Saturday, August 15, 2015

The Pileated Woodpecker

World Bird Sanctuary staff, volunteers and guests have enjoyed some new sanctuary residents for the past few months.  A Pileated Woodpecker (Hylatomus pileatus, formerly Dryocopus pileatus) pair has taken up residence in the woods near the nature center.

Pileated Woodpecker pair_note the full red crown on the male at the left, while the female has only a partial red crown (photo: wikipedia)

The Pileated Woodpecker is the largest woodpecker in North America, measuring 15.7–19.3 inches in length with a wingspan of 26-29.5 inches.  They are nearly the same size as an American Crow!  They have a large black body, with white stripes on their head, a long neck, and sport a beautiful sweeping, triangular red crest atop their head.  Males have an additional red stripe on the face.  The beak is long and chisel-shaped, which is perfect for pecking trees in search of insects.  Their long, barbed tongue will then probe the opened tree (or log) and pull the insects out. This tongue is so long it actually wraps up and around the back of the skull when not in use.

This woodpecker used to be far more common – especially in the eastern half of the United States.  As trees were cut down in great numbers in the 18th and 19th centuries, their numbers declined rapidly.  However, since the turn of the 20th century, they have been increasing in number again.  Because of this, the sighting of a Pileated Woodpecker often invokes pure joy, even in a seasoned birdwatcher.

These woodpeckers are monogamous and hold a very large, year-round territory.  Unless you are lucky enough to see the young fledglings flying and foraging together, it is rare to see more than two at one time in any given area.  This territory is fiercely defended with loud drumming and ringing calls.  If one woodpecker of the pair loses its mate, it will however, take another.

A female Pileated Woodpecker searching a log for ants (photo: wikipedia)

Their very favorite food is carpenter ants, but they will also eat other ants, wood-boring beetle larvae, termites, and other insects such as flies, spruce budworm, caterpillars, cockroaches, and grasshoppers.  They also enjoy wild fruits and nuts; including greenbrier, hackberry, sassafras, blackberries, sumac berries, poison ivy, holly, dogwood, persimmon, and elderberry.  When looking for food they will excavate a characteristically rectangular hole in the tree.  They sometimes make such large holes that they can break a smaller tree in half.  Other birds – such as house wrens and other woodpeckers - may also come to enjoy the many insects revealed by the massive Pileated Woodpecker excavation.

A male Pileated Woodpecker excavating a tree in its search for insects (photo: wikipedia)

Their long, graceful neck comes into great use when the woodpecker is pecking the tree.  The longer neck allows the bird to pull its head further back from the tree to obtain a longer and stronger pecking action.  They will also simultaneously pull with their feet to increase the strength of the blow. 

A spongy, plate-like bone structure in the skull protects the birds' brains from injury during this aggressive process. They also have little subdural space between their brains and their skulls, so the brain does not have room to bump around as it would in humans.  In addition to this, their brains are longer top-to-bottom than front-to-back, meaning the force against the skull is spread over a larger brain area.  This unique anatomy has been the inspiration for vehicle shock absorbers in aircraft and spacecraft, for improving seat belts, and for designing better sports helmets.

A Pileated Woodpecker feeding from a suet feeder strategically placed amongst a grove of large trees (photo: Gay Schroer)

Pileated woodpeckers will live among both deciduous and coniferous trees.  For nesting sites, they choose the largest, oldest, dead tree in the forest.  These trees are not easy to come by, as the woodpeckers compete with around 85 other species of birds and about 45 species of mammals for the rights to this perfect nesting site.  The male woodpecker will shoulder the majority of the work when excavating their nesting cavity.  The female generally contributes when the hole is near completion, at about 10-24 inches in depth. These birds do not line their nests with anything except some of the leftover wood chips.

Three to five white eggs are laid in the nest and are incubated by both the male and the female.  The male generally takes the majority of the night shift and part of the day.  The nestlings are fed by regurgitation from the parents and they will leave the nest 26-28 days after hatching.  However, the youngsters may remain with the parents for an additional 2-3 months.

Pileated woodpeckers are fun to watch.  It is always a little surprising to see such an unusually large bird fly by!

 Come out to the World Bird Sanctuary and spend the afternoon walking and relaxing.  Have a picnic lunch on the grounds and do some bird watching, either strolling our grounds or sitting on our conveniently placed benches. Our surrounding hardwood forest attracts a wonderful collection of wild birds, mammals, reptiles, amphibians and insects. Take your time to breathe in the beautiful outdoors. Your peaceful, quiet day just might be interrupted by the raucous call and foraging drumming of the Pileated Woodpecker!

Submitted by Dawn Trainor Griffard, World Bird Sanctuary Naturalist

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