Nest box specification

Wood Duck house dimensions

The Wood Duck nests in tree cavity or nest box over or near water A box built to its measurements — and no bigger — is what makes it choose yours.

Ducks and geese (Anatidae)Wood DuckAix sponsa

The specifications

Entrance hole: 4 × 3 in oval
Floor (inside): 10 × 18 in
Mounting height: 6–20 ft
Bird size: 18.5–21.3 in, 16–30.4 oz
Clutch: 6–16 eggs
Incubation: 28–37 days
Time in nest: Ducklings leave within 24 hours
Broods: 1–2 per season

Build and mounting checklist

Drill the entrance to exactly 4 × 3 in oval — oversized holes let in European Starlings and larger predators.
No outside perch: cavity nesters don't need one, and it helps House Sparrows and predators.
Unpainted interior, 3/4-inch untreated wood (cedar or pine) or poly-lumber for insulation.
Drainage holes in the floor corners and ventilation gaps under the roof.
A side or front panel that opens so you can monitor and clean the box.
Rough or grooved inner front wall so nestlings can climb out.
Pole mount with a stovepipe or cone baffle to stop snakes, raccoons and cats.

When to put up a Wood Duck box, by state

Boxes should be up and clean a month before local nesting starts. Dates shift with latitude:

Place	Up by	Nesting	Clean out
Alabama	January	February–June	July
California	January	February–June	July
Florida	January	February–June	July
Georgia	January	February–June	July
Louisiana	January	February–June	July
Mississippi	January	February–June	July
South Carolina	January	February–June	July
Texas	January	February–June	July
Arkansas	February	March–June	July
Connecticut	February	March–June	July
Delaware	February	March–June	July
Illinois	February	March–June	July
Indiana	February	March–June	July
Iowa	February	March–June	July
Kansas	February	March–June	July
Kentucky	February	March–June	July
Maryland	February	March–June	July
Massachusetts	February	March–June	July
Michigan	February	March–June	July
Missouri	February	March–June	July
Nebraska	February	March–June	July
New Jersey	February	March–June	July
New York	February	March–June	July
North Carolina	February	March–June	July
Ohio	February	March–June	July
Oklahoma	February	March–June	July
Oregon	February	March–June	July
Pennsylvania	February	March–June	July
Rhode Island	February	March–June	July
South Dakota	February	March–June	July
Tennessee	February	March–June	July
Virginia	February	March–June	July
Washington	February	March–June	July
West Virginia	February	March–June	July
British Columbia	March	April–June	July
Maine	March	April–June	July
Manitoba	March	April–June	July
Minnesota	March	April–June	July
New Brunswick	March	April–June	July
New Hampshire	March	April–June	July
North Dakota	March	April–June	July
Ontario	March	April–June	July
Quebec	March	April–June	July
Saskatchewan	March	April–June	July
Vermont	March	April–June	July
Wisconsin	March	April–June	July

Full Wood Duck species guide →

Frequently asked

What size hole does a Wood Duck need?

4 × 3 in oval. A hole cut to this size admits the Wood Duck (18.5–21.3 in) while keeping out larger competitors.

How big should a Wood Duck house be inside?

A floor of 10 × 18 in. The Wood Duck lays 6–16 eggs, so the floor has to hold the full clutch plus growing nestlings.

How high should I mount a Wood Duck box?

6–20 ft. Mount on a pole with a predator baffle where possible rather than a tree or fence.

How long does a Wood Duck use the box?

Incubation takes 28–37 days and the young stay in the nest Ducklings leave within 24 hours. Broods per year: 1–2 per season.

Sources

Timing reflects typical patterns for the region as a whole; local dates vary with elevation and year. Check the linked eBird bar charts for your county.