We hear them at dawn, birds singing at the top of their lungs in spring. But why are these songs so frequent and varied during this season? The answer lies in a mix of instinctive behaviors, biological signals and reproductive strategies unique to birds.
Spring marks the return of longer days and milder temperatures. These environmental changes stimulate hormone production like testosterone in male birds, prompting them to sing more intensely. Songs primarily play a role in reproduction: they allow males to signal their presence and territory to other males, while attracting females ready to mate.
Illustration image Pixabay
Scientifically, birdsong is a manifestation of acoustic communication, a sound language that varies by species. Each species has its own repertoire, composed of notes, trills and repetitive patterns. These songs serve as an audio identity card: they allow females to recognize males of their species and choose a quality mate, often based on the complexity or power of the song.
Songs can also play a defensive role: when a male sings, he signals to other males that he occupies a given territory. Intruders hearing this song are often deterred from entering the territory, avoiding physical fights and unnecessary injuries. Thus, singing is an effective strategy to limit competition and secure a space for finding food and mates.
From an anatomical standpoint, birds produce their songs thanks to a unique organ called the syrinx, located at the base of the trachea. This organ allows them to produce varied sounds and even sing two notes simultaneously, thanks to its particular structure and fine control of associated muscles.
So if birds sing so much in spring, it's because this season corresponds to the breeding period, and singing is their primary means of communication to attract a mate, defend territory and assert their presence. It's a vital behavior for species survival, and a sound spectacle that accompanies us from the first light of day.