Hermit crabs are crustaceans, i.e., they are related to crabs, lobsters and prawns. However, unlike other crab species, hermit crabs do not have their own carapace or shell. Hermit crabs have a soft, vulnerable abdomen and occupy empty seashells to protect themselves and from which they derive their name ‘hermit’. They are usually a reddish-orange colour.
The hermit crab will crawl around with the shell on its back and will only leave when it grows too big, and has to find a new, larger shell, such as that of the common whelk. In most cases, they will use the shells of dead snails, but squabbles for possession of an already occupied shell frequently occur. In addition to finding a new ‘home’, hermit crabs also moult. When ready to moult, the new skeleton grows under the old one. The old exo-skeleton splits and comes off; the new skeleton takes some time to harden.
One of the most fascinating aspects of hermit crab behaviour is their association with other animals. Acorn barnacles, or algae can be found growing on their shells and they can enjoy symbiotic (mutually beneficial) relationships with sea anemones. The anemones’ stinging tentacles help to deter predators and provide amazing camouflage. In return, the sea anemone gets scraps from the Hermit Crab’s meals and is transported to food sources. Some hermit crabs even transfer their anemones when they ‘move’ from a smaller shell into a larger shell. The hermit crab is a scavenger and will look for dead and dying forms of marine life to feed on.
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This piece was prepared online by Panuruji Kenta, Publisher, SEVENSEAS Media