P. hirsutiusculus has four large walking legs to drag it's shell and body around. It's direction is motivated by it's eye stalks, antennular flagella and antennal flagella (among other things, sensitive chemoreceptors).

This hermit crab is mostly active during the late afternoon and night, right up until dawn.

The crab may not use its chelipeds for defense, but may instead withdraw into its shell until it senses the danger has passed. The chelipeds are used primarily for fighting other hermit crabs and feeding.

Enemies of the hairy hermit crab include sea birds, fish, octopus and crabs, and other hermit crabs of the same species.

From Harbo, R. M.  1980.  Tidepool & Reef.  Hancock House, N. Vancouver, BC. 

Red rock crab: to 7 inches            

From Harbo, R. M.  1980.  Tidepool & Reef.  Hancock House, N. Vancouver, BC