 Before we go any further into the dangers that they faced, what exactly is a beluga? So a killer whale, also known as an orca, is the huge black and white one. People might recognize these guys from the film Free Willy. And then belugas, they're light gray or kind of white, and they have a bulbous, melon-like head. They're one of the smallest species of the whale, and they're native in the Arctic.