Several wood duck nest box plans, including the type of timber, size of the panels and size of the entry hole required are posted on sites like Ducks Unlimited, WikiHow and the Wood Duck Society. Cedar wood is the recommended construction material. The dimensions are variable, but boxes are usually about 9.25 inches wide by 31 inches high by 14 inches deep. The entrance hole is cut to about three inches high by four inches wide.
Pre-made wood duck nest boxes are also available online or through various waterfowl hunting and conservation groups. Nest boxes should be placed on posts or tree trunks on or near water. Place the box about five to six feet above the ground. A predator guard on the pole or tree is highly recommended. Though the dimensions of the hole may appear too small for a duck, they can squeeze through with little problem. Be sure not to make the hole too big as it can invite predators to steal eggs or ducklings.
Wood duck females lay about a dozen eggs that hatch in 28 to 32 days. Ducklings stay in the nest for the first day or two after hatching. Afterwards, the mother duck will leave the box and begin to call for them. The ducklings will jump out of the box and follow their mother's voice until they find her and a water source.