Birdsong is mostly produced by males to defend territory and attract mates.

The longer version

Song is produced in the syrinx, a vocal organ at the fork of the windpipe where membranes vibrate as air passes. Males sing most because they compete for territories and for mates, and song carries identity and condition at once. A long, complex performance advertises a bird that survived and fed well.

Females of many temperate species sing far less, but in the tropics female song is common and pairs often sing in duet. Song also works on males, warning rivals that a territory is taken and heading off real fights. Playback tests show a territory holder will attack a speaker playing a stranger's song.

Where this entry sits

Here you will find feathered trivia about flight, migration, nests, eggs, and the songs birds sing. Expect short surprising facts on penguins, owls, hummingbirds, and other familiar birds from gardens, forests, wetlands, and distant coastlines. The full list sits on the Birds page, where every entry is listed in order.