The wood duck, Aix sponsa, breeds in scattered areas across the United States, southern Canada, and Cuba. Northern populations migrate south for the winter, and major wintering areas include California and the southern United States. The species occurs year-round in Utah, although it is more common in the state during winter. Wood ducks prefer marshes and ponds near woodlands, and are especially fond of flooded forests.
The wood duck is a cavity nester that typically nests in hollow trees or man-made nest boxes; nests are almost always near water. Nine to fifteen eggs are laid and incubated for about one month by the female alone. Wood ducks often lay their eggs in the nests of other females, so some nests may contain thirty or more eggs. Young are able to fly at about nine weeks of age. Wood ducks eat primarily plant material during the winter, and insects during the spring and summer.
During the mid-1900s, wood duck populations were much reduced from current levels. Fortunately, habitat improvements and better wildlife management practices have allowed the species to make a rapid recovery.