BirdNote®: Why Dippers Dip
Air Date: October 04, 2013
The American Dipper is a favorite bird of the west, but exactly why dippers dip is a bit of a mystery. Michael Stein reports.
Transcript
CURWOOD: We have a much more soothing kind of story now - the mystery of exactly why a familiar bird of the American west does what it does. Michael Stein has our BirdNote®.
WATER RUSHING, SOUND OF CHIRPING
STEIN: An American Dipper calls across a rushing mountain stream. Its rotund, stone-gray body bobs rhythmically up and down, its feet firmly planted. The bird’s white-feathered eyelids flash like a semaphore.
CHIRPING AMERICAN DIPPER
So why do dippers dip? Let’s consider three theories: One suggests the dipper’s repetitive bobbing against a background of turbulent water helps conceal the bird’s image from predators. A second asserts that dipping helps it sight prey beneath the surface of the water. A third theory holds the most promise. Dipping, as well as the rhythmic flicking of those flashy white eyelids, may be a mode of visual communication among American Dippers in their very noisy environment. That dippers make exaggerated dipping movements during courtship and also to threaten aggressors lends support to this theory.
WATER RUSHING IN MOUNTAIN STREAM
So if one day, as you muse alongside a mountain stream and an American Dipper bobs and winks in your direction, don’t take it personally. It’s probably beckoning to another dipper upstream.
I'm Michael Stein.
CURWOOD: There are photos of dipping dippers at our website, LOE.org.
birdnote.org/show/why-dippers-dip Written by Bob Sundstrom Song of the American Dipper and Riparian Zone Nature SFXs #119 and # 17 recorded by Gordon Hempton of QuietPlanet.com Some stream ambient recorded by C. Peterson Producer: John Kessler Executive Producer: Chris Peterson © 2013 Tune In to Nature.org September 2013 Narrator: Michael Stein
