These are male Northern Flickers. They put on quite a show for 20 minutes or so. At first we all thought it was a male and female doing a courting ritual, then someone said, wait a minute, these are both males, what's going on here? We think this was some kind of territorial display. They would stare at each other a bit, then crane their necks at each other for a few seconds, then stare again. Really needed a video camera to adequately capture the action.