when i feed iorek fresh mackerel he gets everything, head, tail, backbone, all of it i could never cut it up and do anything with it since i really don't like fish! i just take it from the freezer and then drop it on the floor and he loves it. i feed the fish mostly frozen since i also hate the smell of fish. iorek doesn't mind he loves fish days. he always eats the "middle" out of the fish first. someone on here suggested that might be because that is where the organs are.