What is the collective singing of many birds around sunrise called?

The collective singing of many birds around sunrise is called the dawn chorus.

The dawn chorus is a widespread communication event in which birds sing most actively during the early morning. Males commonly use their songs to defend territories and attract mates, so the chorus is both competitive and reproductive.

Researchers have proposed several reasons for its timing. Light levels are often still too low for efficient foraging, while cool, calm air can help carry sound. The precise order of singers varies with habitat, weather, season, and species.

The dawn chorus is not a single song shared by all birds. It is a layered mixture of species-specific songs and calls. Familiar participants can include blackbirds, robins, thrushes, and great tits, depending on the region.