As its name implies, this crustacean is often found in and around rocky places and features reddish-purple coloration.
It can grow to more than 10 inches across, but 4 to 6 inches is more common. Its large claws are tipped in black and they have a wide, fan-shaped body.
This cool creature crushes barnacles with its large pincers and eats them. It also eats smaller crabs, sea cucumbers, and many other intertidal invertebrates, as well as dead fish.
While searching tidepools, I saw this “shell” move. It didn’t take long to realize that it was not a shell at all, but rather a juvenile Red Rock Crab, which can be white with a pattern of dark lines.
I enjoy finding these hard-shelled creatures, whose other common names include Red Crab, Cancer Crab and Red Cancer Crab.