When we hear birds singing we often take it as a sign of warmer weather, but birds don’t sing just because it’s spring! Birds sing mainly to defend their territory or attract mates.

It’s worth mentioning that not all birds sing. About half of the world’s 10,000 bird species are not songbirds, and typically only make short, simple calls. There are even some birds like vultures that can barely produce a sound at all!

However, songbirds like thrushes, warblers, and sparrows can produce the beautiful, complex songs that many of us are familiar with. Often, only male birds sing, but in some species females sing as well. Bird song can be so complex because birds use a specialized organ called a “syrinx.” This is like a voice box in humans, however, birds can control the air flowing through their trachea to create two different sounds at the same time.

Most often, male birds will sing to mark and protect their territory. Singing sends a message to other males of their species that they are present and willing to defend their territory. Male birds also sing to attract mates. Female birds may take a strong, complex song as a sign that a male bird is healthy, and choose to mate with that male to give her offspring a good chance of survival.

Sometimes, both female and male birds sing together. Their combined song is often a part of their courtship ritual, and it also tells other birds that they are unavailable to mate. Birds can also sing for general communication, like sharing information about food or egg incubation.

Singing also has its drawbacks. Songs are loud and attention-grabbing, which can notify predators of a bird’s location. You may notice if you see a large bird like a hawk or other predator, birds that were singing before will go quiet. However, birds still sing because the benefits of claiming territory, finding and keeping mates, and communicating outweigh the risk.

Bird song may seem like just another noise we hear all the time, but it’s also a fascinating example of animal behavior!