Why do birds sing at dawn?
Wake up early enough and, depending on where you live, you'll likely hear
a pleasant chorus of birds chirping their tiny hearts out. This am avian arrangement
is instinctual behavior for birds, but why?
According to the Woodland Trust, this early singing is known as the dawn chorus, and
it can start as early as 4 am and last for several hours. Birds do it to attract mates
and warn other birds to avoid their turf. One theory as to why they opt for the wee hours
to communicate these important messages is because the low visibility makes it hard
to do other bird activities, like foraging. Keeping their activity level
low, they opt to sing instead.
Another theory argues that birds use the morning vocals to project an image of
strength. By singing with fervor, they're letting other birds know they survived
the night-no guarantee in nature-and would make for an excellent mate.
Like a good recording studio, the early morning hours also allow birds to transmit a
clear tune thanks to the cooler, drier air. Because birds have distinctive chirps, that
clarity helps them be more easily identified by birds within listening distance.
There used to be a prevailing theory that birds sang so much in the mornings because
the sounds could travel greater distances due to less atmospheric turbulence, but it
was disproven by researchers at the University of Western Ontario in 2003. They played
recordings of sparrows at dawn and midday. The songs didn't travel farther, but they
were more consistent.
Because birds only have so much energy to belt one out, singing when they stand the
best chance of being heard makes sense. For a bird, an early morning session is like
having the perfect acoustic environment for their performance.
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