Size and Sound in Birds
Streaming Audio

Listen:  Flash Audio Player
[Once the program is playing, click and drag across the volume bars to increase or decrease volume.]
Note: This audio requires the free Flash Player. Please let us know if you have any trouble playing this program.

Generally, larger birds have lower voices because their whole vocal apparatus is larger: longer and wider. But there are exceptions to this rule.

Here we use the example of the western screech owl. Although the female screen owl is larger than the male, her syrinx is smaller and her trachea (windpipe) is narrower. So, the male has a deeper hoot.

Chris Tenney recorded the house finch near Salinas. The recording of the American robin is from CD accompanying the Cornell Lab of Ornithology's Handbook of Bird Biology. The western screech owl duet is from the CDs accompanying the book Nature's Music: The Science of Birdsong.