The volunteers found this morning that some feasting had been going on. After the called us to report the problem, they got rid of the crab: They removed the cage, dug down into the crab hole (they saw it in there so knew they had to get it out), and once they could see it's claw in the hole, Valerie used a new technique for removal. She found a stick and put it into the hole. When the crab grabbed onto the stick, she pulled it out. Took a couple of tries, but it worked! Then they filled the holes back in and replaced the cage. We just have to hope that crab will move on to other food sources.
Good job everyone!