Birding Through the Year: April 2023

Fox Sparrow. Indian Ridge Marsh, November 13, 2022. Photo by Emily Tallo.

words by David Hoyt

Birds appear to be the most aesthetic of all animals…and they have nearly the same taste
for the beautiful as we have. This is shown by our own enjoyment of the singing of birds.

—Charles Darwin
The Descent of Man (1871)
Chapter XIII,
“Secondary Sexual Characteristics of Birds”

The last six months of birding have been more about what I hear than what I see. When I set out last November to track the owls in my patch, I had little expectation of seeing any of them. I was therefore not disappointed. In a little over half a dozen sorties, I saw only two birds—in silhouette, briefly, and in the dark. But I heard things that I will never forget. Listening to owls added a dimension of depth to my conception of the woods. There is more going on than meets the eye.

Over the long and not-always-frigid winter months that followed, the same woods rattled with the hammering of woodpeckers during the day, sounds carried far in the cold air, making the forest at times seem like the balloon frame of a large edifice under construction.

Even my first experience of spring was a sound before it was a sight. The percussive shock of a woodcock, its wings thrashing in the low brush and against its own body, causes me to jump back in my muck boots. The bird’s effort to become airborne is awkward and belabored, but by the time I recover enough to spot it arcing up through the timber like a poorly punted football, it is almost gone.

The encounter concentrates my senses, and I continue through the forest clearing, pausing at the far edge. I see no more woodcocks, but in the stillness, I hear an unmistakable meep from somewhere in the grass. I mark it as a second woodcok on my checklist, no less satisfied for hearing it rather than seeing it.

Birding is, like much of our internet-influenced culture, overwhelmingly oriented to the visual sense. While I have seen countless people taking pictures of birds with expensive photographic gear, I rarely see anyone equipped to make a serious recording of birdsong. We are capable of capturing both sound and image in startling detail, yet sound seems ephemeral and less valuable, while an image conveys possession. It is no coincidence that early bird photographers saw the camera as a substitute for, and a successor to, the shotgun.

Of course, none of these considerations keep me from marching off to my patch early on an April morning, battered binoculars and second-hand telephoto kit slung over my shoulders, the better to visually discern and, hopefully, photograph whatever I happen to come across. The weather is clear, bright, and cool. Although the air is dry, the river is over the banks, turning portions of the patch into swamp.

I cross a bridge to the lower bank, then break off of the roadside. This zone along a heavily travelled city road is a sort of no-man’s land, thick with invasive shrubs festooned with plastic bags, the ground littered with ancient plastic bottles. For all this, in only a few steps I have the sense of entering into a new place, a different neighborhood, a metropolis of natural, rather than human and commercial relationships.

Bird song is the first sign of this. Robins pass from their shuddering, worrying calls to chipper woodland cadenzas and back again. The noise of Chicago’s grid, never entirely absent, fades to a low basso continuo, a mumbling baseline throb against which the Northern Cardinals resonate like mellow horns from the branches.

Ahead, at eye level, two Fox Sparrows perch, bobbing their rust-colored tails before darting off. A Phoebe, first of the year, flies out and returns to its perch. Smaller shapes dart above, obscure. With the river on the right, I move on through the brush, more open now away from the road. The forest has gently filled with song by now, mostly from unseen vocalists. I sit down on a log and begin to record the soundscape on Merlin.

Unfolding on my device, in rolling sonographic form, is the score of an orchestral performance. It is by turns harmonic and atonal, lyrical and cacophonous. Distinctive sound signatures scroll by, overlapping, repeating, pausing, resuming. There is scarcely a moment unoccupied by avian sound, though not all of it is audible to my unaided ear: varieties of woodpeckers, a flicker, Yellow-rumped Warblers, juncos, supposedly even a kestrel somewhere overhead. In that way that I associated with the most richly “birdy” places I know, the soundscape is immersive.

A new graph appears on the recording. It is a Fox Sparrow, singing heartily. Perhaps it is one of the pair I spotted earlier. It leaves a clear, distinct inscription on my device, and on my ears it leaves no ambiguity. This is a bird singing a song quite close to me, though I can’t hear it. I have never heard this song first-hand. It is curiously thrush-like, of the forest and not the plain, distinctly melodious and lacking the more sparrow-like buzzing and trills. Yet the Fox Sparrow nests in the high arctic, thousands of miles north of our location. I don’t find it included on the Bird Conservation Network’s list of breeding birds of the Chicago region. Why is it singing, and with such gusto, here in the mid-latitudes, in April?

Sonogram of a Fox Sparrow song, recorded in Cook County, Illinois, on April 6, 2023

As I ponder this question, a Winter Wren interrupts me from a nearby bush. It, too, typically winters north of the Chicago region, though not quite so far. It produces a song wildly contrasting to that of the Fox Sparrow, just yards away. If the Sparrow’s sonic signature resembles a sort of calligraphy, with its horizontal emphasis suggesting Arabic, the Winter Wren etches something like Cuneiform, a sprinkle of diamond-shaped notes strung in dangling bands, representations of bits of sound designed to cut through the undergrowth and sonority of wood. I have the impression that the wren is singing an entire octave simultaneously. The sonogram reveals that, while each note is distinct, they are indeed sequenced very, very closely in time. If the Fox Sparrow is singing a soulful folk ballad, the wren is delivering a devilishly challenging violin sonata.

Sonogram of a Winer Wren song, recorded in Cook County, Illinois, on April 6, 2023

Two very different birds, in almost identical habitat, singing very different songs. One is above my head, the other at my feet. Both are invisible to me. The difference between them may be enough to offer the acoustic specialization needed for each bird to safely communicate to its intended audience.

In the days since, I’ve played these recordings back many times. It makes me happy to listen to them, and I wonder why this is. I have yet to find a satisfactory answer. Could it be that there is some quality of joy to be felt in the singing of a bird, for the bird? There are stern evolutionary arguments out there which argue not: the operation of natural selection is far too serious to leave room for such frivolous things as joy in birds. If there is singing going on outside of the northern breeding grounds, there must be a clear evolutionary advantage conferred by doing so. Perhaps it is practice for the mating contests yet to come.

But there are other understandings abroad, including that of Charles Darwin, which propose that the forces of selection are not so strictly utilitarian that they caricature the Victorian morality of Darwin’s own day. In the same chapter of The Descent of Man quoted above, he writes that “nothing is more common than for animals to take pleasure in practicing whatever instinct they follow at other times for real good. How often do we see birds which fly easily, gliding and sailing through the air obviously for pleasure?” Indeed, I see the juncos in my yard appearing to do just this on a daily basis. “The astonishing diversity of birdsong,” writes biologist David George Haskell in Songs Wild and Broken, his book on sonic evolution, "transcends mere utilitarian need to signal vigor…To smile when we hear the tumbling, inchoate songs of birds is not mere sentimentality…The pleasure within us is a reminder of kindship across difference.”