Air Date: Week of May 20, 2011

The complex song of birds is produced by a tiny, yet efficient, organ called the syrinx. Michael Stein tells us how it works.

Transcript

GELLERMAN: From lions and tigers and bears to - oh my - birds.

[BIRD NOTE THEME]

GELLERMAN: Bird songs are complex - calls and melodies vary by species and purpose. And producing them is complex as well. Here’s Michael Stein of BirdNote®.

[CALL OF THE BRANDT’S CORMORANT; SONG OF THE NORTHERN CARDINAL; SONG OF THE SONG SPARROW]

STEIN: You just heard the grunt of a cormorant, the whistle of a cardinal, and the song of a Song Sparrow. Nearly all birds produce sound through an organ unique to birds - the syrinx.

[SONG OF THE CARDINAL]

STEIN: The syrinx is a set of muscles and membranes located where the two branches of the bronchial tubes converge to become the trachea. An adjacent air-sac helps build pressure in the syrinx. In many songbirds, this whole song-producing apparatus is not much bigger than a raindrop.

The syrinx is extremely efficient at creating sound, using nearly all of the air that passes through it. By contrast, we humans create sound using only two percent of the air we exhale through our larynx. Let’s listen again to the limited vocal range of the cormorant, whose syrinx is controlled by only one set of muscles.

[CALL OF THE CORMORANT]

STEIN: The cardinal, a familiar bird of central and eastern states, creates its pure whistle by producing sound in its left and right bronchial tubes simultaneously.

[SONG OF THE CARINDAL]

STEIN: The Song Sparrow, like many other songbirds, has five to seven pairs of muscles that govern the syrinx. It puts forth a cascade of trills and notes, as if singing a duet with itself.

[SONG OF THE SONG SPARROW]

GELLERMAN: That’s Michael Stein with BirdNote®. And you can wing your over to our website for photos of Song Sparrows. It’s L-O-E dot O-R-G.

 

Links

Bird sounds provided by the Macaulay Library of Natural Sounds at the Cornell Lab of Ornithology, Ithaca, New York. Brandt’s Cormorant recorded by G.F. Budney; Northern Cardinal recorded by G.A. Keller; Song Sparrow recorded by G.A. Keller.

BirdNote® How Birds Produce Sound was written by Chris Peterson.