They are nocturnal crabs which means they only come out at night. They can dig very quickly in the sand. In the morning, before the beach is cleaned, you can see round holes in the sand where they have burrowed. A crab grows by molting, or shedding its hard shell, and growing a newer, bigger one. It is believed that ships traveling from Japan, Korea or other Asian countries accidentally brought the Japanese shore crab to the New Jersey coast.
Crabs eat almost anything.
No, the horseshoe crab is not considered a crab. It's closest living relative is actually a spider. Now here are the answers to the Picture Quiz. This is a Spider crab. Its body or carapace is brownish and is about four inches long.