by Ted Floyd
Early last week, we had our coldest weather thus far this fall in the Denver metro region. Monday morning, Nov. 12th, was bright and brilliant—and frigid. I stepped outside around sunup, I looked up, I listened, and there they were: Cackling Geese, skein upon skein of them, hurrying south, saying hink and heenk, but not honk, as they went.
morning long, it continued like that. This was full-on vismig, as the Brits
say. Vismig is Britspeak for “visible migration”—birds actually on the move,
caught in the act of migrating. These weren’t just birds on stopover, feeding
or loafing. These were birds doing
something, going somewhere. This was a full-on phenomenon.
(Left: Photo by Bill Schmoker.)
I love avian phenomena. I love it when I get to see and hear birds doing stuff. The thrill of witnessing natural phenomena is what keeps me going. I’ll be honest with you: I prefer phenomena to rarities. Finding a rarity is, for me, something of an out-of-body experience. The rarity pops into view, a visitor from another dimension, not quite real, more a symbol or cipher than a flesh-and-feathers bird. It gets ticked. In an instant, it is transmogrified. The act of putting a name on a rarity is analogous to the act of detecting a subatomic particle; we see it, and it is altered, forever. The rarity, the actual bird itself, is transformed into a name, a reified name. In the blink of an eye, it is over, it is all over. The bird, the name, has been rendered frozen, lifeless, yet immortal, an entry on a checklist, like an immense probability field of waves and particles suddenly collapsed into a single point in space and time.
Not so with avian phenomena. Avian phenomena keep on going, keep on giving; avian phenomena live on. Indeed, the excitement builds as the phenomenon progresses. With a rarity, however, the whole thing is over, in that instant in which the bird’s name is spoken aloud.
Mixed in with all those Cackling Geese were three Ross’s Geese. Ross’s Geese aren’t hugely rare where I live, but they’re uncommon. Ross’s Goose is a nice bird, something to tell your friends about. Somebody might need it for his county list or her year list. As the geese flew over, I checked for the relevant field marks: small size and short neck; short, stubby bill; no grinning patch. It all added up: Ross’s Goose. Check. Tick. The probability cloud had collapsed. It was over.
But the Cacklers kept on going, streaming south, wonderfully alive, the whole morning. As each skein passed, something inside me intensified. This is it! This is for real! This is happening, right here, right now!
The birds were alive, and so was I, that brilliant morning.
Avian phenomena can be detected anywhere, anytime. Some phenomena are brief, lasting just a few hours. Others run on for several days. Still others extend throughout an entire season of the year—or even longer. An avian phenomenon, it seems to me, has to involve multiple birds. It has to involve birds doing something. And here’s the key: For some phenomenon X, bird xn+1 is even more exciting than bird xn. (Conversely, for some checklist entry Y, bird y1, i.e., the bird, is infinitely more satisfying than birds y2, y3, y4, etc. In fact: yn=∅ for all values of n>1.)
Sorry about that. Geek mode off. Here, without further ado, are a dozen way-cool avian phenomena from my home county of Boulder County, Colorado:
At some point this coming winter, it will get really, really cold. A lot colder than early last week. The temperature will drop well below zero; the next day, the temperature will struggle to reach the teens. The same thing will happen the next day, and the day after that. As a result, all standing water in the northern metro region will freeze over. Except for one place: The water at Valmont Reservoir, heated by Xcel Energy’s Valmont Station plant, will remain open. And when that happens, all the gulls in the region will come to Valmont. Thousands upon thousands of them.
We birders gather at the bluff overlooking Valmont Reservoir, and we watch in wonder as the gulls fly in late in the afternoon, a dozen here, a hundred there, scores here, hundreds more there. The gulls settle on the ice shelf, and then an eagle soars by, and they all put up: thousands of them now, in some winters more than ten thousand of them. There are rarities in the immense gathering, but the most thrilling thing is just the sheer number of Ring-billed Gulls. They wheel about in the still sky, a great snow globe of gulls, as Boulder County guller Bill Schmoker has memorably put it.
Spring is cruel in Colorado. One day it’s sunny and sixty; the next morning, it’s snowing. That’s not a big deal if you’re a seed-crunching grosbeak, a berry-plucking solitaire, or a fish-devouring merganser. But what if you’re an obligate insectivore, a Violet-green Swallow, say? You still have to eat, so you go where the bugs are: immediately above, and even right on, the surface of large lakes and reservoirs.
I have seen tremendous swarms of Violet-green Swallows, all together and all at once, in the twenty feet of airspace above the larger reservoirs in Boulder County. I well remember a morning that quickly went from cloudy to misty to snowy. Mere minutes ahead of the squall, the Violet-greens arrived, more than a thousand of them. For the whole time I was there, they fed frenetically, constantly dipping down onto the water’s surface to glean bugs.
I came back a few hours later, after the sun had come out. There wasn’t a single Violet-green Swallow in sight. The event, the phenomenon, was over, as fleeting as when the morning fog burns off without anybody even noticing.
I’d never heard the term until I moved here: upslope system. Basically, it’s cold, wet weather out of the east, backing up into the foothills. If there’s an upslope system in May, you don’t go to school; you don’t go to work; you don’t do the dishes or feed the kids. You go birding.
(Left: Photo by Bill Schmoker.)
For me, the Clay-colored Sparrow, more than any other species, is the heart and soul of an upslope fallout. On most days in May in Boulder County, your chances of seeing a Clay-colored are about one in ten. During upslope fallouts, however, they’re everywhere. A few years ago, I walked outside the house during an upslope system, and heard Clay-colored Sparrows all over the place. By the time I had walked to the end of the street, I had seen at least twenty. Five hundred feet later, the tally was up to eighty-five.
You don’t plan for an upslope fallout. It just happens. And when it does, you revel in the smart-looking, buzzy-voiced Clay-colored Sparrows, ordinarily uncommon, but so common during upslope systems that you practically have to kick them out of the way.
I’ve blogged about this earlier, so I’ll be brief. By early July, just a couple of weeks past the summer solstice, Chipping Sparrows are migrating by night to their recently discovered molting grounds in eastern Colorado and western Kansas. It is thrilling to go out on hot nights in July and hear the sparrows’ tiny voices calling out in the darkness. My favorite venue is Greenlee Preserve, the postage-stamp preserve down the street from my house. No matter how often I witness the phenomenon, I still find myself saying, “Wow. Chipping Sparrows migrating over by night in the middle of the summer? Who knew!”
Birders mark the passing of time by FOS’s—first-of-season sightings. It occurs to me that the last FOS each year in Boulder County is the American Tree Sparrow. They’re here at the beginning of the year, so there is no spring-migration FOS occurrence for them. Thus, the FOS tree sparrow isn’t until the autumn. The first sightings for me aren’t until well into October, maybe not even until early November—after I’ve scored all other FOS’s for the year.
American Tree Sparrows, like Chipping Sparrows, migrate by night, audibly so. I remember a chilly, misty November night seven years ago. A handful of us were gathered on the north shore of Boulder Reservoir, and we were enthralled by the calls of tree sparrows migrating over in the dark. On their final approach to the big, flat, shimmering surface of the lake, the birds became confused or concerned, and calling intensity increased. We couldn’t see the birds, of course; we could barely see our nearest surroundings, what with the thickening fog. The conditions intensified the experience of being there, the pure experience of being immersed in pure phenomenon.
I’m on a sparrow kick, eh? At least, this one isn’t a Spizella, like the previous three entries. Anyhow. A scant four years ago, the Cassin’s Sparrow would have been a full-on mega in Boulder County. Then, in the summer of 2009, a biological survey turned up a few at the base of the foothills. A few days later, I found a little colony of singing males a few miles to the north. In 2010, county birders found more of them. Then in 2011, they were everywhere. Boulder County super-birder Christian Nunes discovered more than thirty of them, including breeders, that summer. But this past summer, there were just a handful—despite an awful lot of searching.
What’s the deal? Was this just a one-shot incursion, starting in 2009, building in 2010, peaking sharply in 2011, then just as quickly extinguishing in 2012? What will happen in 2013? Will numbers recover to 2010 or maybe even 2011 levels? Or will we back to the old days? I have no idea. Time will tell. That’s the great thing about phenomena. They keep you guessing.
5. Black-chinned Hummingbirds.
Check the Colorado Breeding Bird Atlas, and you will see that there are no records—none at all—of Black-chinned Hummingbirds in eastern Colorado in the Platte River drainage. Black-chins in eastern Colorado, everyone knew a scant few years ago, were birds of the hot, arid Arkansas River drainage. Then something happened. A switch went off. Black-chins suddenly started showing up northeastern Colorado in the summer months.
(Right: Photo by Bill Schmoker.)
Almost immediately, they were found to be nesting. The first Black-chinned Hummingbird I ever saw in Boulder County—in the summer of 2008—was at a nest. Other birders have reported the same thing. In a hummingbird heartbeat, the species has gone from not-on-my-county-list to oh-there’s-another-nest.
Cassin’s Sparrows are notorious for population fluctuations. As I said, I have no idea if they’ll be back in 2013. But I’m counting on ever more Black-chinned Hummingbirds. They seem to be well established and increasing. Which raises the obvious question: Why? What flipped that switch?
Birders love the phenomenon of sheer plenitude, of great throngs of gulls or shearwaters. Even a big flock of blackbirds or starlings, you have to admit, is pretty impressive. How about hummingbirds?
I’m serious. The flock—there is no other word—of Broad-tailed Hummingbirds at Boulder County’s Fawn Brook Inn is awesome. You hear them well before the car eases into the lot across the street. As you walk toward the flowers and feeders, the birds are buzzing all about you. And when you’re actually on the premises, there are so many that you get disoriented. I mean it. You can get vertigo there. I’ve never gone scuba diving and been surrounded by thousands of hyperactive and beautiful little fish, but I think it must be something like the hummingbirds at the Fawn Brook Inn.
Quick! Name some great-sounding birds: Winter Wren, Hermit Thrush, Northern Mockingbird. For sure, they’re all great. Here’s another: the Redhead. The Redhead? Come again? Be with honest with me: How many of you knew the Redhead has anything to say at all?
The call of any particular Redhead isn’t all that impressive. What’s cool, what’s very cool, is when hundreds of males all get together, and all start hooting and whistling. There is something wonderfully forlorn, poignant, and capital-R Romantic about their wailing. I swear, they do it only on cold, raw, still days in early spring. They sound anguished. The effect is overwhelming.
If you’ve never heard the chorusing of male Redheads, go out and listen next spring. Just be sure to bring a hanky.
If you wan to be a better birder, a better observer of nature—heck, just a better human being—then go out and watch robins. Robins are always doing stuff. A single robin is fascinating to observe, but I go for the big flocks. With a flock of robins, there’s never a dull millisecond. Listen to this recording, which I realize a few of you may recall from an earlier post by Yours Truly:
Each year, there is an avian phenomenon that is, without a doubt, the birding event of the year for folks in Boulder County and everywhere else in the Front Range metro corridor. That’s an understatement. The phenomenon is avian, but the experience transcends mere birding. I refer to the southbound passage—vismig, recall—of Lesser Sandhill Cranes.
(Left: Photo by Bill Schmoker.)
I think it’s fair to say that, 99% of the time in Boulder County, you have at best about a 1% chance of seeing or hearing Sandhill Cranes. They’re rare here. Except for when they’re abundant, filling the skies, for an hour or more at a time, with their stentorian bugling. What I love about it is how we have absolutely, utterly no say in how the phenomenon plays out.
Typically, the phenomenon starts around during the lunch hour on a workaday weekday. By mid-afternoon, COBirds is lighting up with reports. I remember the time somebody texted that she was seeing them while driving in rush-hour traffic on I-25 in Denver. I’m not saying I approve of driving, birding, and texting at the same time, but I get it. We stop what we’re doing (or, in the case of our COBirds corresondent, we don't stop!) to watch the cranes. It’s in our genes. We can’t help ourselves. We run inside to tell our non-birding friends to come outside and see and hear these glorious birds.
The phenomenon played out according to script—that is to say, without input from me or any other birder—this past autumn. It happened on a busy Friday afternoon, when I really needed to be doing other things. Like the cranes cared about that.
My favorite experience with cranes was in 2011. That year, they declined to migrate over the Front Range urban corridor. Oh, I’m a sure a few did. But there was no massive overflight involving tens of thousands of cranes, and, oh yes, tens of thousands of admiring humans. I figured I’d missed them for the year. Then something bewitching, and totally unexpected, happened.
My kids and I and several dozen other humans were sledding on a snowy afternoon. It was a noisy, raucous affair, full of laughter and shouting. And then I heard it: the unmistakable bugling of cranes. They came in closer, and the other sledders started to notice. In a moment, everybody was silent, motionless, just watching as the cranes circled above, getting ready to land. All the raucousness, all the laughter and shouting—it was all muted. We just stood there and watched and listened without saying a word. It was a marvelous, a magical, a transcendental moment.
If only for a brief minute, we were all birders.