The wood duck is one of only a few waterfowl species that call Georgia home year-round. (Photo: USFWS)
Wood ducks are commonly seen in Georgia’s freshwater and tidewater marshes, inland and coastal swamps, and other wetland areas. The wood duck is perceived by many to be one of the most beautiful waterfowl species in North America and is a perennial favorite of area waterfowl hunters. Fortunately for the residents of Georgia, the wood duck can also do something that most duck species cannot. These colorful, attractive birds call Georgia home.
The wood duck is one of the few waterfowl species found throughout the year all across the state. Because of this, Georgia landowners can have a greater impact on wood ducks than on other waterfowl species that may only spend the winter months in the area, or just simply pass through on their way north or south.
“There are many factors to consider when managing a property for wood ducks,” said wildlife biologist Justin Brock. “The ducks need an environment that provides the right amounts of food, cover, and water to survive. When considering all the factors, however, the amount of quality nesting cavities is sometimes overlooked.”
The wood duck’s preferred natural nesting site is traditionally a hollow or cavity inside a mature tree. According to Brock, in many areas there are not adequate numbers of age-appropriate trees due to logging or other activities to provide natural nest cavities. In such areas the construction of wood duck boxes can often be a welcomed and needed management strategy.
“The U.S. Fish and Wildlife Service first used wood duck boxes in 1937,” Brock said. “Since that time they have been used on numerous properties to increase local populations of wood ducks. Boxes should be placed in any habitat that has enough food and cover, but does not provide enough natural nesting cavities. Once an area has been identified, the number of boxes needed and the location of each box must be determined.”
Brock advises starting small when first putting wood duck boxes in an area.
“Place only the number of boxes that can be maintained annually,” he said. “The recommended number of boxes is one per acre of suitable habitat, with the boxes spaced at least 55 to 110 yards apart. Once 50-80 percent of these boxes are being used, more may be added if they can be properly maintained.”
Opinions differ on how much to conceal or isolate the boxes. Research shows that wood duck boxes placed in areas that are thickly concealed with dense vegetation are less susceptible to becoming a “dump nest” (nests where multiple ducks lay eggs and cause the nest to be abandoned). However, nests located in open areas tend to be more productive despite their dump-nest attractiveness. Therefore, all factors considered, it is recommended boxes be placed in the open and observed frequently to determine their degree of consistent nesting success.
“Ideally, nest boxes should be placed over or very close to water,” Brock explained. “However, they do not have to be over water if it makes them too hard to maintain. It’s important to remember, though, the chances for predation as ducklings leave the nest increase the farther the boxes are located from the water.”
Once a suitable nest location is identified, the height of the box also must be considered. A height of at least 6 feet is recommended, but other factors such as water level fluctuations should be taken into account. Water levels can vary greatly throughout the year in some locations. Nest boxes should be placed higher than the average annual high water events to avoid water fluctuation problems. In many situations, such as along larger creeks and rivers, wood duck boxes may need to be placed up to 20 feet above normal water level to avoid high-water situations.
“One important tool to help enhance nesting success in a wood duck box is the use of a predator guard,” Brock continued. “A predator guard should be installed below the box and, if the box is mounted on a tree, all limbs or other debris allowing a predator access to the nest should be removed. The box and predator guard should be checked and maintained at least once a year. During the inspection, repair any damage to the box and/or the guard. The inside of the boxes should be cleaned and three to four inches of new sawdust or wood shavings should be added prior to every nesting season.”
Be sure to document the nesting success of each box during the annual inspection. This can be particularly important information when deciding if more boxes are needed and also provides general information on reproductive success in the overall habitat area.
“Erecting and maintaining wood duck boxes is an effective wildlife management practice for areas where natural nest cavities are limited,” Brock concluded. “Utilizing the proper number of boxes that can be adequately maintained and monitored can provide years of enjoyment and add numerous broods of wood ducks to the population.”