Sunday, May 08, 2011

Boardwalk Assassins

No, Boardwalk Assassins is not the title of a new movie based on a best-selling novel.  The title refers to the experience we had last night while waiting for darkness and the arrival of Dr. Brian Scholtens from the College of Charleston.  Tomorrow's blog entry will cover what we learned during Dr. Scholtens' visit regarding the insect community here at the Audubon Center at Francis Beidler Forest.

Having been in the building all day running the front desk, we needed to stretch the legs before the evening insect activity.  We've learned to take along the camera, even if the light is rapidly diminishing, because one never knows what will be seen in the swamp.  Each trip onto the boardwalk through the old-growth, cypress-tupelo swamp is guaranteed to be a different experience and frustration is seldom greater than not being able to capture a rare sighting.  The saying in the education department is, "If you don't have a picture, it didn't happen."  Turn away now if you do not want to see owls killing ducklings, because we have the pictures.

Wood Ducks on an earlier day in the power line right-of-way

Walking at a rapid pace along the return side of the boardwalk loop near #15, we heard a female Wood Duck continuously calling.  Usually, the only sightings we have of a Wood Duck (Aix sponsa) during the breeding season are by chance as she silently paddles away with her ducklings.  This hen was making a racket!  It soon became apparent that the cause of her stress was a pair of Barred Owls (Strix varia) perched low over the creek channel in which the ducks were moving.  This is not unusual owl behavior in the swamp as owls frequently hunt crayfish in the shallow water.  Tonight, however, the adult owls were serving ducklings to their young.

With each pass of an owl, the Wood Duck hen rose out of the water, flapping her wings and calling loudly.  The owls were unfazed and simply maneuvered around the hen and snatched a duckling.  After each attack, the ducks moved on with the hen continuing to protest.  Hearing the begging of its own young, the adult owl would carry a captured duckling to its offspring.  The lulls between attacks were only as long as it took the young owl to consume the duckling.  Once the begging began once more, the adult owl would reacquire the ducks and begin another attack glide.  Immediately, the hen would increase the volume and frequency of her calls and rise up to defend her young.  Each time the owls succeeded in removing a duckling from the group.

Eventually, the Wood Duck hen took her remaining ducklings out of the creek and into the forest where the Dwarf Palmettos appeared to offer some cover from the avian predators.  The results did not change for the duck, but once an owl had a duckling on dry land, American Crows began harassing the owl in hopes that the duckling might be dropped.

There is a reproductive strategy for having large numbers of young.  Not all will survive, but enough will survive to ensure the species continues to exist.  Today, the cells of growing Barred Owls along the boardwalk near #15 are being fueled by Wood Ducks, which previously received their energy from plants...and life goes on.

Images by Mark Musselman


J. Drew Lanham said...

An amazing sequence of events that graphically illustrates that there is no "cute" in the wild--only survival. Great job capturing this, Mark!


Sparkle Clark said...

Awesome photos Mark! Thank you so much for sharing.
BTW, what got the 5 Protho chicks near the lake the other day?
I love nature, but sometmes it is so sad.
I enjoy all your updates. Your pictures tell the story.

Mac Stone Photography said...

Mark! These are awesome! Great captures and way to be there with your camera.