Thursday, June 09, 2011

Wood Ducks Still on the Menu

There has not been a significant rain at the Audubon Center at the Francis Beidler Forest in quite some time.  A trip around the 1.75-mile boardwalk provides few opportunities to see water beyond the deep hole called Goodson Lake and the adjacent main creek channel.  However, behind the beaver dam there is still water, so that's where all the action is happening.  On Monday, we heard what sounded like trees rubbing against each other as a warm breeze blew over the swamp, but the sound at times appeared to originate from a wading bird of some sort or possibly an animal in distress.  We decided to investigate.

As it turned out, the sound was a combination of wind-generated tree rubbing and birds going about their business.  Once under the rubbing trees, the sound was distinctly tree-on-tree.  As the wind shifted directions, the sound generated by the trees changed pitch and volume, which caused some of the confusion at our listening post higher up at the nature center.  However, the water impounded under the power line by the beaver dam had attracted a host of bird species and their unique calls.

Several generations of Wood Ducks (Aix sponsa) were moving in and out of the tall grasses growing in the shin-deep water.  Adults seemed content to snooze, while juveniles and ducklings paddled about.  What sounded like children idly dropping stones into the water turned out to be ducklings returning to the water after launching themselves at drooping  grass seed heads.  In a classic mistake oft noted in the movies, we brought a knife to a gunfight.  Our mission was simply to scout sites for activities to be conducted during the upcoming summer camp sessions.   A camera was brought along to document the sites and anything of interest regarding camp.  The 21st-century camera with the lens capable of reaching out a greater distance would have been perfect for the 10-meter distance we were able to close on the Wood Ducks.

The Wood Ducks were not alone in taking advantage of the diminishing water resource.  Wading birds including Great Blue Heron (Ardea herodias), Great Egrets (Ardea albus), and a half dozen or more White Ibis Eudocimus albus) squawked and honked as they stalked prey and foraged in the shallow water.  Also calling along the treeline were Pileated Woodpeckers (Dryocopus pileatus), Red-bellied Woodpeckers (Melanerpes carolinus), Acadian Flycatchers (Empidonax virescens), Great Crested Flycatchers (Myiarchus crinitus), and several species of frogs.
As we watched and listened, a mass dropped from a nearby tree into the tall grasses that create a mini-marsh in the "pond" produced by the beavers.  At first we thought a squirrel had missed a step and fallen from the tree canopy as we have observed these accidents in the past.  However, the thrashing in the tall grass was caused by something considerably larger than a squirrel.  As the flapping increased, we determined the animal was a bird and by the size it had to be a raptor.  Based on our surrounding habitat, the prime suspect was a Red-shouldered Hawk (Buteo lineatus), which was confirmed as it cleared the tall grasses and headed to the treeline on the north side of the power line.  In its talons was a Wood Duck duckling destined to be the meal of one of the Red-shouldered Hawks recently fledged from the parking area nest.

It's a swamp out there!  For those of you keeping track on you food web diagrams, draw another line from Wood Ducks as they are now documented to be on the Red-shouldered Hawk's menu.

Images by Mark Musselman

1 comment:

William said...

I love reading and seeing what's happening at Beidler Forest. I want to get back out there soon. The spring was so beautiful and peaceful there. I hope we get some rain soon.