This is bird note.

For most birds, wings are for flying.

For penguins, they're for swimming.

But for rock pigeons, they're also for clapping.

Startle a flock of rock pigeons, and you'll hear something like this.

Wing flaps mixed with the sound of clapping.

When rock pigeons erupt into flight, some of them may slap their wings together above their bodies.

It's called a wing clap.

A male rock pigeon will do this when courting.

He'll posture and coo alongside a female.

Then fly sharply upward in an aerial display. The brisk series of claps is a shout-out of his courtship plans to the female watching from the rooftop.

Short-eared owls have evolved wing-clapping, too.

These medium-sized owls fly by day on long wings, rounded at the tip,

and mostly they fly slowly, gracefully, like enormous moths.

But when a male displays to a female or attempts to warn off an intruder,

he snaps his wings together below his body in a burst of two to six claps per second,

producing a sound that sounds remarkably like applause.

For Bird Note, I'm Michael Stein.