It’s winter and you’re out for a walk in the neighborhood. As you approach a hedge you can hear it’s alive with hidden birds. They sound like this:
Or this:
The noise is a flock of house sparrows (Passer domesticus) but the hedge is so dense and dark that you can’t see them. The photo below shows the problem; click on it to see the birds in a digitally brightened version.
In the morning and afternoon they disperse to feed, but twice a day — at midday and in the evening — they gather in dense shrubs or evergreens and chatter for an hour or more. If you approach the hedge they suddenly fall silent. If you peer inside you’ll find a few birds looking wary. The rest have flown out the other side.
If you wait long enough, someone else will watch the hedge for you.
(photo of a hedge by decaseconds on Flickr via Creative Commons license; sparrow photos from Wikimedia Commons. Click on the captions to see the originals)
Songbirds are born with the ability to sing but perfect their songs by listening to others. Many learn when immature, usually from their fathers, and then don’t change their tunes. That’s why it was a surprise when Ken Otter and Scott Ramsay discovered that a new song from western Canada is so popular among white-throated sparrows that it’s taking over the country.
Twenty years ago all the birds sang the tune we still hear in the East, “Oh sweet Canada, Canada, Canada.” The end of the song is a triplet of three syllables.
In the early 2000s Otter and Ramsay recorded a new song unique to Prince George, a remote city in northern British Columbia. The birds sang “Oh sweet cana, cana, cana” without the final syllable.
Fast forward 20 years. Otter and Ramsay watched as “Oh sweet cana, cana, cana” moved east and gained traction across Canada. By 2017 the new song was the only one in the west and was sung by half the white-throated sparrows in Ontario.
It spreads during the winter. White-throated sparrows from across Canada spend the winter together in Oklahoma, Arkansas, Kansas and eastern Texas where mature birds demonstrate their favorite tunes.
The new song caught on rapidly with the younger crowd, probably because the ladies prefer it. Who says songbirds can’t change their tunes?
This morning I searched my blog for information on birdsong and was stopped in my tracks by a fascinating article: Male house mice (Mus musculus) sing to woo the ladies.
We don’t realize this because we can’t hear them. Mouse voices are way above our range of hearing but within the hearing range of cats (of course).
Mice sing at a shrill 50 kilohertz (kHz)—and our hearing tops out at just over 20 kHz. Mouse songs might be audible to cats, though, which can hear up to about 65 kHz.
Learn more and watch a male mouse sing in this 2015 article: Mr. Mouse Went A-Courting. (Duke University digitally lowered the audio frequency so we can hear the song.)
(photo from Wikimedia Commons; click on the caption to see the original)
At dusk in July scissor-grinder cicadas (Neotibicen winnemanna) sing from the trees in Pittsburgh. Like birds the male cicadas sing to attract females. Their pulsating drone rises to a crescendo, then drops to a buzz and falls silent. Are they singing in unison? How many are there?
Male scissor-grinders pulse their abdomens as they sing. At close range a single cicada makes a zipper sound. Click here to see another example.
When I’m able to follow the sound I’m often surprised that it’s coming from just one bug who fooled me into thinking a multitude was singing in unison.
Loudness matters. Female scissor-grinder cicadas apparently choose the loudest males.
A single cicada makes a lot of noise.
p.s. Have you heard a different cicada sound in the Pittsburgh area? This article can help you figure out which one: What’s That Sound? Cicadas.
(photo by Kate St. John, embedded videos from YouTube)
Male and female northern cardinals, May 2014 (photos by Cris Hamilton)
When I took a class on birdsong in the 1990’s I learned that only male birds sing, the females do not. Then in 2014 that “fact” was turned upside down. 71% of female songbirds do sing. It’s just that most of them are tropical species.
The original conclusion was drawn from centuries of observations in Europe and North America. No one had studied birdsong worldwide until a team lead by Karan Odom of University of Maryland published their findings in Nature Communications in March 2014.
Perhaps the old-time observers were blinded by their assumption. There are species in North America whose females sing especially in the Cardinalidae family. For instance, northern cardinals (Cardinalis cardinalis) counter-sing and perform duets. Listen for the lady in the background of the recording below (and in this one).
Female blue grosbeaks (Passerina caerulea) sing, too, as recorded by Ted Floyd in Colorado last week.
This is a Blue Grosbeak. Belting out a tune. But it’s not a male.
During #BlackBirdersWeek author, public speaker, photographer and birder Dudley Edmonson tweeted a video birdsong quiz with immediate answers. Click on the screenshot below to listen on Twitter.
How many songs can you identify?
p.s. All five birds are from eastern North America. The yellow warbler pictured above is not on the quiz.
If you don’t hear anything when the Twitter video plays, click the speaker icon on the video at bottom right.
Last evening six of us stood in a dirt parking lot deep in the woods of Washington County and waited for the whip-poor-wills. Twenty minutes after sunset they started to sing.
The eastern whip-poor-will says its name: “whip-poor-WILL, whip-poor-WILL, whip-poor-WILL.” If you’re close enough you can hear the introductory cluck described at Birds Of The World.
Three notes are easily discerned as the bird pronounces its name, and a fourth introductory cluck may be heard at close range.
— Birds Of The World, Cornell Lab of Ornithology
We were that close!
Eastern whip-poor-will, Hillman State Park, 26 May 2020 (recorded by Kate St. John)
When whip-poor-wills nest the female lays two eggs on the ground on top of dry leaves, choosing a place where sunlight makes dappled patterns to match her camouflaged plumage. Hall E. Harrison’s Birds’ Nests Field Guide explains:
Incubating bird sits close; when flushed flies silently away like a moth. Eggs usually discovered by accident rather than by search. Friend of author flushed female from 2 eggs, and returning later to point out nest was unable to find it. After careful study, author detected nearly invisible female incubating 4 ft (1.2 m) away.
— Birds’ Nests Petersen Field Guide by Hall E. Harrison
Since they operate at night even a singing male is hard to find. As we approached our cars to leave, a whip-poor-will sounded very close. Barb Griffith found him in the dark, calling from a flat rock. This photo isn’t the bird we saw, but you get the idea.
Even though birds don’t sing in the winter they still make warning calls so a “cheeping” bird should be easy to find, right? Not necessarily.
Some species, like chickadees and white-breasted nuthatches, make sounds that are easy to pinpoint but the calls of others are thin, faint, high notes that are hard to triangulate. Is the bird up or down? To the left or right? In that thicket or the next one?
Here’s a list of winter birds whose warning or contact calls are hard to find. The calls may be insubstantial, but if you recognize the sound you’ll at least know what species is hiding in the bush. (Turn up your speakers.)
First on the list is the northern cardinal, shown above. I often identify the call but can’t find the bird. Here’s the contact call of a female, one of the hardest to find (around 7000 Hz).
This winter visitor, the white-throated sparrow, has a higher pitched warning call than the song sparrow we hear year round. Listen to the white-throated sparrow’s call (4800-5800 Hz) …
… and compare it to a song sparrow’s (Melospiza melodia) lower pitched “vimp” sound (3500-4200 Hz).
Both sparrows use lower, wider frequency ranges than cardinals so they’re easier to find.
For a really narrow high-pitched frequency you can’t beat the three-note contact call of the golden-crowned kinglet. He’s hard to pinpoint even if you can hear him. Now that I’ve lost my upper range of hearing I rely on friends to tell me when this bird is present. The calls are at 7500-8300 Hertz. Can you hear them? Not I!
Don’t feel bad if you can’t find a bird by its warning or contact call. Even if your hearing is perfect some birds are hiding by voice.
(photos by Cris Hamilton and Steve Gosser, see captions)
American robin, skygazing (photo by Joel Kluger via Flickr)
p.s. Here’s the call of an American robin that means “Danger From The Air.”
In the spring of 2015, Nature On The Go of Green Oak Twp, Michigan found a baby starling fallen from his nest. Since European starlings are invasive, no rehabber would raise the bird for release into the wild, so Nature On The Go decided to raise the starling as an educational ambassador.
As the starling matured he began to mimic phrases he heard from the people around him. For his role as an Animal Ambassador they taught him phrases that explain how starlings arrived in North America. After all, the starlings’ mimicry is an indirect reason why they were brought here.
Watch the video to hear this startling speak. He’s a “Shakespeare bird.”
