Orcas are called killer whales due to the fact that they are the top predator in the ocean. They are the hunters, not the hunted. They eat almost anything and everything they â¦ can find including other whales.n 1971, Sea World aquarium in San Diego Ca. got a killer whale, which they named Shamu. In order that the general public would not know how long killer whales live in captivity (which isn't as long as they live in the wild), Sea World names most of their killer whales Shamu.