<Tr> <Th_colspan="2"> Synonyms </Th> </Tr> <Tr> <Td_colspan="2"> <P> Orca gladiator </P> </Td> </Tr> <P> The killer whale or orca (Orcinus orca) is a toothed whale belonging to the oceanic dolphin family, of which it is the largest member . Killer whales have a diverse diet, although individual populations often specialize in particular types of prey . Some feed exclusively on fish, while others hunt marine mammals such as seals and dolphins . They have been known to attack baleen whale calves, and even adult whales . Killer whales are apex predators, as there is no animal that preys on them . Killer whales are considered a cosmopolitan species, and can be found in each of the world's oceans in a variety of marine environments, from Arctic and Antarctic regions to tropical seas--killer whales are only absent from the Baltic and Black seas, and some areas of the Arctic Ocean . </P> <P> Killer whales are highly social; some populations are composed of matrilineal family groups (pods) which are the most stable of any animal species . Their sophisticated hunting techniques and vocal behaviours, which are often specific to a particular group and passed across generations, have been described as manifestations of animal culture . </P>

What is the diet of a killer whale
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