Hermit Crabs are nocturnal

Four years into crabbing and I am still discovering new crab owners who have been told that hermit crabs are exclusively nocturnal. This has been disproven in several crabbing communities and in scientific research yet this myth continues to circulate as fact. What will it take to get rid of this bunk once and for all?

Mid day in my tank:


  1. Many of my crabs sleep during the day but they are definitely not exclusively active at night. Research documents have shown that hermit crabs will forage for food during the day. At peak hours they are likely to seek shelter but in the morning hours and afternoon hours they are scavenging. I always have crabs up moving about in my tank during the day. It has been that way since I installed my overhead lights. The myth I am talking about is that hermit crabs are ONLY active at night, which is what most pet stores tell people.

  2. I have 3 crabs that are out all day and 3 that come out only at night, I feel they are not nocturnal just depends on the crab and the crabs personality. My most out going crabs are out all day and all night and my shy crabs are out only at night after I go to bed.

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