With Recordings Inspired by Donald Kroodsma
Did you know that some songbirds have 2 voiceboxes? I didn't either until about 4 years ago when I heard ornithologist Donald Kroodsma on NPR's Fresh Air Program. Kroodsma has been recognized by the American Ornithologists' Union as "the reigning authority on the biology of avian vocal behavior."
At that time, his new book "The Singing Life of Birds" had just been released. In the program, host Terry Gross played a number of birdsongs that are on the CD that accompanies the book, with Donald providing fascinating explanations.
After listening to the program, I became enamored with the song of the Wood Thrush, one of the songbirds that has 2 syrinxes (voiceboxes). Kroodsma's recordings of the thrush were first at full speed and then slowed down in order to hear as the bird "sings a duet with himself." Kroodsma shares that the "left voice box specializes in low sounds, the right one in high sounds."
Fast forward a couple years to this summer. I've had resident Wood Thrushes singing in the surrounding woods not only at daybreak and at dusk, but all day long. I took my low tech computer microphone, set it in front of my sound monitor and recorded this song of the Wood Thrush. (A 13 second recording. Make sure your speaker volume is high. The quality is not great, with a bit of a buzz, but bear with me.)
Then I used my equally low tech Microsoft Sound Recorder to slow the Wood Thrush song down, à la Donald Kroodsma. (A 27 second recording.)
And then slowed I slowed the song down once more. (A 55 second recording.)
I find the slowed-down recordings, even with my primitive equipment, simply amazing. So haunting, so mesmerizing. And just like Kroodsma says in his book, I will never "hear a Wood Thrush singing in the same way again."
If you'd like to hear high quality recordings of the Wood Thrush, Terry Gross' interview with Donald Kroodsma is still available to listen to online. His book is The Singing Life of Birds: The Art and Science of Listening to Birdsong, which includes a CD with 98 birdsong tracks, including the Wood Thrush.
All quotations in this post were taken from Kroodsma's book.