What are the main purposes of bird communication through sound?

          Sounds become part of a bird’s life from the very moment they are born.

          It is wrong to think that the only sounds made by birds are songs. There are a variety of others too, like alarm calls, begging calls, contact calls, flight calls etc., used by them, depending on the circumstances.

          Songs are of course the most distinctive and familiar sounds. They are used mainly to attract mates, mark their territories, or discourage intruders. The quality and duration of a song depend on the species. Some may have different songs for different times of a day, but some sing only in the morning or evening. The yellowhammer, for instance, repeats its song around 1000 times a day.

          Begging calls are usually made by young birds to draw attention. Contact calls, on the other hand, are used to signal one another, particularly while travelling in a flock.

          In addition, there is something called the dawn chorus. It occurs when a large number of birds sing at the start of a new day. This is done either to protect a territory, or to call in the flock.