Wood Ducks thrive in bottomland forests, swamps, freshwater marshes, and beaver ponds. They are also common along streams of all sizes, from creeks to rivers, and the sheer extent of these make them an important habitat. Wood Ducks seem to fare best when open water alternates with 50–75% vegetative cover that the ducks can hide and forage in. This cover can consist of downed trees, shrubs such as alder, willow, and buttonbush, as well as emergent herbaceous plants such as arrowhead and smartweeds.Back to top
Wood Ducks eat seeds, fruits, insects and other arthropods. When aquatic foods are unavailable they may take to dry land to eat acorns and other nuts from forests and grain from fields. Diet studies indicate a lot of variability, but plant materials make up 80% or more of what the species eats. Examples of food eaten include acorns, soybeans, smartweed, water primrose, panic grass, duckweed, millet, waterlily, blackberries and wild cherries, as well as flies, beetles, caterpillars, isopods, and snails.Back to top
Breeding pairs search for nest cavities during early morning. The male stands outside as the female enters and examines the site. They typically choose a tree more than 1 foot and often 2 feet in diameter, with a cavity anywhere from 2–60 feet high (higher sites seem to be preferred). These cavities are typically places where a branch has broken off and the tree's heartwood has subsequently rotted. Woodpecker cavities are used less frequently. Wood Ducks cannot make their own cavities. The nest tree is normally situated near to or over water, though Wood Ducks will use cavities up to 1.2 miles from water.
Nest cavities can have openings as small as 4 inches across, and these may be preferred because they are harder for predators to enter. Wood Ducks sometimes use much larger openings, up to a couple of feet across. Cavity depths are variable; they average about 2 feet deep but in rotten trees can be 15 feet deep (the young use their clawed feet to climb out). Nest boxes of many designs have proved very popular and successful with Wood Ducks, though plastic nest boxes can overheat in strong sun. The female lines the nest with down feathers she takes from her breast.
|Clutch Size:||6-16 eggs|
|Number of Broods:||1-2 broods|
|Egg Length:||1.8-2.4 in (4.6-6.1 cm)|
|Egg Width:||1.4-1.6 in (3.5-4.2 cm)|
|Incubation Period:||28-37 days|
|Nestling Period:||56-70 days|
|Egg Description:||Glossy creamy white to tan.|
|Condition at Hatching:||Chicks hatch alert and with a full coat of down. A day after hatching they leave the nest by jumping out of the entrance.|
Wood Ducks feed by dabbling or short, shallow dives. They are strong fliers and can reach speeds of 30 mph. Wood Ducks are not territorial, with the exception that a male may fight off other males that approach his mate too closely. Courting males swim before a female with wings and tail elevated, sometimes tilting the head backwards for a few seconds. Males may also perform ritualized drinking, preening, and shaking movements. Both members of a pair may preen each other. Egg-dumping, or "intraspecific brood parasitism" is common in Wood Ducks—females visit other Wood Duck cavities, lay eggs in them, and leave them to be raised by the other female. This may have been made more common by the abundance and conspicuousness of artificial nest boxes; in some areas it happens in more than half of all nests. Individual females typically lay 10-11 eggs per clutch, but some very full nests have been found containing 29 eggs, the result of egg-dumping.Back to top
Wood Ducks are found throughout the year in the U.S. and populations increased between 1966 and 2019, according to the North American Breeding Bird Survey. Partners in Flight estimates the global breeding population at 4.6 million and rates them 7 out of 20 on the Continental Concern Score, indicating a species of low conservation concern. This is good news, considering their dramatic declines from hunting in the late 19th century. Even so, Wood Ducks are second only to Mallards in the number of ducks shot by hunters every year. As cavity nesting birds, they rely on dead trees which are often in short supply. Providing predator-resistant nest boxes near ponds has a positive effect on population growth.Back to top
Hepp, Gary R. and Frank C. Bellrose. (2013). Wood Duck (Aix sponsa), version 2.0. In The Birds of North America (P. G. Rodewald, editor). Cornell Lab of Ornithology, Ithaca, New York, USA.
Lutmerding, J. A. and A. S. Love. (2020). Longevity records of North American birds. Version 2020. Patuxent Wildlife Research Center, Bird Banding Laboratory 2020.
Partners in Flight. (2020). Avian Conservation Assessment Database, version 2020.
Sauer, J. R., D. K. Niven, J. E. Hines, D. J. Ziolkowski Jr., K. L. Pardieck, J. E. Fallon, and W. A. Link (2019). The North American Breeding Bird Survey, Results and Analysis 1966–2019. Version 2.07.2019. USGS Patuxent Wildlife Research Center, Laurel, MD, USA.
Sibley, D. A. (2014). The Sibley Guide to Birds, second edition. Alfred A. Knopf, New York, NY, USA.