Have you ever been awoken early in the morning to the sound of birds singing loudly outside your window? You’re not alone.
Birds have a way of making their presence known even before the sun rises each day. In the spring especially, they can create quite a racket.
Birds singing early in the morning is called the dawn chorus. And the birds aren't just greeting the new day with a cheerful good morning. It doesn't have anything to do with the early bird getting the worm, either.
Most of the songs we hear birds singing in the morning are the work of male birds. They are looking to attract a mate and establish a territory.
Words to know
Crooner: A singer, typically a male.
Vocal: Relating to voice.
When you think about it, the predawn hours are a good time for birds to be singing loudly and proudly. The darkness of early morning makes it too difficult to spend time searching for food. It's also too dark for many predators to be on the prowl. Plus there's not as much noise being generated from other activity like traffic, so a bird's song can carry as much as 20 times as far as it might later in the day.
At one time, researchers believed birds were also taking advantage of the cooler, drier air in the morning. They thought this allowed their notes to carry a little farther, but research has shown that's not the case. Their notes carry as far — or farther — at midday than in the predawn hours thanks to their early-morning vocal warmup, according to research conducted at Duke University.
The Duke researchers had a theory that the songbirds' early morning concert is a warmup so they can perform better later in the day. They tested their theory by studying the behavior of a group of male swamp sparrows between 2 a.m. and noon for two to three mornings per bird.
In all, they analyzed more than 1,500 swamp sparrow songs. They found that the birds' vocal ability improves as the day goes on. This allows them to sing more complicated notes and songs as the day progresses. The study demonstrated a clear improvement in singing ability after the birds' early-morning warmup, but researchers still aren't certain what causes their singing to improve.
Does the chorus of birds seem to start hours before the sun rises in your neighborhood? That could be because of where you live. The dawn chorus typically begins shortly before sunrise, but it starts earlier in cities. This may be because artificial light makes it seem like the day is starting even before the sun comes up. In addition, clouds and other weather conditions can more easily allow light to be reflected back to the ground in urban areas.
A strong singing voice is important for male birds because it is a sign of health and strength. These are qualities potential mates are looking for.
For most birds, spring and summer are prime singing season because it is breeding season. Hearing birds sing at other times of year is not uncommon, though. Some species also sing to warn off predators or intruders on their territory or to communicate with other birds.
While males are the primary crooners in the bird world, some female songbirds sing too. Both male and female cardinals carry a tune, for example.
Other female singers include eastern phoebes, purple martins, barn swallows, black-capped chickadees, gray catbirds, European starlings, eastern towhees, song sparrows and house finches. Do you see any of these birds in your neighborhood? Female birds sing for the same reason as males: to defend their territory and communicate.
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