Sunday, November 13, 2011

The Elusive Wood Duck

If you have never seen a male Wood Duck (Aix sponsa), then you are missing one of nature's works of art!  In fact, hunting this bird for its plumage and as food brought the species to the brink of extinction by the early 1900s.

male

Wood Ducks nest in cavities, natural or made by other animals, so they are often found in swamps and bottomland forests.  Loss of habitat and some forestry practices eliminated the nesting cavities sought by this species, which is the reason Wood Duck nest boxes became ubiquitous in some areas.  While the practice of placing nest boxes helped the species recover, more is not necessarily better as female Wood Ducks increase their habit of dumping eggs into other birds' nests as the density of cavities or nest boxes increases.  Clutches of 15-50 eggs can result from 2-10 hens contributing eggs to the nest.  Cavities may be quite high in a tree, but 24 hours after hatching, the ducklings will exit the cavity and free fall.  Their light weight and landing zones of soft leaves or water results in few injuries.

 female behind male

Over the last two weeks, Wood Ducks have gotten our attention at the Audubon Center at Francis Beidler Forest as their noisy courtship has begun. The female's vocalization, heard at the end of this audio, is what can be heard most often from the boardwalk and our offices. Displays will continue into the spring as groups of a dozen birds, more males than females, gather to court and eventually split into monogamous pairs. These displays occur mainly on the water.  The heavy weight of ducks relative to their wing area requires continuous flapping and makes aerial maneuvers and displays difficult to impossible.

 male

The wet area behind a portion of the beaver dam (small portion shown in blue) near #1 along the boardwalk is where the Wood Ducks have been located.  As our Wood Duck images consist of distant blurs or the ones above taken inside at the South Carolina Aquarium, we wanted to try and capture some clear images in the swamp.  Down the hill from the outdoor classroom, there was a screen of large trees between us and the ducks.  We moved slowly and quietly while frequently checking with binoculars the location of our quarry.  Occasionally, a duck would swim out from behind the screen of trees and we would freeze until the duck returned to a position out of our view.  Quite pleased with our stealth, we arrived at a position close enough for our long lens to provide a quality image.  Alas, there were no ducks!  Scanning with the binoculars, we located a male watching us from a position 50 meter to the south.  Upon further inspection, we saw additional ducks silently swimming south down the channel.  As the trees screened us from the ducks, or so we thought, so too was the ducks' exit screened from us.  Visitors passing along the boardwalk caused the ducks to flush to flight, which revealed the presence of at least a dozen ducks when we had seen no more than five.  Obviously, we were not as stealthy as we thought and had been under careful observation the entire time, which allowed for the ducks' silent withdrawal.

The elusive ducks won again.  However, trips into the swamp would be less exciting if we did not have plenty of targets still on our image wish list!

Images by Mark Musselman

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