mine used to eat shrimp ooohhhh and they can eat your fishes . they can b nasty fellows they move very fast .mussel etc .
that was my one till i pull him out and left him on the lawn .after he kill one off me fishes .I have tow more that i have been trying to catch and will make compost lol.
have found 2 little six legged ones that i will leave alone .flat starfish not the b/star