American Birding Podcast



How to Record Birdsong—Part 3

Note: This is the third in a three-part series on how to record bird vocalizations. We looked in Part 1 at which hardware to use and how to use it. In Part 2, we learned about software. In this third and final installment, we take a take a broader view—what to listen for when we’re actually out in the field with our recording gear.


2. Hear the bird.
 Human ears are great at hearing birds. The problem is when our brains get involved. Our amazing brains have this annoying way of hearing what we want to hear. We all know about that in human relationships. It also affects how we hear birds.

In a nutshell, our brains are splendid filters. We’re focused on the song of a Virginia’s Warbler, and our brain blocks out all the stuff we’re not interested in: footsteps, an airplane overhead, and other sounds like Canyon Wrens and Cordilleran Flycatchers. Our brains also have this off/on switch when it comes to ID by voice: Within a certain radius of detectability, we hear and recognize the bird; beyond that radius, we do not. (Years ago, I read a scientific paper about this.) So, whether our hypothetical Virginia’s Warbler is nearly 500 feet away or just 50 feet away, we hear it as basically the same sound—even though the spectrogram sure disagrees with that assessment!

Enough of our hypothetical Virginia’s Warbler. Let’s listen now to a real Virginia’s Warbler, one I recorded in the foothills of Boulder County, Colorado, back on June 5 of this year. I was nearly 500 feet away when I first recorded the bird. Here’s the recording:

I got closer, which you can surmise by the sound of an annoying footstep (mine), right smack dab in the middle of the bird’s song:

I’m closer still now, but now the Virginia Warbler’s singing is interrupted at the beginning by a Cordilleran Flycatcher and cut off at the end by a Canyon Wren (and the flycatcher again):

We have a new problem now. I’m gotten yet closer, but there’s an airplane going over. It’s that low-frequency droning sound. For sure, the Audacity High Pass Filter would be a good idea right about now. But let’s not. Just to make the point, let’s listen to a nice Virginia’s Warbler and an annoying airplane:

Finally, at a distance of about 50 feet, I got this clean, clear recording:

I assume you’ll agree that those five recordings differ appreciably in quality. But here’s the funny thing: In the field, I didn’t really pick up on the differences. The bird sounded as much like a Virginia’s Warbler at 500 feet as at 50 feet; my brain shut out my footsteps and the airplane; and the flycatcher and wren seemed strangely faint and distant, despite what the recording tells us.

I’ve gotten to the point now where I make a mental checklist of all the things that diminish the quality of a recording: wind and water; plains, trains, and automobiles; footsteps; western chorus frogs; House Wrens; and Canada Geese. It’s the same way with photographers and their eternal struggle with backlighting, light angle, shadow, branches, buildings, etc. When we’re in the field, our brains conveniently adjust for those things; when we review the images onscreen, those features become inconveniently prominent.

Something else: distance. A bird at 10 feet is going to look better photographed with a smartphone than through a high-end telephoto lens at 1,000 feet. Analogously, that Virginia’s Warbler sounds better at 500 feet than at 50. So get close to the bird. Be stealthy. Move slowly. Try not to disturb the bird. As always, abide by the ABA Code of Birding Ethics when pointing a camera or a recorder at a bird.


7. Enjoy the show. Let’s wrap up now by having some fun. Here’s a sampler of recordings, all made with the Olympus LS-10. All are from Colorado, May–June 2014.

 Back on May 17, Dan Durda and I saw a “Traill’s Flycatcher” at Greenlee Preserve, Boulder County. It had the visual characters of an Alder Flycatcher (thin eye-ring, greenish overall), so we had a hunch it was this species—rare anywhere in Colorado. I heard a single peep note, fairly distinct from the Willow Flycatcher’s low, whit. But the bird wasn’t giving us much on the auditory front. Dan had a birdsong app with him, and played a brief snippet of Alder Flycatcher. Check out the result:


Not nearly as rare in Colorado as the Alder Flycatcher, but still a nice bird, is the Red-eyed Vireo. Especially when you hear one in plausible breeding habitat in late June. There are amazingly few confirmed breeding records of the species in the state. With young birder Topiltzin Martínez and my kids Hannah and Andrew, I recorded this Red-eyed Vireo, singing his heart out, in a dense broadleaf grove along South Boulder Creek, Boulder County, June 21:


7.2–Tricksters, Mysteries, and Challenges. The Red-eyed Vireo we just heard was totally unambiguous. But Topiltzin and Hannah and Andrew and I heard some less-straightforward birds that long day of summer solstice birding. For example, this “Rufous-sided Towhee”:


Hmm… Sure sounds like the Eastern Towhee’s Drink Your Te-e-e-ea! But I’m not convinced. We got only the briefest of glimpses of the bird—only enough to confirm that it was a “Rufous-sided Towhee” of some sort. The Eastern Towhee is exceedingly rare in Colorado. And, although the song resembles the Eastern Towhee’s, it’s not classic for that species, either. Maybe this is a Spotted Towhee or a hybrid from the contact zone between the two towhees? Maybe it learned the song of an Eastern Towhee, but not quite perfectly?

Toward the end of the day, as we were approaching Rabbit Mountain, Hannah had an insight: “This looks like a good place for a roadrunner.” There are no records for the county, but she’s right: The south slope of Rabbit Mountain—with its rocks, spiny plants, and rattlesnakes—seems ideal for a species that may well show up here some day. No roadrunners for us today, but check out this bird:

Curve-billed Thrasher? That would be a “mega”—a very rare bird—in Boulder County. Perfect habitat. Curve-billed Thrashers and Greater Roadrunners co-occur in the cholla-and-yucca–studded landscapes of southeastern Colorado. But I’m nearly certain our bird wasn’t a Curve-billed Thrasher. This bird was, in all likelihood, a Yellow-breasted Chat. I didn’t actually see the chat open its mouth and make these sounds, but the call came from the immediate vicinity of the chat, and chats are skilled, if under-appreciated, mimics.


7.3–Science. I’m working now on two contributions to Colorado Field Ornithologists (CFO). One is a paper to appear in CFO’s quarterly journal Colorado Birds; the other is a scientific presentation at CFO’s annual meeting a bit later this summer.

For the paper in Colorado Birds, I’m looking at the stronger-than-usual mid-May 2014 flight along the Platte River I-25 corridor (Casper, Wyoming to Denver, Colorado) of Gray Flycatchers, Northern Waterthrushes, and Clay-colored Sparrows. I’m getting the basic data from eBird, but I also need some audio-visual support. Unfortunately, those three species aren’t all that photogenic to begin with, plus they occurred during a weather system that was horrific for photography. So how about some audio? Here are some recordings from Boulder County, all during a strong “upslope” system the week of May 11—a Northern Waterthrush (with warm-up from a Yellow Warbler), followed by an actually singing Gray Flycatcher (first time I’d ever heard one singing on migration in eastern Colorado), followed by a whole chorus of singing Clay-colored Sparrows:




For the presentation at the CFO meeting, I’ll be reporting on four years’ worth of audio-recording of Warbling Vireos east of the continental divide in Colorado and Wyoming. “Western” Warbling Vireos occur chiefly in the mountains and foothills, as you might expect, whereas “Eastern” Warbling Vireos occupy broadleaf groves along creeks and rivers on the Eastern Plains. But what about areas of overlap? Barr Lake State Park, near Denver International Airport, seems to be one such place. Check out these two recordings I made there on July 2, first an apparent “Eastern” Warbling Vireo, then, less than a half-mile away, an apparent Western Warbling-Vireo:




7.4–Beautiful birds. Let’s not lose sight of a point I tried to get across at the very outset. With a decent pocket recorder, good ambient conditions (no wind, no cars, no Canada Geese), and a bit of Audacity-based editing, you can get some great recordings. Here are two samples. First, this Green-tailed Towhee in Rocky Mountain National Park, Larimer County, on June 7:

What’s cool about this bird’s song is how it changes from one phrase to another. Phrases 1 and 5 are of one sort, phrases 2 and 3 of another, and phrase 4 of yet another. Don Kroodsma wrote a whole book about this sort of thing, and I gather Nathan Pieplow has a major new book coming out too.

Towhees and other sparrows sing complex songs. Flycatchers’ songs average simpler, but no less beautiful. Here’s the simple and evocative song of an Olive-sided Flycatcher, singing at dawn at the Walker Ranch, Boulder County, June 21:


7.5–Beyond birdsong. One of the most poignant lives ever lived was Ludwig van Beethoven’s. In his late years, the composer was nearly completely deaf. He couldn’t hear the music the way we do. Paradoxically, Beethoven’s art is generally believed to have been assisted by deafness: Beethoven was unshackled from the constraints of normal human hearing, set free to explore the world of pure sound. The result was some of the most enduring and imaginative art of all time: the Diabelli Variations and Missa Solmenis; the achingly beautiful late piano sonatas; the immortal Symphony No. 9; the berserk yet bewitching Great Fugue; and the late string quartets—in some people’s view, the summit of all music-making,

I don’t aspire to achieving the ability to hear Beethoven’s music only in my head. To be honest with you, I don’t spend a lot of time these days with the scores. I’m content to a “mere” auditory experience. (Although that YouTube video of the score, above, is very cool, and I hope you’ll give it a click.) But I don’t feel that way, these days, about birdsong.

One of my all-time favorite natural sounds is the melancholy song of the Cassin’s Sparrow. During that field excursion in late May 2014 to Las Animas County, Colorado, my companions and I heard a few of these brown desert birds. Our objective wasn’t really Cassin’s Sparrows, as we were concentrating more on the birds of the canyon country. But we needed—really, it was an emotional and psychological need—to hear Cassin’s Sparrows. So, on the last day, we got into higher and drier terrain, and heard a few. Let’s listen to one of them:

33-Cassin's Sparrow waveform and spectrogram

Don’t bother clicking on the image. There’s no sound file with this one. It’s lovely, isn’t it?