The only recorded deaths of humans caused by Orcas have been during captivity (perhaps 3 ?). That tells me that they are smart enough to let us alone or not leave any witnesses, unless they have nothing to lose.
"I had job before this, I had a job before this. Ultimately, it was that job that drove me into this. I worked at an aquarium, an aquarium with lots of money from the government so it was HUUUGGEE! I uh I was a clean n' scrub man we called each other in the C n' S union. I scrubbed the inside of the killer whale tank. The, and after a while the boys in the C n' S or clean n' scrub we just sort of made it one word: the killer whale tank, the killer whale tank uh, the killer whale tank uh. I'm going into the killer whale tank UH yeah. I got along with these two big beasts so well, it was like they knew me they looked at me with their hundred year old eyes and it was like they knew me. High, I'd put on my SCUBA gear, my mask, my regulator, {breath} and I'd fall into the tank with nary a sound maybe a pfftt. And then I was underwater. Sometimes, I'd jump out, right in front of the window when people are expecting a killer whale and they see a human, they get spooked. Spooked. Anyway I'd do that. But I was in the water this particular day, unbeknownst to me, Shamu and Bartholomew, their relationship had grown stale, seems I was going in there so much and looking so good, Shamu took a shining to me, and they're so smart those things ya know they've got all these human emotions, love, lust, GREED, hundred year old eye jealousy. Bartholomew was LIVID. Unbeknownst to me I can't hear a goddamn thing underwater. He came up he was bumping up against me a lot. The stale, killerwhale, bumping up against someone so pale and frail. How was I to know the killerwhale whose relationship had gone stale, well, he brushes up against me sometimes, skin's like sandpaper I say "Hey man, Bartholomew what's up? What's up? What's going on big fella? What is it? What is it? I, I don't wanna steal your mommy, and I sure don't want to take the place of your daddy, I only want to be your friend." And he circled around and I thought we were all patched up and I was scrubbing and he took my- he came up, he came up, he came up, he ripped my left arm off. I mean the killer whale they're beasts of the deep they're I mean they're quite docile and friendly in captivity but somewhere along the line, the thousands of years of breeding just snapped and he took my left arm, man he took my left arm, took my friggin' left arm. "Wha-What is it Bartholomew?" I spoke to him in a language he could understand, as I came back."
-Gord Downie, sang in the middle of
New Orleans is Sinking randomly at one concert.
and 2 
although do not quote me on the 
