Why do we have a dawn chorus?

The song of the birds at dawn has given pleasure to millions of people has been celebrated in poetry and prose for many years. The most usual explanation given in the Middle Ages was that the birds sang each day in praise of God and the beauty with which, he had clothed the world. More recently, there was the feeling that the birds sand joyously to welcome the rising of the sun, which mean food, warmth and activity.

However, scientists now think that the dawn chorus is made up of the warning signals of each bird as he re-establishes his territory. The establishment of a territory for courtship, nesting and food getting is the first step in the breeding cycle and the are is defended against competing birds of the same species by the warning song, although seldom by actual fighting. A robin, incidentally, has particularly strong sense of territory.

Song of Birds, Middle Ages