We got unintentionally surrounded by these enormous bison in Grasslands National Park, Saskatchewan. They tell you to stay far enough away that you can cover them with your thumb held out at arms length and that is how it started out, I swear. The thing is, they don't tell the bison that and when you're looking through a telephoto lens, you can kind of lose track of what's going on around you. You know how, when you're watching an old zombie movie, you think "what's so scary about them? They're so SLOW", but the thing is that they're also steady and sooner or later you trip and fall and they're up on you? That's what bison are like, just constantly creeping imperceptibly forward until suddenly you look up and realize they are all around you and actually very close. Thankfully, we had not walked away from the car, but I have to tell you that the Toyota Echo hatchback did not feel especially secure at that moment in time. Or the next moment, when several of the large males began humping nearby fence posts and I was quite convinced that North America's largest land mammal was going to mount one of North America's tiniest cars at any minute. This fellow did not like me pointing the big lens at him AT ALL and this photo was taken as I rapidly wound up the window (because THAT would offer so much protection).