Birds sing so early in the morning ?
Singing is an essential part of bird life, but it’s costly in terms of time and energy, the atmospheric conditions in the early morning i.e. typically cooler and drier than later in the day, might allow bird song to travel further through the air. Individual males have their own signature songs, with slight variations that identify them to their neighbors.
If you’re a male trying to attract a mate or defend your territory, it’s more important to let your fellow birds know that it’s you singing than it is to be heard over a long distance. Most birds do their singing in the early morning, and in most species the male is the vocalist .
The dawn is the best time for song travel because there is less heat and wind to interfere with acoustics. The singing in the morning leads to a more consistent signal to other male birds, and the earlier the better. Mostly males singing, because they typically take the lead in defending territories and attracting mates.
However, especially in the tropics, some species sing duets involving both the male and female. Many birds sing especially energetically at dawn.