Pair bonding is behavior similar to courtship and mating behavior, only it may be performed outside the breeding season. Here a pair of wood ducks prepare for the southward winter migration they will make together by solidifying their relationship through mutual preening.
Moments before I took this image, several photographers left the scene because clouds obscured the direct sunlight we had been shooting in. One fellow commented that the good light was gone, and the band of them packed it in. One other photographer and I stayed and were rewarded with these tender displays of public affection. Sweet light eh?