Woodpeckers and Drumming

(Script by Francie Von Mertens)

In May, the dawn chorus of birdsong tunes up as more and more migrants return and join in. At last, we wake to the sounds of birds. Among the chorus, we hear the occasional drumming of woodpeckers.

People are often surprised to learn that woodpecker drumming has nothing to do with excavating a tree for food or a nesting cavity. The sounds of excavation don't carry far, but drumming certainly does.

Just as a robin sings for territory and for courtship, woodpeckers drum. Each woodpecker has its own preferred signal posts, usually dead, dry tree branches. Or TV antennas. When residential developments take over natural areas, woodpeckers occasionally adopt antennas or aluminum siding to broadcast their news.

The pair bond grows stronger as male and female drum to each other, select a nesting tree, and excavate a cavity. The pair bond needs to be strong because raising the next generation, from egg to fledgling, is a round-the-clock job that requires a committed partnership.

A lot of what is known about woodpecker behavior was discovered by Lawrence Kilham, of Lyme, New Hampshire. Kilham was a doctor and Dartmouth professor with a sideline interest in woodpeckers. Our largest woodpecker, the pileated, was Kilham's favorite. Unlike most birds, pileated woodpeckers mate for life, or until one partner dies. And, as Kilham discovered, a pair maintains close contact throughout the day by means of drumming, tapping, or "cuk cuk cuk" vocalizations.

He described a pair talking back and forth as they retired at day's end, each to its own roosting cavity, separate but close to one another. The male drummed the day's last message to his mate, an energetic, final good night from within his roosting chamber.