The spiny dogfish usually feeds in groups. They feed mainly on pelagic fish such as herring, menhaden, capelin, sand lance, and mackerel, often consuming large numbers of them. They have been known to bite through fishing nets to be able to feed on the caught fish, usually releasing most of the fish. This has given the dogfish a bad reputation among fishermen. Other food items of this species includes molluscs (such as squid and octopus), crustacea (such as shrimp and crab), jellyfish, sea cucumber, algae, smaller sharks, and shark egg cases.