For millions of years before the first humans sung a tune or carved a flute, the birds -- and who knows, perhaps even the dinosaurs and other beings before them -- have been singing. Even more so than the patterns and colors of their feathers and the shapes of their bodies, beaks and feet, the songs of birds are what make each species unique.

The variation in how and why birds sing is enormous. Some birds, like the Turkey Vulture or Wood Stork, don’t sing or vocalize much at all. Others, like the aptly named Whip-Poor-Will, repeat a few simple “call notes” endlessly, while some, like the Brown Thrasher, may through learning and improvisation build a repertoire of thousands of different song variations.

Can you hear me now?
Some of the variability in bird song might be explained by the acoustics of different habitats where birds live. The birds are often singing for themselves and one another, so it’s important that their songs be audible to other birds in many cases.

Short, repetitious songs like the “wee-za wee-za wee-za” song of the Black-and-White Warbler, work well for communication in forests. Longer, more complex songs like those of the American Robin or Rose-breasted Grosbeak, carry well across the forest edge. And from the US to South America to Africa many grassland bird songs are buzzy. In the rowdy songscape of tropical forests, where birds must compete for air time with frogs and insects, loud honks and rattles are popular tunes.

Ultimately, however, the big question of why birds sing and what sounds they make can only be (scientifically) answered by studying many different birds in specific times and places and comparing results. Modern technology such as portable tape recorders has done a lot to facilitate this scientific work, enabling researchers to gather songs in the field, analyze them at slower speeds, etc., and even play them back to other living birds to see what happens.

Art and science
Of course, new equipment and new research techniques continually raise new questions about birdsong even as they posit answers to many others. One birdsong researcher whose work has revolutionized the field in a wonderful way is Donald E. Kroodsma, an emeritus professor of biology at the University of Massachusetts at Amherst.

Kroodsma celebrates the magic of birdsong and his own fascinating research over 30 years in his popular book The Singing Life of Birds: The Art and Science of Listening to Birdsong: view link

This book is a must-read for birdsong lovers and one of the best books for birders ever written! It’s not only a fascinating chronicle of Kroodsma’s research, but also offers practical advice on how to learn and appreciate more about birdsong. The book comes with an accompanying CD to further help the learner.

Through a series of engaging stories, The Singing Life of Birds shares how many birds learn (versus innately “know”) their songs, how songs vary from bird to bird, how “dialects” develop within a species in different geographic areas -- and much, much more. Again and again Kroodsma goes beyond mere explanation to awaken our joy and wonder.

But Don Kroodsma is not only a terrific scientist and author -- he’s also a fascinating specimen in his own right! For one thing, he collects bird songs as he tours the continent by bicycle. He biked the whole way across the US in 2003, with recording equipment in tow.

Elizabeth Arnold of National Public Radio (NPR) did a story on Don Kroodsma, which you can listen to here: view link

So what’s to crow about?
Many bird songs and calls seem to be about bird-to-bird communication. Calls might be short, simple messages like “Feed me!” or “I’m over here” or “I see a Cooper’s Hawk!” Songs are often more complex than calls, and in many instances songs are sung only by males and only in the breeding season. These songs seem to be mostly about defending territories and finding mates.

For example, one study found that if a male Black-headed Grosbeak is slow getting back to the nest while out foraging, the female may imitate the sound of a singing male. Her mate, thinking another male is moving in on his territory, is tricked into hustling back to the nest for his turn at egg-sitting!

And then there’s the phenomenon of countersinging, which birders can observe in the field (like maybe among the Chipping Sparrows in your neighborhood?). One male bird sings its song, and another of the same species answers back with the same or a slightly different song. This continues until somebody “wins” and the other stops singing. Who sings longer, or more varied, songs may determine who gets the better territory.

But what about the Saltmarsh Sharp-tailed Sparrow, a bird of eastern salt marshes? The males of this species sing their thin, garbled song for no apparent reason, as they neither defend territories nor concern themselves with attracting females or feeding young. Instead, they flit around the marsh all day in all-male groups (apparently the birds in a “pack” are genetically related) and forcibly mate with females in a unique mating style called “scramble competition polygeny.”

Clearly, we haven’t run out of questions yet when it comes to birdsong!

Do birds just wanna have fun?
Why do birds often sing longest and loudest at dawn? Might it be because the air is cool and still at that time of day, making for better acoustics? Or is it just to let their fellows know that they’re awake and ready for another day? Why do some birds sing for hours even when there are no other birds around to hear them?

Perhaps it’s possible that birds sing just… because they can.

Donald Kroodsma offers us this Zen-like parable: “If you listen to the thrush and hear a thrush, you've not really heard the thrush. But if you listen to a thrush and hear a miracle, then you've heard the thrush.”

Aren’t we birders lucky that we can experience the miracle of birdsong every day?

Peace and good birding,
Scott Cronenweth
Eons birding mentor
www.naturalpathwalks.com