Has a Killer Whale ever killed a human.?
There is no account on record of a killer whale killing a human in wild or one that is a “show” whale. There have been cases of the show whales grabbing someone and taking them underwater, and scaring them close to death. But upon examination, the individuals that were “grabbed” were wearing bright colors, just like the toys and instruments used to train the whales, so they believe that they were just mistaken for another toy. That is one reason you will see trainers usually in simple black wet suits. But there has been no case of a wild killer whale attacking and killing a human in the way a shark has done. Not that you want to press your luck if you are in an area where they are.
