Fossil evidence indicates that `` C. megalodon '' preyed upon cetaceans ( i.e. , dolphins ) , small whales , ( including cetotherrids , squalodontids , and `` Odobenocetops '' ) , and large whales , ( including sperm whales , bowhead whales , and rorquals ) , pinnipeds , porpoises , sirenians , and giant sea turtles .
Fossil evidence is that `` C. megalodon '' preyed on cetaceans ( i.e. , dolphins , small whales , and `` Odobenocetops '' , and large whales , ( including sperm whales , bowhead whales , and rorquals pinnipeds , porpoises , sirenians , and giant sea turtles .