusculus, abundant in the mid zone, has white bands on walking legs, dark antennae with fine white bands, and a dark orange-brown body. P. samuelis is the most abundant hermit crab in the high zone of central and southern California. It has a hairy carapace and legs, blue bands on walking legs, and red antennae.

Distribution:

Varies with species.

Habitat:

Common in tidepools on rocky shores; P. hirsutiusculus is usually found in the mid to low intertidal; P. samuelis is typically found in the high to mid intertidal but also subtidally in giant kelp holdfasts.

Diet:

Important scavengers of dead plant and animal matter.

Fun Fact:

Hermit crabs can be choosey about the shells they live in. P. hirsutiusculus prefers the shells of olive snails while P. samuelis prefers the shells of turban snails.

Reason for Monitoring:

Important scavengers of dead plant and animal matter. Sensitive to pollution. Fun to count.

References:

Morris, R.H., D.P. Abbott, and E.C. Haderlie. 1980. Intertidal Invertebrates of California. Stanford University Press, Stanford, California.