This uncommon capture of a Yellow Bittern in flight replaces the Great Egret in this Top 25 list mainly because of the degree of difficulty of the shot. It's not easy to track this fellow against a busy background of tall grasses, but the 20D + 400 5.6L's AI servo performance proved equal to the task. Wing position, good exposure and background, great bird colors and detail all came together to push this pic to my magic circle.