Check out this amazing series of photos of a grizzly bear fighting off a pack of wolves to steal their prey (a deer) in Montana's Rocky Mountains. A British photographer who was on holidays captured these images. I wonder how nervous he became when the showdown ensued.
Warning: If you aren't comfortable viewing animals being predatory, a few of these pics aren't for you.
http://www.dailymail.co.uk/news/article-4124734/Nature-red-tooth-claw-bloody-moment-bear-decides-pack-wolves-steal-deer-ve-just-killed.html