Something I wonder about all the time! And now, via National Geographic, tiger "expert" Philip Nyhus has the answer:
1. “Stay calm. The tiger is probably just as surprised as you are.”Got that? Of course, if you are actually in a bathroom with a tiger, 2 and 3 are not much help. And having read 4, and gotten that image of crushed neck vertebrae in your mind, 1 is going to be a lot more difficult. So I think a combination of 5 and 6 is probably your best bet.
2. “You’d want a barrier between you and that tiger. There’s pretty much no good that comes from people and tigers coming together. If you have a door, close the door.”
3. “Distance would be important. Keep your distance. Don’t get close.”
4. “Don’t look like food: Don’t run with your back to the tiger. That may actually set off a tiger. A tiger is hard-wired from more than 10,000 years of evolution to run after small things and grab them by the neck and crush the vertebrae. So if you are facing the tiger, it is probably a good thing. Try and look big. Walk backward slowly.”
5. “Call for help. Make noise.”
6. If things aren’t going well: “Throw something at it to distract it.”