Monday, May 6, 2013

Why do birds sing in the early mornings?

Sunrise at the Aldo Leopold Nature Center
With the warmer weather we've been having, it's been necessary for me to sleep with the window open at night (and maybe even with the fan on, too). I am finding that this inevitably means that I will wake up to birds singing sometime between 3am and sunrise. Some even continue through the night! I'm usually immediately upset that these birds woke me up, but it did get me thinking; why do birds sing in the early mornings?

After some digging around, I can tell you that it is mostly the male birds who make up this morning ruckus. Research has pointed to two reasons why male birds sing in these dawn (and pre-dawn) hours: to warn other male birds of their territory and to let females know that they are around and are looking for a mate. It is also notable that male birds sing in the spring because it is breeding season, and they are trying to defend their breeding territory. For better or for worse (for our spring slumber), most birds have developed special adaptations that allow them to sing so loudly, steadily, and with beautiful musical variation. Learn more about bird musicians and their incredible vocal abilities.

Other research tries to understand why male birds find it necessary to sing so early. One theory is that dawn is the best time for song travel because there is less heat and wind to interfere with the acoustics. Another theory is that singing in the morning leads to a more consistent signal to other male birds, and the earlier the better. To my understanding, there is not one theory that has been proven over another, and it may be a combination of reasons. (The Cornell Department of Ornithology also has great resources and research on general bird information, bird songs, and why they sing in the mornings.) What is for certain is that I will wake up everyday to birds chirping. It could be worse, right?
Aldo Leopold's Shack in Baraboo, WI

Aldo Leopold, well known for phenology, conservation, and wildlife management at the University of Wisconsin-Madison, actually wrote about these morning songs in his essay "Great Possessions." In addition to being a curious and meticulous naturalists, Aldo happened to be a very early riser! He was one of the first people to link individual bird species with their arrival to the dawn chorus and association with the amount of daylight. Because his notes were so thorough, Dr. Stanley A. Temple, a University of Wisconsin-Madison emeritus professor was able to use them much like a musical score to recreate a soundscape of what the Leopolds likely heard each morning at their shack in Sauk County. Listen to it here!

Are you interested in recording your own dawn chorus notes? Contribute your seasonal observations and learn more about nature journaling and phenology from this Nature Net blog post. If you're more of a techie, you can also use technology to record your nature observations. I also discovered that yesterday happened to be International Dawn Chorus Day! To further celebrate these early orchestras, visit their website and learn more about songbirds and their morning music across the globe.

Do you enjoy this dawn chorus? Does it wake you up or do you sleep through it? Leave your comments below!

Happy Spring,
Nature Net Intern