There is something about waking in the dark well before any need to plan the day or check the news. It can be a time of inward receptiveness, a pause, an opening to nothing and everything. And without knowingly listening, a sound arises, here, then there: bird song. But it is still quite dark! The singing is brief and tentative, a kind of trying-out of a trill or warble. A warming up of the vocal chords?
But then, there is more: a sustained series of notes, less interrogative, more of a statement, a declaration. A voice calls from one direction; another perks up and begins to call attention to itself from another place. Soon there is song swelling from every nearby bush or tree. The sky, without making a sound, empties its darkness from black to intense blue, a midnight blue, and then spreads a watery warmth from a far edge upward. The moment before dawn. The birds send up their chorus to greet the day. It never fails to thrill.
I remember such moments as a child, waking early and slipping over to the bedroom window to watch the light spread in the sky and listening to birds singing the new day into existence. And the time I raced the light across town to join friends on a dawn walk through woods to hear the birds. Lucky me to have birding friends who could call the names of the singers by ear and who were attuned to all the songs as we moved quietly along the trails first in the darkness and as the sun brightened the horizon. A great feeling of peace and well-being suffused the moment.
But for the birds, this singing has a different imperative. It is a competition, a challenge, an urgent call of territory and mating siren. It has nothing to do with the ecstasy of sunrise. Except that it does, in a way very different from our human romanticism.
As reported on the Cornell website, a bird researcher, Karl Berg, discovered that that the dawn chorus was a precisely organized orchestration; there was nothing random or spontaneous about the songfest. The research team found that “each species started singing at a specific time relative to first light.” They were able to correlate this sequencing in relation to “each species characteristic foraging height and its eye size. Species that forage higher in the canopy or have larger eyes sang earlier than others.” This is so intriguing!
Further, “this suggests that light levels are responsible for the timing of singing. Leaves and branches shade out lower levels of the forest so that the forest floor takes longer to brighten than the canopy. Birds with different eye sizes perceive light levels differently at the same height, because larger eyes gather more light than smaller ones. At some point around dawn, each species may have enough light to see predators and competitors, before there is sufficient light to effectively forage for food. It may sing at its maximum rate for the day until the point when there is enough light to forage.” And at that point, the singing dies down. It’s breakfast time, a different imperative.
The dawn chorus will still feel magical to the listener lucky enough to awaken in time but now feels like it has gained a level of complexity never guessed at before. I know only a few bird-calls with any certainty. I could hear robins and a cacophony of “probables” as well as a buzzing sound that I attributed to a wren. Later in the day, I did see a wren skittering around in the camellia bush. Aha! But as to eye size and height of foraging…I’ll have to leave that to the ornithologists. Fun to think about, though!
For more on this research, see the Cornell Lab website at: https://www.allaboutbirds.org/news/who-sings-first-during-the-dawn-chorus-and-why/