Killer Whale / Despite its name, the killer whale (aka the orca) is classified as a dolphin, not a whale (tho all dolphins fall under the 'toothed whale' suborder of Odontoceti). In fact, it is the largest of all dolphin species. They hunt in pods, with a widely varied diet that includes fish, squid, birds, seals, sea lions and even whales. Animals Found in Antarctica.