Many birds talk to their eggs and there’s evidence that the eggs hear and respond. For instance, superb fairywrens sing to their eggs and before they hatch the babies sing back!
Now scientists at Deakin University in Australia have discovered that in zebra finches what the eggs hear and how they respond is even more amazing than we knew.
In the last days of incubation, zebra finches (Taeniopygia guttata) sing a special song to their eggs but only when it’s hot outside — greater than 26 degrees C (78.8 degrees F).
The eggs hear the song and it changes their lives.
After they hatch, babies who heard the “hot call” grow more slowly than those who didn’t. Not only are the “hot call” babies smaller as adults but they’re more successful breeders in a hot climate. Surprisingly, this effect extends into later generations.
Small bodies cope better with heat than large ones, so signalling for a smaller size is a great adaptation for a warming climate.
But how does the zebra finch song bring about this result?
Click here to watch the video and read about this amazing feat.
(screenshot from Science Magazine video about zebra finch vocalization. Click on the screenshot to see the video)
This broad-winged hawk was hidden until the songbirds gave him away.
If you hear birds making a ruckus in late August and September, look for what’s upsetting them. It might be a broad-winged hawk (Buteo platypterus) stopping by on migration.
p.s. Broad-winged hawks are forest dwellers, the same bulky shape as red-tailed hawks but smaller and not often seen near people.
This 3-note song mystified me in my own backyard. I can usually identify birds by ear but this one stumped me for at least six weeks.
Finally, I recorded it outside my window and sent it to my friend Dr. Tony Bledsoe. Tony suggested a tufted titmouse. (Turn up your speakers to hear the song in the video above. Ignore the picture, the bird’s not in it.)
A few days later I saw the bird. No wonder we didn’t recognize the song! He’s a gray catbird that sounds nothing like his cohorts. (Turn your speakers back down for the audio below.)
“Grey Catbird (Dumetella carolinensis)” from xeno-canto 318616 by Ted Floyd
Most birds are silent in early July but the odd-sounding gray catbird is still singing in my neighborhood and I can guess why.
None of the lady catbirds like his song so he’s still calling for a mate.
Songbirds are well aware that birds of prey will eat them so they warn each other when they see one. Their warning calls can alert us, too, that a predator is circling overhead.
American robins (Turdus migratorius) stand very still, turn one eye to the sky(*) and make a very thin, high-pitched sound similar to a cedar waxwing’s call. Seet. On the sonogram below it’s shaped like an eyebrow. Here’s what it sounds like:
“American Robin (Turdus migratorius)” from xeno-canto by Paul Driver. Genre: Turdidae.
European starlings (Sturnus vulgaris) make a spitting sound that’s much easier to hear.
They sound off from a safe perch or call “Danger! Danger!” as they take off to avoid the predator. In my experience, they only use this sound when they see danger in the sky. Here’s what it sounds like:
“Common Starling (Sturnus vulgaris)” from xeno-canto by Jarek Matusiak. Genre: Sturnidae.
When you hear these calls, look up to find the hawk. At Schenley Plaza it may be a peregrine falcon.
(*) American robins turn one eye to the sky because they don’t see straight ahead as well as they do side to side. For more information see Anatomy: Field of View.
(photo of American robin by Joel Kluger on Flickr, Creative Commons license. Click on the image to see the original. photo of European starling by Chuck Tague)
Every morning we awake to birdsong now. All the singers are male … right? Well, not really.
When I took a class on birdsong years ago I learned that female birds don’t sing. This information came from centuries of bird observations made in Europe and North America. Charles Darwin even used it to describe how song evolved in male birds to attract mates and compete for territory.
It’s true that almost all the singing birds in North America are male, but there are some exceptions.
Did you know that female northern cardinals (Cardinalis cardinalis) sing and they’re just as good at it as the males?
I was reminded of this last week when a female flew into a tree just over my head and sang a long sustained vibrato even faster than this:
Cardinal couples countersing to synchronize their pair bond. Yesterday in Schenley Park I saw a female sing a phrase several times, then her mate matched it.
So when you hear a cardinal singing, take the time to find the singer. It may be a lady!
For two decades, Chook the superb lyrebird lived at the Adelaide Zoo, South Australia and wowed visitors with his vocal abilities.
Superb lyrebirds (Menura novaehollandiae) are the size of pheasants and native to southeastern Australia. The males are famous for their courtship displays which include shaking their elaborate tails and accurately mimicking a wide variety of sounds.
In the wild, superb lyrebirds mimic natural sounds. In 2009 there was a lot of construction at Adelaide Zoo. When the breeding season came Chook faithfully reproduced the sounds of hammers, power drills and workmen whistling on the job.
Close your eyes at the 3:15 mark and listen to the handsaw!
PEREGRINE FANS, I have no news since Saturday. I will update you when news comes in. Meanwhile, here are links for all Peregrine News to date and Peregrine FAQs (Frequently Asked Questions).
p.s. Thanks to Ed McCord for pointing out this video.
Every year my husband and I spend a relaxing two weeks at Acadia National Park where we enjoy spectacular scenery, wildlife, and hiking trails. Now that we’re heading home I’ll share some of the highlights. The best is a sound that I will certainly miss in Pittsburgh — the haunting call of the loon (Gavia immer).
In September common loons migrate through Canada and Maine from interior lakes to the sea. Each one migrates alone, independent of its mate and offspring.
One particular loon, distinctive because he was molting into winter plumage, often spent his evenings at the harbor. Every morning I heard him make the tremolo call at dawn (click here to hear) but last Wednesday, when the fog came up just after rain, he made a haunting wail call that echoed among the mountains.
Watch the video above to learn what the wail means.
Imagine listening to birds without the sounds of human activity in the background.
In 2012 ecologists from the University of Wisconsin-Madison recreated a soundscape from Aldo Leopold’s time without today’s background noise of vehicles, airplanes, boats, trains and tools.