Why do birds sing?

Birdsong is an acoustic marvel. But why do birds sing? And why do some birds sing in the morning, and others in the evening or at night? Read on to find out!

There is nothing better than hearing a dawn chorus. Each morning, birds announce the start of the day with dulcet tones. But why do birds sing? And why do we hear so many birds in the early morning and so few in the evening or at night? What about winter bird song – is it the same sound as in spring and does it serve the same purpose? Read on for the answers to all these questions and more.

Why do birds chirp?

Bird song and bird calls are a form of communication. Bird song is classified as one melodic verse and is a different sound to a bird call, which tends to be constructed from a few short sounds. While some species have one unique song, others have a more varied repertoire, and communicate with a wider range of sounds and melodies.

Bird song is mainly heard during breeding season. It serves to mark out territory and attract a breeding partner. In this case, it is usually only the male bird who sings in the hope of attracting a mate. Read more about courtship and bird mating in our special article.

Bird calls, on the other hand, are more functional. Calls are used to stay in contact with other members of the flock and to warn others of danger and predators. Young birds use their call to signal to their parents that they are hungry.

Discover whether birds can smell, hear and see colour in our article on bird senses!

Discover whether birds can smell, hear and see colour in our article on bird senses!

Why do birds sing in the morning or in the evening?

Most birds sing in the early morning hours. The reasons for this have long been discussed, and scientists have considered several theories:

1. With less wind and air movement in the morning, bird song carries further.
2. Birds are unable to forage well at dawn due to the lack of light and warmth, and those birds that feed on insects must wait for their prey to become active. Therefore, they use this still, morning time to sing.
3. A hormone, melatonin, which – much like in humans – controls the animal’s internal clock, stimulates the birds’ singing in the early morning.

Whatever the reason, one thing is clear: it would be unproductive for all birds to sing at the same time. Their songs would overlap so much, that no one bird would be unable to distinguish any other.

As a result, some birds prefer to sing in the evening hours. In fact, different bird species sing at different times in the morning. The redstart, for example, starts singing about an hour and a half before sunrise, while the chaffinch and greenfinch only start singing when the first rays of sunlight appear. It is this protracted singing that is called the “dawn chorus”.

Find out more about “nocturnal birds” in our special article.

Why do birds chirp in different seasons?

Once the mating and breeding season (the main reasons for singing) come to an end in late spring, the bird world appears to fall silent. Many of our native migratory birds leave their breeding grounds at this time, only to return in spring.

However, some of the remaining resident birds and birds that migrate only a short distance begin to sing in autumn, and can even be heard in the depths of winter. They sing in order to mark feeding territories in the barren winter landscape, which tends to be more extensive than summer breeding territories. 

Tip: If you are new to bird watching and want to learn more about bird song, it is a good idea to start listening in the winter months while there are less birds around. You can build up your repertoire slowly and will be ready to learn new bird song when spring arrives.

Find more practical tips on birdwatching in our special article.