As we were walking we approached a fallen tree along the side of the trail, with a huge pile of roots sticking up in the air. Guthook was in the front, I was directly behind him, and @mypictograph was bringing up the rear. As Guthook got closer to the tree I heard him holler, jumping back in surprise, as he was kamikaze'd by an angry bird shooting out of the roots. Apparently this trail doesn't see much use, as the bird had assumed that hip-hight along the edge of the path was a safe place to build a nest.