I have never tried it but I know young alligators eat crayfish in the wild and in captivity. I don't know if the crab's exoskeleton is much harder but I would imagine it would be alright. I think alligators would be equally adapted to eating crabs. I know when I feed crustaceans to my turtles that they tend to pass the bits of shells without much problem. Maybe its the same with gators.
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