I'm sure you've seen starlings fly away to avoid a predator. Have you heard their warning signal?
Over the years I've noticed that European starlings (Sturnus vulgaris) make a spitting sound just before they flee. Sometimes only one or two birds call the alarm, a sharp note repeated three or more times. It sounds like this.
When I look for the reason they're making the sound, I always see a hawk in the air. I've learned to look for a raptor when I hear that sound.
The starlings must be saying, "Danger From The Air!"
(photo of starling flock by Pat Gaines on Flickr; click on the image to see the original. Recording of common starling (Sturnus vulgaris) by Toon Jansen at xeno-canto #XC393749)
Birds use alarm calls to warn each other of danger but pigeons are generally silent. What sound could a pigeon make to signal danger? The crested pigeon (Ocyphaps lophotes) of Australia uses his 8th feather.
Crested pigeons make a whistling sound when they fly -- a high note on the down stroke, a low note going up. Researchers found out that the eighth primary feather is the source of the high note and that the speed of the low-high modulation provides the warning.
When a bird flaps slowly the whistle repeats slowly, so other pigeons decide the bird is not afraid. When the sound repeats rapidly it sounds like the pigeon is fleeing, so the other birds do, too.
This fall migrating mockingbirds came back to town to spend the winter.
Northern mockingbirds (Mimus polyglottos) were a southern species that now nest as far north as southern Canada. In autumn the birds move south and some decide that Pittsburgh is as far as they need to go. New arrivals immediately set up territory and warn off other mockingbirds by singing, "Mine, Mine, Mine."
The songs are pretty, and pretty confusing because mockingbirds mimic other species. For instance, this Xeno Canto recording by Joshua Stevenson has an American robin sound at 0:11. No it's not a robin.
When I walk around my neighborhood this month I hear 15 different songs but they come from only two locations. Two mockingbirds are "dueling" from opposite sides of Magee Field, the only birds singing in November.
What's that sound? In July the birds stop singing and the bugs begin. Some sing during the day, others at night. We usually don't see what's making the noise but sometimes we can identify the bugs by song. Here's a group of insects that are fairly easy to figure out.
Cicadas sing during the day and they are loud. Some songs are so unique that you can identify the bug if you know what to listen for.
Here are audio descriptions for five common species of annual(*) cicadas in southwestern Pennsylvania in order of "most likely to hear/notice," at least in my experience.
As with birds, pay attention to the habitat where you hear a cicada. Swamp cicadas, for example, are only found in swamps or marshes.
Scissor grinder cicada (Neotibicen pruinosus). Easiest sound to identify.
Song: a repetitive WEEE ah, WEEE ah, WEEE ah, WEEE ah, tapers at end
When? may begin in late morning, but sings the most at dusk
p.s. Annual(*) cicadas have a life cycle of 2-5 years but they seem "annual" because some individuals in each species reach adulthood every year (i.e. the species appears annually).
p.p.s There aren't many scissor-grinders in my neighborhood this year. I wonder if they had a bad reproductive year the last time this brood was above ground. How long do scissor-grinders take to reach adulthood? If it's 5 years then that'd be 2012, a very hot year. Hmmm.
I used to think that the wood thrush had the best song of all North American birds until I stood on a trail in north central Michigan this week surrounded by singing hermit thrushes. What a privilege to hear them!
If you've never experienced their ethereal song, don't put off the experience for two decades as I did. Hermit thrushes (Catharus guttatus) nest on the ground in coniferous or mixed northern forests. As our climate warms their preferred habitat will be disappear from the eastern U.S. By 2050 their eastern breeding range will move north into Canada at Hudson Bay.
There's a small brown bird at the feeder and there's no one to help you identify it.
Don't you wish you had a personal assistant to help you?
Cornell Lab of Ornithology's free Merlin Bird ID app for Android and iPhone does just that. Introduced in 2014, the app gets smarter every year. It uses the simple information you already know -- your location, the date and the words "small," "brown," and "at the bird feeder" -- to narrow your choices and identify the bird.
You can even take a picture with your cellphone and ask Merlin what it is.
Merlin's answer is a list of the most likely suspects with photos, sounds and descriptions. It even tells you if the bird is uncommon or rare for your date and location. That's one of the best clues you'll find anywhere because an "uncommon" species in March can become "common" in May.