Listening to a Continent Sing

During the first ten seconds, one hears two sharp calls of a western scrub-jay, together with wing sounds as it flies from branch to branch. The towhees then dominate the background, until a mourning dove on whistling wings flies in to a nearby perch; dissatisfied in some way, or perhaps with more pressing matters elsewhere, it takes wing again, each flap of its wings registering a nice whistle up around 2000 Hz.

It's nice to see (in a sonagram) and hear a bird's wingbeats, and I often wonder how rapidly a flying bird flaps its wings. The scrub-jay beats its wings 14-15 times each second as it flies from one perch to another. The mourning dove, when landing, is flapping 6-8 times each second, but when accelerating on take-off, it begins at 11 then slows to 6 beats each second.

And can this mourning dove choose to whistle or not to whistle with its wings when it lands and takes off? Almost certainly it can, but I wonder how, and why.

Background

Spotted towhee, Bewick's wren, black-headed grosbeak

Photo by John Van de Graaff

Photo by Wil Hershberger