The bull shark 's diet consists mainly of bony fish and sharks , including other bull sharks , but can also include turtles , birds , dolphins , terrestrial mammals , crustaceans , echinoderms , and stingrays .
Bull sharks are also been known to feed on sea turtles , dolphins , crabs , shrimp , sea birds , squid , terrestrial mammals , echinoderms , and crustaceans .