Foreign Bird Call

Thrushes are our most accomplished singers around here. Their songs are complex, variable, extremely melodic, and endlessly fascinating. The three thrushes we have, in decreasing order of song beauty are the wood thrush, Louisiana water thrush, and the good ol’ American robin. Thrushes are also migrating birds, so we eagerly await their calls each spring and joyfully exclaim our first hearing. 

For years, we’ve thrilled to listen to our best thrush caller—the wood thrush—coming from various places off in the woods. They are the first to call just before dawn and again the last to call after sunset. Their song is a three-part symphony, always repeated in the same order: (1) two low stutter tones, (2) followed by three flute-like liquid notes in varying order, and (3) capped off by a high-frequency trill or tremolo. The third part comes in at least half a dozen varieties, and the bird delightfully mixes them up. I can listen to a wood thrush call out 20-30 times and he never exactly repeats his song.

This year was different, however. There seemed to be only one thrush out there in the woods, and his song was not the same as in the past. Most of the time this guy left off the first and third movements—curtailing it to singing the middle three notes. At other times he’d just sing the final trill. I don’t think it was the same bird we’ve had on the past… moreover, it was only one bird calling from out in the woods during the season. Where were the other thrushes this year? Was this a new guy—either from another territory (with another accent) or maybe a juvenile just learning the song?

Ornithologists know that America’s wood thrush population is alarmingly declining. They breed in the eastern United States and winter in Central America. In both regions, their habitat is disappearing, as forests (its only home) are cut for agriculture and other commercial uses. We feel very fortunate to have had a viable population of wood thrushes around here, these last several years. But maybe they’re dwindling and we’re hearing the last of them now? This year’s lone caller was unsettling. It’s just a matter of time before we will no longer be thrilled by their wonderful song.

I wonder if this year’s single thrush’s different song is because he’s not one of our local birds, but one who has moved in from someplace else. Birds develop regional accents in their calls—especially if they tend to hang around the same location. They learn the local dialect and stick with it. But if a juvenile doesn’t get exposed to its species’ normal song, it’ll develop its own distinctive—and very much simpler—song.

So this lone caller could be a lonely juvenile who did not have mentors around to teach him. Or he could be from another region, and has moved into our territory—either because his native habitat has disappeared, or even that climate warming has driven him a little north this year. (Maybe that’s a Georgia accent I’m hearing?)

We also had fewer Louisiana water thrushes calling out this year, and the calls we did hear were also a little different from the past. So I wonder if we may be experiencing the same thing with both kinds of thrushes: a decrease in population and a subsequent change in calls. I hope not.

When the number of birds declines in an area, the lesser-skilled or less aggressive males begin to predominate for a while. In a normal situation, the best singers prevail, causing the poorer singers to slink off and lose their chance to mate. In any given year, most of the birds who could mate, do not do so, because they get shoved to the margins. But as the population drops off, the less talented (and maybe less fit and healthy) birds get their chance. Maybe that’s what’s going on here?

I can only guess how lonely it must feel to a bird, as the population declines and they find mates increasingly scarce. At first, maybe the less fit birds would flourish, because they have a chance to claim territory they’d otherwise be pushed out of. But as time goes by and the population further decreases, even those who persevere can’t find mates. What’s it like, for those last few birds, as they search in vain? How does the last bird feel? Does he or she sense something wrong?

After a few weeks of the strange-calling wood thrush singing out with his truncated song, we no longer heard him at all. Did he fail to attract a mate? Did the local females reject his call as being just too foreign? Did he move on to yet newer territory, seeking better luck? Later, we heard a few hesitant wood thrush calls far off… too far off to discern which bird it might be.

I pray that this year was just a weird experience, and we may once again hear that old, thrilling call next spring. At some point, however, we (or our survivors) will hear the last thrush call. The termination of a natural phenomenon that’s continued for hundreds of thousands or even millions of years is very sad.

New Bird Call?

A few months ago I was soaking in the tub when I heard what appeared to be a new bird call for me. Over the years, I’ve been able to identify most all of the calls of our local avian residents, and even a few who are traveling through. It’s neat to get to know the calls, so when I hear one sound off in the woods where I can’t see him, I can imagine who the caller is and what he looks like.

But this call was a new one for me. The bird was just out of sight, so there was no chance of spotting him, without stepping out of the tub… a move I’m extremely reluctant to make, after I get soakingly settled. I was curious about this call, but not that curious.

The call had two parts to it, it was very simple: a kind of trilly “brrr,” followed by a higher pitched whistle. Over and over he called, as the mystery deepened. What kind of bird was it? I closed my eyes, as if that might help me guess. He continued to mystify me.

Then suddenly the caller landed on a branch just above my head, continuing to sing. I opened my eyes and saw it was a common chickadee… just a little ol’ chickadee. I’ve never heard them sing like this! In fact, there were three of them, cavorting around, each one in turn calling out.

It was if they were demonstrating for me: “Look! Here’s our new song that we just learned. How ‘bout that? Yes, it’s us, your chickadee buddies. We’re not singing for territory or mates, just goofing off and seeing what we can do. Don’t you know it’s almost a full moon? We’re gonna have a party!” With that, they gaily flew off, still belting out their new song.

One more lesson for the giant, water-logged, two-legged, non-flying creature. It’s nice to know that the local critters are kind enough to keep teaching me. There is so much to learn from them.

Farm Sitting

Am spending the week farm sitting for friends in the Allegheney Mountains.

Awesome Exhibition

At certain times I get treated to a phenomenon when I’m outdoors that is simultaneously exciting and intimidating. It’s exciting because I sense, in the deepest core of my being, some approaching event that prickles the back of my neck. The air seems to crackle with nascent energy. Something fascinating is about to happen! It’s also intimidating for many of the same reasons: the atmosphere is pregnant with the expectation that something awesome is about to transpire, and it just may even be harmful.

The first sign of this particular phenomenon is a subtle but dramatic transformation in my aural environment. Mother Nature’s background soundscape has been running along, continuously and calmly, lulling me into a relaxed state, with ambient sounds flowing gently through my mind. It’s so constant and soothing that I hardly notice it.

But then a change abruptly but subtly occurs. Something different is impending. The repetitive wave of aural activities that has been flowing along—the wafting of the wind, the twitter of birds, the chatter of insects—ceases. The abrupt termination of these sounds is what first captures my attention. What is going on? What do the little critters sense, that I don’t? A hush prevails, followed by a quiet, steady, distant whooshing sound, that is much more even and constant than what was happening before. It’s as if someone had clicked on a high-powered fan, far off in the woods.

It’s very unwavering, as it drones through the trees, and seems to be coming towards me, ever so slowly and relentlessly. Nature’s usual sounds fluctuate, and my ear becomes familiarized by that variation. This new sound seizes my attention; if only because of its stark and almost ominous steadiness. Is this why the critters silenced themselves?

Hmmm… is this really a natural event coming my way? Could it be wind? Or is it manmade? An airplane, maybe? Then I notice that it gradually and relentlessly is growing louder. Hmmm… that’s when the intimidating part begins to tickle the back of my neck. The sound seems powerful and unfaltering, as it relentlessly marches my way. Should I be scared? Is something far more powerful than I about to invade? Transfixed, and with no idea of how to take evasion, I await its coming.

Then, just a moment before it strikes, I finally realize that it’s an advancing wall of rain. What I’ve been hearing is the white noise of jillions of raindrops splashing on tree leaves; relentlessly coming ever closer. Then I abruptly become engulfed in the rain. The delightful—and even comforting—sound of nature’s cleansing and renewing process surrounds me.

Had the rain been preceded by thunder and wind, I’d have instantly known what was approaching. There were none of these warning sounds this time, however—just the steady sound of the approaching wall of water. I’m relieved that it’s not an alien spaceship from far out in the galaxy… it’s just another blessing from Mother Nature.

Grape Leaf Folder Moth

 

These guys fold over a grape leaf, stitch it up, and hide inside, to eat in peace.

Melodious Drummer

I was sitting in the outdoor tub, enveloped by the quiet night, waiting to listen to the next interesting sound that sauntered my way. Dusk was descending. I was not able to see much detail anymore, but still able to hear numerous aural particulars. I was drifting along with the flow of mundane events.

A sound came to me: the drumming of a woodpecker. But this one was no pedestrian drummer. He was a virtuoso. A woodpecker’s usual drumming sound is loud and repetitive—emanating from a hollow tree branch that he has claimed as his very own. It rings out through the forest, as if the bird has proudly discovered a wonderful new drum to beat on; sending his exuberant message to all, but especially to any receptive female woodpeckers who may be within hearing distance.

Woodpeckers come in several flavors around here: downy, hairy, red-bellied, and pileated—from small to large. In addition to being garish drummers, they are also garish in their appearance. They flaunt their contrasting black and white apparel, like a teenage boy dressed up for the prom. Their woodpecker tuxedo is often set off with a brilliant red patch on either their head or shoulders.

A woodpecker’s bill is long and chisel-shaped; it is backed by strong neck muscles, that allow them to bash into tree bark, seeking hidden bugs beneath. To keep them from becoming addled by brain damage as they bang away, their brain is encased in a fluid shock absorber.

Their vocal calls are of three types: expressing alarm, attracting a mate, or declaring territory. Their drumming calls are primarily for similar communication—either to attract a mate or to proclaim their domain. When they excavate for bugs, they slowly, much more quietly and erratically bang away on a tree branch; but when mate-seeking drumming, their rate is far more rapid—sounding like a toy machine gun.

It’s not easy to discern which species is drumming, when I listen to them—but the big pileated woodpecker sounds big, while the little downy raps much more demurely. Although I couldn’t see the drummer on this night, I was guessing that he was a medium sized hairy woodpecker.

The usual woodpecker drumming sound is a loud rapping of 10-15 beats, way off in the woods, where the bird has found himself an echoey, hollow branch. That beat will get repeated, with the same resonant tapping, every minute or so. You can admire him as you listen, proudly announcing that he’s found himself a great percussion instrument to rap on and show off his skills.

The drumming of this guy, however, was not always repeated the same way. Although his rapping rate was quite constant, he’d bash away just once or twice, and then he’d fall silent for a bit. When he started up again, the tone of his drumming would quite different… not at all repetitive. He’d tap for a few times on what sounded like a hard spot on the limb. Then he’d switch to a dry-sounding spot, sort of like a dead wood area. Then he’d drum with a hollow, resonant sound that rang out, almost bell-like. I listened to him moving back and forth between these three locations, as if he was seeking the best sound to woo the ladies with.

I pictured in my mind a jazz drummer or an orchestral percussionist—tapping on one surface after another, making fascinating, melodic sounds, seeking just the right tonal quality. It was as if this bird was experimenting—exploring for the location that pleased him (or her) the most. I enjoyed his musical concert. I liked the variation in sounds, although I suspected that the hollow-limb sound traveled farther in the woods, and thus was more likely to reach a listening lady woodpecker. I wondered if she was enjoying the concert as much as I was, picking up on the different intonations. Maybe she was just a tone-deaf lady woodpecker, but still receptive enough to respond to his artistic drumming.

Garden Spider

Can you note the eight eyes? Click to enlarge.