Although I'm not familiar with the responses all true crabs have to cold temperatures, I've never heard of any that hibernate. My guess is the same, that the sluggishness is just a sign of lowered metabolism due to that species' reaction to the temperature (since not all Crustaceans will slow down that much when put in a fridge). I've been told that it's a common tactic among fishermen who use certain true crabs as bait: throw them in a shallow tub, flop a wet cloth over them to keep them from drying out, and put them on the bottom shelf of the fridge. When cold, they are easy to manage and don't escape/kill each other/etc. From videos I've seen of that practice, they don't completely shut down and will still mill around under the cloth a bit.
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do you eat them straight from the machine or what 
