Wood Duck

Also known as

Acorn duck, bridal duck, Carolina duck, Carolina wood duck, squealer, summer duck, swamp duck, the bride, tree duck, wood wigeon, woody.

What is the scientific name?

Aix sponsa

• Pronounced aiks SPON-sa
• What does it mean? "Betrothed water bird." Aiks means "water bird" in Greek. Sponsa is Latin for "betrothed." This is in reference to its beautiful plumage, as though it were dressed for a wedding (Coues 1882).

Why is it called a "wood" duck?

"Wood" refers to the wood duck's habit of nesting in the cavities of trees (Terres 1980).

Where are they located?

The range of the wood duck extends from southern British Columbia down the western sides of Washington and Oregon to Southern California and from southeastern Canada to the Gulf Coast and Florida. It usually is not found in the interior portions of the United States (Palmer 1976b; Farrand 1988).

Where do they live?

The wood duck prefers sheltered waters, wooded swamps, and ponds but can also be found in open swamps or marshes. It is seldom found in salt water. The wood duck nests in the natural cavities of trees and sometimes in old nests of the pileated woodpecker. If no wooded area can be found it will nest on the ground, but this is highly unusual (Mason and Dusi 1983). It prefers a location five to 40 feet above the ground, or water, and within 200 yards of water (Palmer 1976b).

How many subspecies are there?

There are no subspecies of wood duck (Palmer 1976b).

What do they look like?

Male and females look completely different. Males have a uniquely marked head of iridescent green, blue, purple, and black with white striping ending in a mane. The eyes and eyelids are red. The throat and breast are brown with a white line separating it from the light brown sides and belly. The bill is yellow at the base, then red, white and black moving backwards towards the nostrils. The back and wings are a dark, glossy brown and the legs and feet are orange. These colors are brighter and most intense during the breeding season.Females are unspectacular in comparison, lacking the coloration and long mane of the male. However, they have a distinctive teardrop shaped white patch around the eye, tapering towards the back of the head. The head and neck are gray-brown, the body is dark brown above and light brown below. Sometimes females can develop the male's colorations as a result of gonadal malfunction (Palmer 1976b).

How big are they?

Males are between 17 and 21 inches in length and females are between 17 and 20 inches (Hester and Dermid 1973). The wingspread is slightly more than 28 inches in both sexes (Hester and Dermid 1973). Males and females weigh between 1 and 2 pounds, females are usually lighter (Belrose 1976).

How long do they live?

One wood duck lived 17 years, 7 months (Clapp 1982) and another 22 years, 6 months (Klimkiewicz and Futcher 1989). A study estimated the annual mortality rate at 77% for newborns. The average life expectancy for wood ducks is 1.2 years (Belrose 1976).

How fast can they fly?

The fastest speed recorded in one study was 55 miles per hour; the slowest 39 miles per hour. The average flight speed has been measured as 47.1 miles per hour (Lokemoen 1967).

What do they eat?

Ninety percent of the wood duck's diet is plant matter and 10% is animal matter, consisting mostly of insects. Aquatic plants such as wild rice, pond weed, and wild celery make up the bulk of its diet. Wood ducks eat more fruits and nuts than any other American duck, particularly acorns (Hester and Dermid 1973). One study found 56 acorns in a wood duck's crop (a storage place in some bird's necks) and stomach (Jarosz 1960).

Interesting notes: The female wood duck has the unusual habit of laying some of her eggs in other wood ducks' nests, leaving the raising of the nestlings to another female. Called "brood parasitism" or "dump nesting," one study showed that over 50% of wood duck nests may contain eggs from more than one wood duck (Semel and Sherman 1986). Some nests have been reported to contain eggs from as many as four or five different wood ducks (Belrose 1976). What would cause this behavior? The most obvious answer is that the female is then relieved of child-rearing duties, however, this doesn't explain why a female that has dumped some of her eggs in another wood duck's nest will still make her own nest and raise young.

A currently accepted theory, for all animal behavior, is that each animal is driven by the need to leave offspring. In contrast to the old, and no longer accepted, idea of "survival of the species," most animals act in ways that will insure their offspring's survival. If the female wood duck leaves some of her eggs in another wood duck's nest and also raises her own, she increases her chances of leaving more offspring (Davies 1991).

Although the wood duck was once abundant throughout the United States, forestry practices and development almost caused the wood duck to go extinct around the turn of the century. Protection of this species has since allowed it to make a comeback, but not throughout its entire historical range (Ehrlich et al 1988).