The Dawn Chorus
The air is still, the lighting dim, so very dim, on this moonless night. My mind is adrift, adagio cantabile, if you will, as the sky above emerges from true night into astronomical twilight, a period of time when the faintest scatterings of sunlight will now be reflected downward from the upper atmosphere onto our worldly domain. Clear and bright, the stars are visible to the naked eye. The sun, now at 18 degrees below the horizon, incrementally adds a scintilla of light to the atmosphere as it slowly rises.
Once the sun climbs to 12 degrees below the horizon, nautical twilight will begin to dissolve even more of the surrounding darkness. Mariners learned long ago that, weather conditions permitting, there will now be sufficient light to view the horizon, while the brighter stars will still remain visible. This, I discovered, is a moment of magical consequence, as I will explain further into this essay.
You are no doubt wondering what I am doing in the darkness. You might reasonably imagine I’m attempting to determine my location, sextant in hand, by fixing my sights upon the stars or a distant horizon. No, I’m not sailing any one of the Seven Seas, or one of the Great Lakes. I’m not even on a boat.
I’m securely seated in a patio chair overlooking the oak woodland on my property, gazing out onto the southern sky, a mug of hot coffee at my lips. The horizon is blocked by the tree canopy, but above, Sagittarius is in view. I really should still be sleeping, but I have work to do. It is time for a seance with the dawn’s early light.
I’m listening to birds, time mapping the avian soundscape of the night sky around my home in the foothills of the Sierra, south of Yosemite National Park. It’s a challenge. My ability to distinguish one distinct bird vocalization from hundreds (if not thousands) of possibilities is not yet up to the task. I’m working on it, but my deficient hearing compounds the challenge I face.
Fortunately, I’m seated with my trusty friend and birding companion, Merlin. He is an absolute wizard at this task. He can identify birds I can’t see. Better still, he will signal the presence of birds I can’t hear because they are either far away, or their voices are simply drowned out by louder ones. The extent of his knowledge is beyond that of the ordinary person you meet on the street.
If you are wondering who this chap is, I will enlighten you. Those familiar with medieval tales about the court of King Arthur will certainly recall the magical powers of Merlin, a legendary magician. Fast forward now to the 21st Century. A reincarnated Merlin is conjuring up a new form of wizardry on my cell phone, thanks to the electronic sorcery of the Cornell University Lab of Ornithology app, Merlin.
This app is the gateway to a whole new dimension in the discovery and experience of wild birds, Merlin falcons included. The app is free to download to your phone. Merlin will revolutionize your ability to know and hear birds.
It was mid-summer, 2021, that I began an experiment studying bird vocalizations. The searing heat during much of July and August made it unbearable to be under the sun for any length of time. As a substitute for daylight observation of birds, I decided to explore the morning twilight hours when temperatures would be more comfortable. I’ll admit my experiment was a bit of a lark.
During the transition from night into day, I hoped to be serenaded by an enchanting chorale of birdsong as light began to illuminate the hills and hollows of the oak woodlands around me. I did not get far on this track.
To my surprise, and deep disappointment, there was no chorus. In its place, I only heard scattered vocalizations that were devoid of glee: a raven “coughed,” a woodpecker “sneezed,” so to speak. Another utterance, I’m not sure to whom it belonged, seemed to bark: “Not now. I want to sleep in.” The highly vaunted “dawn chorus” I was expecting turned out to be a total bust.
Throughout my tyro attempts at deciphering birdsong in the night, there was, however, one remarkable sound that infused me with a feeling of serenity. Like the voice of an Imam calling the faithful to the first prayers of a new day, so did a distant rooster softly intone a hopeful incantation to the coming dawn. His voice, repetitive and reassuring, resonated across the valley. It seemed to encourage other voices to come forward. But everyone just wanted to sleep in. The rooster paid no mind. He had a job to do. For me, his voice became an indelible auditory celebration throughout my seance in the dawn’s early light. I can hear him now.
In comparison to the emotion-stimulating power of the “Hallelujah Chorus” of Handel’s Messiah, the summertime avian “dawn chorus” I experienced was an absolute dud. So what went went wrong? I realized I was listening during the wrong time of year. The dawn chorus I was seeking to enjoy coincides with annual bird migrations, acquisition and defense of territories, courtship, mating, and prolonged birdsong by males to accomplish those perennial goals. My project would have to wait until springtime.
The following March, I resuscitated my dormant exploration. Temperatures were much cooler than those of summer. Comforted by an outdoor radiant heater I purchased for the purpose, I refocused my efforts at deciphering the riddles of the avian dawn chorus. Basketball championships be darned, March Madness took on a whole new meaning for me.
Know that while sitting on your patio when it is pitch black all around, there is nothing to look at, save the starry skies above; clouds eliminate even that possibility. Without the light of the moon, there are no shadows. Lacking illumination, colors are indistinct. Objects near and far have no visible details. Trees and bushes and all their foliage appear as opaque Rorschach inkblots on the backdrop of the night sky.
One of the challenges for 21st Century humans is erasing all thoughts of the mundane tasks that occupy our day. It is not easy … to just sit there … and listen… That task requires discipline.
Silence is a void that demands to be filled, with whatever pacifier within reach. I told myself that I might as well get some things done while waiting for the birds to sing. I’ll even admit that, the first night on the patio, I cheated and read email on my iPad. It quickly became obvious that would not work out.
The alluring diversions posed by our technological toys are indeed a trap. They are a hinderance to mindfulness. Sitting, waiting in the tenebrosity, absorbing the sounds of dawn’s early light, became a salutary place to be. The darkness, and the mystery of the sounds it held, was a peaceful and enveloping composition that incrementally surrendered its spell to the coming day.
So it was, that in the spring of 2022, with faith in what I was doing, and held steady by curiosity, discipline and patience, I spent several mornings on my patio. Pen and paper in hand, I time mapped the sounds of the birds around me, from the darkness of night until the sunlight of each new day. In so doing, I opened a door to knowledge not readily found in books.
As sweet and savory the taste of enlightenment was, I wasn’t satisfied. This initial experiment ending up being a teaser. I aspired for more. To that end, I re-embarked upon my auditory voyage of discovery during the spring of 2023, and again in 2024. I dedicated several mornings to the twilight skies in order to: 1) build upon what I had learned, 2) confirm what I thought I had learned, and 3) this time, have fun. Revelations to follow.
Civil dawn is a moment in time that occurs when the sun has risen to six degrees below the horizon; the civil twilight that ensues ends with sunrise. In contrast with nautical and astronautical twilight, civil twilight is distinguished by sufficient natural light for people to safely perform outdoor activities.
The tenebrosity of astronautical and nautical twilight having faded away, tonal gradations now come into view; there are highlights and shadows. Colors emerge in our surrounding landscape. We can now make out the details of the leaves and the bark on the trees.
What about birds? Is civil twilight meaningful to them? Yes, of course, but so are nautical twilight and astronautical twilight. These morning twilights are triggers that affect birds in different ways, depending upon the species and the time of year. And not in ways that you might expect. For example, birds migrate at night, as if following a compass heading in the earth’s magnetic core. They still might collide with objects in the dark.
I could not help but wonder, are there really very many birds flying around throughout the night? Thanks to technological development and interpretation of weather surveillance radar, you can read daily reports of nightly bird migration activity across the United States published by BirdCast (https://dashboard.birdcast.info/). I was astounded to learn, for example, that during the night of April 21, 2024, 1,880,900 birds crossed Madera County, Ca. where I live. You can find similar information for where you live, too.
When I opened the door to my first dawn chorus in 2022, I was as ignorant as a vestal virgin with regard to birdsong. The world at that time was in full Covid-19 lockdown. Any relief from the fear of contagion was welcome. I embraced the opportunity to learn about birds with open arms, and ears.
The stillness of the night never lasts for very long. If you are awake, most any sound will arouse your senses: occasional dogs barking, vehicular traffic, wind in the trees, voices from neighboring dwellings, coyotes, and roosters, too.
Unsurprisingly, nighttime belongs to my neighborhood Great-horned Owl who hoots intermittently throughout night, as well as during the subsequent twilight hours: Hoo-hoo-hoo. No surprise there: I already knew that voice from my residency in New Mexico, and wrote about it here.
(Note: turn your volume up to listen to the following recordings).
Great-horned Owl in flight
Thanks to Merlin, though, I now discovered the call of an unseen female when she vocalized. I had heard this sound on other occasions, but never could identify it, so soft and different it was in texture than anything else I’ve ever heard.
Suddenly, a motion detector turned on, illuminating a fenced area adjacent to where I was seated. I heard no movement, and I saw nothing, but I knew she was now on the roof above me. After sunrise, I noticed a white stain dripping down the fence siding; that had been her perch, only thirty feet away.
A seasonal stream runs through my property. Winter and spring rains mean there is a lot of water soaking into the ground, frogs are croaking, and grasses growing. It is very moist environment along that stream bed, such that I always wear boots when I walk along its banks. That habitat is a breeding ground for insects, and spring is their release from winter’s chill.
I’ve often wondered why we don’t have a mosquito or other flying insect problem around my home. Thanks for that belongs to Violet-green Swallows who are in residence this time of year.
Like a squadron of Star Wars space invaders, they swarm the air above and below, in and out, gliding all around the tree canopy beginning in the earliest minutes of astronomical twilight (maybe even during true night, but you won’t likely find me outside during the middle of the night). The buzz of the swallow’s dawn song continues uninterrupted into the daylight hours; and throughout much of the morning as well, as long as there are insects in the air. Evidently, there are a lot of insects flying around my property. I often wonder if there are every any collisions.
Violet-green Swallow
Sitting at the patio table with my friend, Merlin, sipping coffee, I sometimes become so accustomed to the sound (almost like white noise), that I forget the swallows are present. I have to remind myself to chart their activity as well as that of all the new voices that are now joining the chorus. I say to myself, “Mark it down: astronomical twilight belongs to the swallows, bless their throaty voices.”
Towards the end of astronautical twilight, Western Bluebirds and Western Kingbirds make their presence known. Their vocalizations are tentative and brief, random it seems. They are not flying, as best I can tell; their sounds emanate from a static location, at least for now.
The sound spectrum changes dramatically as nautical twilight begins to brighten the sky. Several chatty oak woodland species also make their presence known during this time (I’ve included a catalogue below), but nautical twilight belongs to the bluebirds and kingbirds.
Western Bluebird eating worm
The soundtrack develops as follows: bluebirds invariably start the show. Their cheerful-sounding cadences are always uplifting; I can’t help but smile all the while they can be heard.
But wait, not so fast, my mellifluous, sweet-toned bluebirds. Unwilling to be outdone, the kingbirds soon chime in.
Western Kingbird in flight
As softly and as gracefully that the bluebirds tell their story, in contrast so does the boisterous and proud kingbird dawn song take center stage. Over and over, the same syllables mark time on the avian soundscape. If repetition, hoping for a different result, is the definition of insanity, the kingbirds have it in spades. To me, their vociferations sound like the sputtering of a garden hose. Their voices always make me laugh, and I love them so. They are here for only a few months, building nests, before they continue their migratory journey.
For the next half hour, like dueling banjos, the vocalizations of these two songbird species will remain sustained across the soundscape, with no interruptions.
The march of time moves forward at its inexorable pace, and the sky brightens ever-so with each passing minute. Bluebird voices fade away; kingbirds, now reigning over the soundscape, continue their act into a new twilight phase, during which they, in turn, will relinquish the stage to the birds of civil twilight.
I mentioned this birdsong phenomenon so often to one of my hiking companions that he, too, rose before the crack of dawn to listen to the avian chorus of his night sky about 30 miles away. His auditory experience was similar to mine: first the bluebirds, then the kingbirds, every morning at the same time as my birds.
This same friend owns a two seater airplane that he sometimes flies during the pre-sunrise darkness. When I told him about BirdCast, and all the birds that are in the air during those same hours, he stuttered: “I better start paying more attention. That is the altitude at which I fly.”
As the mornings passed, my confidence grew in step with the knowledge I acquired. Through the efforts of my very early morning embarkations, I had gained entry into the dawn chorus temple of knowledge. No longer a birdsong nestling, I fledged and joined the ranks of birdsong insiders. I knew facts that very few people could ever imagine. And now you know some of my secrets, too.
To facilitate tracking of the avian soundscape, I created a spreadsheet at the top of which there is a horizontal, alphabetical list including twenty three species that I’ve come to expect to hear, with an additional column to note anomalies, vagrants, migrants (of the feathered kind, of course) whenever they appear. I note the time in the leftmost vertical column that descends with the passage of time.
I also use symbols to indicate whether a sound is a simple tweet, a multiple syllable series call, or a vocalization sustained over a longer period of time. In this manner, I can easily visualize which birds are vocalizing (or should I perhaps say “socializing?), for how long, and during which twilight phase.
Oak titmouse
Once civil twilight begins, I find the Oak Titmouse to be the dominate voice, not only for its loudness (proximity to me?), but also because of the variability and frequency of its vocalizations. The titmouse has lots of competition, though: Acorn Woodpecker, Ash-throated Flycatcher, California Scrub Jay, White-breasted Nuthatch, House Finch, House Wren, sparrows, doves, European Starlings, and so many more, all of whom play their notes as directed by an unseen evolutionary conductor.
Postscript:
Do try this at home, not on a boat. Yes, you can. Your results will most certainly vary from mine. Every day that you wait to start means that you will have to rise about one minute earlier. The days get longer, after all, on both ends of the day, so twilight not only ends later in the morning, it likewise begins earlier, too. Get started. The clock is ticking.
Trust me on this: follow the timeline, from the darkness of night, through astronomical, nautical, and civil twilights into the the unequivocal brightness of day, and you will experience fifty shades of gray in a way that you never could have imagined.
Good luck. May the dawn chorus be with you.
The following catalogue includes (in alphabetical order):
A) the wild bird species (permanent and seasonal residents) that made their presence known during various phases of twilight. Italics indicates a principal voice.
B) a sub-list of species who may have “tweeted” briefly on a single occasion while passing through.
Astronomical Twilight:
A) Barn Owl, Great-horned Owl, Violet-green Swallow
B) Red Crossbill
Nautical Twilight:
A) Anna’s Hummingbird, American Robin, Black Phoebe, Bullock’s Oriole, Canada Goose, Cedar Waxwing, Common Raven, Great-horned Owl, House Sparrow, Killdeer, Mallard, Red-shouldered Hawk, Western Bluebird, Western Kingbird, Violet-green Swallow
B) Barred Owl, Cassin’s Finch, Northern Saw-whet Owl, Pine Finch, Pine Grosbeak, Purple Finch, Rock Pigeon
Civil Twilight:
A) Acorn Woodpecker, American Goldfinch, Anna’s Hummingbird, Ash-throated Flycatcher, Bewick’s Wren, Black-headed Grosbeak, Black Phoebe, Bushtit, California Scrub-Jay, California Quail, Canada Goose, Common Raven, European Starling, House Finch, House Sparrow, House Wren, Lesser Goldfinch, Mourning Dove, Northern Mockingbird, Oak Titmouse, Phainopepla, Red-shouldered Hawk, Golden-crowned Sparrow, White-crowned Sparrow
B) Dark-eyed Junco, Great Blue Heron, Great Egret, Red-winged Blackbird, Ruby-crowned Kinglet, Song Sparrow, Vesper Sparrow, Western Vireo, White-throated Sparrow
Daylight:
A) Bullock’s Oriole, Canada goose, Eurasian Collared-Dove, European Starling, House Sparrow, House Wren, Lesser Goldfinch, Mallard, White-breasted Nuthatch, Song Sparrow, Violet-green Swallow, Yellow-rumped Warbler
B) Herman’s Flycatcher, Pacific Slope Flycatcher, Nashville Warbler, Wilson’s Warbler, Yellow Warbler
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