Residents of tropical areas know the clickety-clack sounds of hermit crabs waking up and moving about at night. These shell creatures use their legs and claws to walk, climb, burrow and switch shells. Since they're most active at night, you'll need to observe your hermit crabs after dark.
Hermit crabs use their legs to walk. Unlike other crabs, their legs bend forward and back instead of from side to side. They walk forward and back using their legs, holding their abdomen up. Hermit crabs with heavy, large shells may drag their bellies across the sand as they walk.
Hermit crabs enjoy climbing and burrowing into sand. Provide your hermie with branches and rocks in his cage to promote climbing behavior. Crabs may be more likely to climb and dig at night, when they are most active. Climbing objects can provide crabs with places to hide, which can make them feel more secure.
As hermit crabs grow, they occasionally need to move into larger shells. Provide your pet hermit crabs with various empty shells so they can switch. In the wild, hermit crabs sniff out deceased crabs. They may hoist the dead neighbor out of its shell in exchange for a better-fitting shell. Such occasions often become large shell-swap parties where crabs can trade shells for one that fits better. To switch, crabs hold onto the new shell and current shell with their claws, clambering quickly from the old shell to the new shell.
There are times when hermit crabs appear not to be moving. When getting ready to molt, crabs tend to remain still. During the molting process, which can take several weeks, crabs sit in one spot. Hermit crabs are nocturnal creatures, so they may move little during the day. When tank water gets too cold, crabs will also remain still. Keep the water between 70 and 80 degrees Fahrenheit.
- Hermit Crabs: Everything About Anatomy, Ecology, Purchasing, Feeding, Housing, Behavior, and Illness; Sue Fox
- University of North Carolina: Hermit Crab
- The Journal of Experimental Biology: Locomotion of Hermit Crabs (Coenobita Compressus) on Beach and Treadmill
- hermit crab image by Snowshill from Fotolia.com