wood duck, (Aix sponsa), small colourful North American perching duck (family Anatidae), a popular game bird. Once in danger of extinction from overhunting and habitat destruction, the species has been saved by diligent conservation efforts. Wood ducks nest in tree cavities up to 15 metres (50 feet) off the ground. The construction of artificial nest boxes, placed atop poles over and about bodies of water, was instrumental in halting the decline of breeding populations.
The wood duck is about 43–52 centimetres (17–20.5 inches) long. Both male and female have a characteristic head crest (absent in eclipse—or summer—plumage). The crest of the male has two longitudinal white stripes. His purple and green head, red-brown breast flecked with white, and bronze sides are readily identifiable. The distinguishing feature of the female is a white eye-ring; her body is a sooty gray-brown, with white throat and white streaked breast. An average clutch contains about 12 eggs; the ducklings hatch in about 30 days, and the next day they follow the female from the nest, jumping as far as 15 m to the ground unharmed. The ducklings eat aquatic insects and other small organisms; adult woodies prefer acorns—or other nuts, depending on habit—to other foods.