Pacific Rock Crab

Pacific Rock Crab (Romaleon antennarium)

Contributed by TPERP Art Geisler


Where to find them: The Pacific Rock Crab lives in the low tide zone in rocky crevices. You can find them along the Pacific Coast of North America, from San Francisco, California to Baja California, Mexico.

What do they eat: They feed by scavenging and predation. They feed on bivalves, snails, echindoerms and crustaceans, usch as hermit crabs.

Who eats them: Otters, sharks, sea bass and octopus.

Adaptations: The Pacific Rock Crab can grow up to 5 inches (13 cm) wide and 3.5 inches (9 cm) long. The crab’s shell can be yellow, red, and orange in color. Their claws have distinctive black tips.

Reproduction: Mating occurs in the spring and fall, after the female molts. Eggs are extruded 7-8 weeks after mating. These eggs are an orange-colored mass.

What’s their life like: Few studies have been done. From a few catch and release studies, the crab rarely travels more than a few kilometers from where it was released.

Interesting facts: It is fished both commercially and recreationally since it has been reported to have a taste similar to that of the Dungeness crab. They have been overfished. These crabs are also loving and entertaining companions in aquariums.



Phylum: Arthropoda
Class: Malacostraca
Order: Decapoda
Family: Cancridae
Scientific Name: Romaleon antennarium
Common Name(s): Kelp Snail

Source(s) of Information:


Last revised 09-Jan-18