They eat crabs, lobsters, and other shellfish.
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What eats octopus?
Whales eat octopus [sperm whales have giant octopus as a favorite food]. Octopus eat each other octopus. Humans eat octopus. Anything that can catch an octopus (that isn't easy) will eat it. Killer whales [or Orcas, a kind of toothed whale] eat octopuses. ...