At Cabrillo Marine Aquarium, the globe crab is always on the move and doesn’t have to worry about typical crab concerns such as hiding from predators. In the wild, globe crabs aren’t as carefree and spend most of the day hiding in the sand and then under the cover of night they scurry along the sandy ocean floor scavenging for bits of decomposing plants and animals or small invertebrates.
The globe crab or Randallia ornata is very distinctive thanks to its shape and coloring. Its body is very round, hence the name globe crab, and reminds me of another member of the phylum Arthropoda…the black widow. Plus, they both have interesting patterns on their bodies.
Black widows are of course black and feature the well-known red hourglass pattern while globe crabs are white with cool purple (sometimes more red) designs on their shells. Each globe crab has a slightly different pattern making its own decorative mark on the ocean floor.
Globe crabs live close to shore to as deep as 300 feet from Baja California to as far north as California’s central coast. They don’t get very large, about two inches, but with such a unique body and style, sometimes it’s better to maintain a low profile and stay small. Being small is better for hiding during the day and out maneuvering and out running predators at night.
Go globe crabs, shake that body or scurry, whatever works best.