On this day, several birds were amicably sharing at the feeder. But two Pine Siskins took an immediate disliking to one another. For a while they pecked and darted at each other. Finally both went airborne in full attack mode. Photo taken with a Nikon D700, a Sigma 50-500mm lens at f5.6 with exposure of 1/6400. The focal length was 175mm and the ISO set at 1250. David Barfield