Walking back to my car after visiting Johnson Space Center this summer, a group of ducks started stalking my friend and I. Thinking we had food I suppose, they intercepted our path and wouldn't let us advance until we presented them with something. When I pulled out my camera, this one brave duck advanced while the others retreated in disappointment. This guy stood around as if to say, okay take your best shot, then I've got to run. He was patient though while I fumbled with my settings longer than I should have and allowed me a few shots. Then he was off with his friends, seeking out some other potential contributor.