Wood
Duck
When populations of the handsome
Wood Duck began to plummet in the late 19th
century from over-hunting and loss of wetland
habitat, many North American ornithologists
predicted that the species would soon become
extinct. However, several decades of closed
hunting seasons for Wood Ducks allowed the
species to recover dramatically, and today it
occurs over a wider area of North America than
ever.
Wood Ducks are now hunted again, and it is the
actions by, and on behalf of, these hunters that
have resulted in large-scale conservation of
wetlands.
One factor that has aided the Wood Duck's
recovery to historically high population levels
is its high reproductive rate. Females typically
lay 10 to 14 eggs, and some may deposit eggs in
other Wood Duck nests before laying full clutches
of their own.
In many locations artificial nest boxes have
helped the Wood Duck's recovery by providing nest
sites where tree cavities, the bird's natural
choice, are unavailable.
In pre-colonial times, the wood duck was likely
the most abundant waterfowl species in eastern
North America. Unfortunately, their distribution
within densely settled regions made them readily
accessible to market hunters throughout the year.
Over-harvesting coupled with the destruction of
bottomland habitats drove these colorful birds to
the brink of extinction by the early 20th
century. The dramatic rebound of wood duck
populations since that time can largely be
attributed to protection provided by the Migratory Bird Treaty Act of 1918.
However, the recovery of the wood duck was also
assisted by the advent of artificial nesting
structures, or wood duck boxes.
In 1937, the U.S. Biological Survey (now the U.S. Fish
and Wildlife Service) erected
486 bark-covered slab wooden boxes, which were
thought to be designed by biologists Gil Gigstead
and Milford Smith at Chautauqua National Wildlife Refuge in central
Illinois. This represented the first recorded use
of artificial nesting structures for wood ducks.
Over the next two years, Arthur Hawkins and the
renowned wood duck expert Frank Bellrose erected
700 rough-cut cypress board boxes throughout
Illinois. More than half were used by woodies,
revealing the great management potential of the
boxes. Since those pioneering efforts, thousands
of wood duck boxes have been built and erected by
a diversity of people and groups, from wildlife
agencies to conservation-minded private citizens.
Wood duck females typically build their nests in
tree cavities near wetlands. When a prospective
cavity is found, a hen wood duck will land in the
tree and carefully inspect the site for a variety
of characteristics, including size, shape, and
security from predators and the elements. In many
areas, wood ducks have difficulty finding
suitable natural nesting sites. Wood duck boxes
provide a man-made alternative, where hens can
nest in relative safety from predators. The
deployment of large numbers of nesting boxes can
be used to help increase local or regional
populations of wood ducks in areas where natural
cavities are limited.
Several important factors must be considered when
selecting sites to place wood duck boxes.
Suitable brood habitat must be available within a
couple of hundred yards for the ducklings to
survive once they exit the box. Shallow, fertile
wetlands with thick cover and an abundance of
invertebrates typically provide the best habitat
for broods. Ideally, boxes should be erected on
either wooden posts or metal conduit outfitted
with predator guards.
While many types and styles of wood duck boxes
have been produced from a variety of materials
over the years, those made from rough-cut lumber,
like the original prototypes built by Hawkins and
Bellrose, seem to work best. Rough-cut,
unfinished lumber is preferred because ducklings
have no trouble climbing the inside of the box
with their sharp claws to reach the exit hole. In
plastic or metal structures, which have slick
surfaces, hardware cloth ladders must be
installed to provide ducklings with an escape
route. Additionally, a four-inch layer of wood
shavings or sawdust should be added to each box
for nesting material. The female will use this to
cover the eggs during laying or when she takes
feeding breaks during incubation. Boxes should be
cleaned out and replenished with fresh nesting
material every year in late winter, before hens
initiate nesting in early spring.
All nesting boxes should be secured to protect
hens and their clutches from nest predators,
especially raccoons and rat snakes. The most
effective way to provide defense from these
marauders is to install a predator guard on the
pole supporting the box. Conical predator guards
made of sheet metal are most effective. Care must
be taken to ensure that the guard fits tightly
against the post and that no overhanging tree
limbs allow predators to bypass the predator
shield.
Although duckling production from nest boxes
represents only a small percentage of that
produced from natural cavities, wood duck boxes
provide an excellent opportunity for anyone to
become involved in wildlife management. By
building, installing, and maintaining nest boxes,
individuals can gain insight into the interesting
aspects of wood duck nesting and reproduction,
while helping to boost local populations.
Visit Shaw
Creek Bird Supply to see our selection of Wood
Duck Houses.
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