Mole Crab (Emerita analoga)
Mole crab (photo credit: Lisa Habecker)
Mole crab with eggs (orange), next to a sea gooseberry (photo credit: Susan Glarum)
Description: Pacific mole crabs, or sand crabs, don’t look like typical crabs, they have an unusual shaped carapace. They are typically up to 3.5 cm long and look like a sandy gray oval with flat legs and fuzzy antenna. They use their claw-less legs to bury themselves in the sand with just their antennas above ground.
Habitat: Mole crabs range from Alaska all the way to Chile or Argentina! They are, however, less common north of Oregon. They are found on sandy beaches and prefer to be buried in sand right in the waterline. In Cannon Beach they can be seen along the entire length of the beach, but especially around the edges of tide pools.
Diet: While buried in the sand, mole crabs use their antennae to filter feed, primarily on plankton and detritus.
Tide Pool Tidbits:
Mole crabs are the only crabs that walk backwards and even swim and dig themselves into the sand backwards!
In the summer it is common to see females with thousands of bright orange eggs attached to their undersides.
References: Coastal Interpretive Center, Walla Walla University