Monthly Archives: December 2010

On Tame Sows and Wild Boars

When I got to the prep lab this morning, Dave had set out two birds for me to work on: a Savannah sparrow (a species with which I am becoming quite familiar) and a sleek, long-tailed Yellow-billed cuckoo. As the cuckoo thawed, however, it became clear that it had begun to spoil—this happens sometimes when a specimen doesn’t make it to a freezer soon enough after its death—and that it wouldn’t, therefore, make a good study skin. Birds whose tissues are breaking down have skin that falls apart easily, and they inevitably lose a great deal of feathers as you go along. So Dave put the cuckoo back in the freezer to become a skeleton on another day, and drew out as a replacement an exquisitely tiny Golden-winged warbler (Vermivora chrysoptera). As I’ve gotten more comfortable working on small birds, Dave has given me a good many warblers to prepare—but this Golden-winged was the first of its kind that I had ever seen. While he was taking it out of the freezer, he also told me that they aren’t a very common find around here—and so I hoped I would do a good job with the perfect little creature he placed by my tray.

Fortunately, she was kind to me, and turned out beautifully. (I can use the pronoun with confidence because later I placed a pair of magnifying goggles over my head and personally examined the minuscule, very slightly raised, very slightly shinier spot behind her kidneys that Dave, with fantastic authority, indicated as her ovary. To me it looked like a microscopic, colorless oil slick sitting on top of a larger, vaguely less lustrous oil slick. Sexing birds when it isn’t mating season is an exercise in seeing what does not want to be seen.)

But besides being beautiful (Golden-winged warblers have, as their name suggests, bright yellow plumage on their wings—but they also have golden crowns, striking patches of jet black on their faces and throats, and the most modish gray feathers you can imagine cloaking their backs), it turned out that the bird I met today was also a player in a long and fascinating history.

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Here’s how it goes. The first thing you ought to know is that the Golden-winged warbler happens to have a kind of aural twin. One of the main songs you’re apt to hear these birds sing is a two or three-note whistle that is usually described as a high, gentle buzzing, like someone breathing in and out over the surface of a nail file. But hearing that song isn’t always enough to make a positive identification, because another warbler—the much more common Blue-winged—buzzes in a very similar way. And it’s especially apt to do so if it has a little Golden-winged blood in it.

Here’s why it might. The two species of warbler don’t look all that much alike; although they share the same basic colors, the way those colors are distributed on their bodies is quite different. But DNA tests reveal that they’re incredibly similar genetically. In fact, scientists believe that two or three million years ago, Blue-winged and Golden-winged warblers were one and the same. At some point, though, glacier movements across North America caused the population to split into two groups: one isolated somewhere around Missouri, and the other somewhere up in the Appalachians. And from this separation came speciation.

For more than a million years, Golden-winged warblers and Blue-winged warblers were kept apart from each other mostly by dense forests, a habitat in which neither is able to thrive. Eventually, however, humans began clearing those forests and farming them—then abandoning that farmland and allowing a sparser collection of trees and shrubs to grow back. As this change in the landscape occurred, sometime between one and two centuries ago, Golden-winged warblers began moving north and Blue-winged warblers south. And because they still share so much genetic material, when the two meet, they are happy to breed with each other.

If a Golden-winged warbler mates with a Blue-winged, the two produce a reliably identifiable hybrid offspring known as a Brewster’s warbler. (A Brewster’s warbler is then able to mate with either a Golden-winged or a Blue-winged warbler in a process known as a backcross; these pairings, and their successive pairings, produce all manner of other subtly different and unpredictably plumaged birds, as well as—occasionally—another reliably identifiable hybrid known as a Lawrence’s warbler.)

Unfortunately, besides making for an incredibly complicated family tree, this habit of hybridization has spelled a precipitous decline in the Golden-winged warbler population. That’s because Golden-winged warblers are significantly more likely to mate outside their species than Blue-winged warblers, and—much to the chagrin of avian anti-classists, I presume—once they’ve done so, their hybrid offspring aren’t able to find mates as easily as pure-blooded birds. The combination of these two things has meant that, as the species have crossed paths over the past century or so, Blue-winged warblers are making pretty good headway at displacing Golden-winged warblers.

What truly amazes me about all this, beyond the fact that it’s biologically fascinating, is that I know perfectly well the whole story was present in Dave’s head as he handed me that sweet little specimen this morning—even though the only thing he said was “We don’t get too many of these.” Sometimes I wonder what it can possibly be like to know as much as he does about birds; how it must feel to have all this detail stored away inside him as comfortably and naturally as, for instance, you or I might store our feelings about our best friends.

You may have heard, if you live in Chicago and happen to be a newshound, that Dave’s retiring from the Field after 35 years of service. He’ll still be there every day for the next year, but when he does eventually leave it will be a loss beyond words to the division. I can’t tell you how lucky I feel to have spent the past two years working in his lab. And do you know what? If I were that Golden-winged warbler, I’d feel lucky to have passed through it too.

P.S. I owe a debt to Todd McLeish’s excellent Golden Wings & Hairy Toes: Encounters with New England’s Most Imperiled Wildlife.

P.P.S. Anyone curious about the title of this post might want to take a quick look here.

An Avian Initiation

Sometimes you have to sneak yourself in love with home, sideways, long after the fact of your leaving. It’s been more than a dozen years and I’m still figuring out what I love about the place where I grew up: how to be fond of what I once felt was pricking me in a hundred tiny ways. I’m still learning that I actually enjoy the hot, damp embrace that held me tight for so long, until I slipped free from it and catapulted into the cool, dry world. It is very easy indeed to love Singapore for my family, big and crazy and beautiful; but loving it for itself is a little more complicated. The reasons not to can loom large.

Which is why it’s a good thing I finally got the birds involved on this last visit. By 6am on December 3rd, our second full day in Singapore, having slept briefly but well under the rhythmic orbit of the ceiling fan in my sister’s guest room, and having woken early to the loud and familiar provocations of a male Asian koel (the koel is a type of cuckoo with a fantastically hard-to-ignore two-note whistle; you can hear it if you follow that link or if you ask my mother, mimic-extraordinaire, to produce it for you), Ross and I were standing outside the gate of the sleeping house, watching the stippled moon in the still-black sky. We were waiting for local birder Kim Seng to come and give us an initiation into the avian family of my funny little island—a family which, although it is perhaps not that big, definitely has its share of crazy and beautiful.

We were prepared to be pleased.

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Dragonfly as Jabba the Hut

(Ross’s happiness at being outside is more the result of bugs than birds, so it was a good thing carpenter bees, orb spiders, termites, dragonflies, and ants as long as your fingernail also accompanied us on our travels.)

The day was long, but galvanizing—one of those days that would take more stamina to write about than it did to live. We hiked through muddy, green-smelling rainforests (some parts of which were located right next to immaculately maintained golf courses being hoovered dry by attendants, but still). We wandered about wetlands thick with water birds and bathers of all kinds. We bore the burning afternoon sun as we peered into the sky at raptors soaring above flat grasslands, shot through with wide paved roads and enormous pools of leftover rain. We saw, or heard, or both, 55 different bird species, including various shrikes, doves, kingfishers, terns, sandpipers, herons, mynas, sunbirds, flowerpeckers, eagles, bulbuls, orioles, tailorbirds, flycatchers, warblers, babblers, and cuckoos. We were spoiled by flying, calling, preening life. And while I really can’t speak for Ross, I can tell you that I fell in love on at least four separate occasions that day.

Do you want to hear about my new loves? Because, listen, they are total charmers, these four, and not one of them happens to make its home on this side of the earth—so if you’re not ready to start looking up airfare from where you live to where they live, you might want to stop now. Ready?

Here we go, in order of appearance.

Greater Racket-Tailed Drongo (Dicrurus paradiseus):
We’d been hearing this bird in the gloaming for several minutes before I actually saw one; Kim Seng had pointed one out, but I hadn’t been fast enough with my binoculars to catch it in my sights before it took off from the tree where it had been perched. The greater racket-tailed drongo is a skilled mimic that practices a huge variety of calls—partly, ornithologists believe, so as to attract a large, mixed-species group of fellow insect-feeders to its side. Having done so, it can hover above them and snatch up any prey they happen to disturb but fail to catch. In exchange, the drongo keeps an eye out for predators; and if one should arrive, it cries an alarm in the language of its hunting companions.

The call we heard that morning, though, was not borrowed. It was a sweet, pure, three-note song that rose into the air like glass. To me it sounded, more than anything else, like three drops of water dripping clear and cold into a stream. In truth, based on its limpid voice alone, I was half in love with the greater racket-tailed drongo sight unseen. We kept hearing those exquisite notes as we hiked through the moist morning shadows of Singapore’s sprawling Central Catchment Nature Reserve (so called because it serves as the main catchment area for the handful of reservoirs that surround it). And after a while, as the sun began to rise upon the trees, I spotted one for myself.

Drongos are an inquisitive, aggressive family comprising about two dozen species of mostly black birds, distinguished by their long and often unusually shaped tails. Some have forked tails, some curled, and some—like the greater racket-tailed drongo—have besides all else two lovely, elaborate tail feathers shaped like flags: feathers that trail far, far down from their bottoms and twirl in the air as they fly. But I saw this one sitting, straight-backed as a teacher, on a long exposed branch by itself. I watched it through my binoculars for as long as it would let me, hoping to hear it let those three perfect drops of water fall. The drongo, though, was silent. I was not worthy of its wheedling. It simply sat, with its tail like a straightened Dali mustache, and its crest a pompadour as good as any the Fonz ever wore, and let me admire it.

Greater Racket-tailed Drongo
(Photo by Nimesh M.)

Blue-Tailed Bee Eater (Merops philippinus):
Our first encounter with blue-tailed bee eaters took place very shortly after our first encounter with the rather impressive, and comparatively rare, grey-headed fish eagle. This particular eagle was perched in a tree by the edge of the MacRitchie reservoir, apparently sleepy, full, and quite undisturbed by our attentions. It felt like a privilege to watch him so hungrily and for so long, but after we had spent a good long while observing the mild-mannered raptor through Kim Seng’s spotting scope, we found ourselves distracted by two smaller, brighter, and much livelier forest inhabitants. The bee eaters, which is what they were, kept flying off from, and then alighting on, the same branch—a not uncommon behavior among avian predators.

Their restlessness was welcome, because it meant that we had a chance to see their brilliant plumage—iridescent green, orange, yellow, chestnut, black, white, and, of course, blue—from all directions and at all angles of light as they swooped and dived like a pair of painted circus acrobats in search of breakfast. If the drongo had won me over with his voice, these two stole it with their dress and deportment. They were absolutely fascinating; even Ross was besotted with them. And do you know what? I think they knew it. We kept seeing and recognizing blue-tailed bee eaters as we went along for the rest of the day, even as we moved to different areas and different habitats. Perhaps, in fact, they wanted to be recognized. After all, if you were a bird so gorgeous as this, wouldn’t you care to show off?

Bird - Blue Tail Bee Eater
(Photo by najeebkhan2009.)

Dollarbird (Eurystomus orientalis):
This was another bird we’d heard earlier in the morning (sending out a low, unmusical cackle not unlike an upset squirrel), but I hadn’t been able to see. Dollarbirds are colorful, almost clownish-looking birds, a little bigger than a blackbird in size; they have bluish-green plumage, bright orange beaks, and clear, round spots of white on the lower half of each wing, as big as dollar coins and as bright. They belong to a family of birds known as rollers, all of which are known for the gymnastic tumbles and spins they sometimes perform in flight, especially during courtship. Unfortunately, the dollarbird we saw—which graced us with its presence as we crossed a boardwalk over the water in the middle of a lush mangrove swamp—was either already mated or content, for the moment, to remain a bachelor—for it stayed in its position on a solitary tree branch overlooking the water for as long as we cared to watch.

So why did I love the dollarbird despite its refusal to engage in the acrobatics for which its family is famous? Because it was doing something equally endearing instead: it was sunbathing. As I watched through the scope, it stretched out both wings till I could see those bright white spots, letting them hang long and relaxed below the branch on which it sat. At the same time, it rested its head on the branch, turned it to one side, and closed its eyes. It could not have been exposing more of its feathers to the warm Singapore sun unless it had been supine on the ground. And in this pose, the dollarbird looked extraordinarily relaxed. I find it difficult, actually, to describe just how relaxed. Let me just say that this bird looked like it was in it for the long haul. It seemed, friends, as if it were a bird that had learned one really awesome yoga position, and meant to milk it for all it was worth.

Since I often find it hard, myself, to really let go and unwind, what I fell in love with was this dollarbird’s sheer dedication to hanging loose.

佛法僧  Broad-billed Roller-雄亞成
(Photo by Kevin Lin, titled “Broad-billed roller” but showing what looks to me like a dollarbird, and in a pose very reminiscent of my own yoga-practicing friend.)

A moment after we saw the dollarbird, I met the bird I fell hardest for that day.

Brahminy Kite (Haliastur indus):
The Brahminy Kite is a bird shrouded in history and lore, although I didn’t know any of that when I spotted it in the sky and began staring at it like a schoolgirl in love. It was keeping company with a fierce little Japanese sparrowhawk at the time—waiting, perhaps, for it to make its kill. All I knew then was that I was looking at a singularly handsome bird, and the more so with the sun shining through its wings as it banked and glided above me, making it look like it was haloed in gold.

Brahminys have white head, neck, and breast feathers; the tips of their tails and the lower shafts of most of their wing feathers are also white, while their primaries are dipped in black. But the rest of their plumage (and this is the thing that made this one look so golden when I saw the sun casting itself over its wings) is a rich, glossy chestnut color, a reddish brown that is like the warmest possible wood: like a cedar chest someone has oiled with care every day of its life. They are gorgeous creatures.

Early scientists, it appears, were troubled by the Brahminy’s regal appearance, since its habits were so vile and ignoble (it, like most kites, is primarily a scavenger). But mythology has always given this beautiful bird its due. In India the Brahminy is revered, regarded as it is as the modern earthly manifestation of the Garuda: the massive bird-like mount upon which Vishnu rides. And among certain Indonesian peoples, the keenness of the bird’s talons is believed to derive from a magical stone it hides in its nest and on which it sharpens its claws. You can steal it to sharpen your own knives, the stories go—but only if your eyes are tightly shut as you reach inside the Brahminy’s nest. If you dare to so much as peek while your blind, robbing hand stretches out, the stone will disappear, or transform itself into a nestling.

Me, I would never be so bold. Not with such a king of birds.

Brahminy Kite - Haliastur indus
(Photo by Mike (NO captive birds) in Thailand.)

I have to admit that it’s a little scary to look so deeply at a place so familiar. It’s a little disorienting to find yourself falling in love with home, and realizing just how tiny a fraction of it you ever understood. But when it’s birds that carry you along, it doesn’t feel like falling at all.

It feels like flying.

On Sultry Dreams

You cannot counterfeit the air.

I have lived where the air is thick, crowded, and heavy—where the space rightfully allotted to the air, immense though it seems this must be (comprising, as it does, all of the vast latitudes and infinitesimal interstices left behind once earth, tree, stone, sea, and every animate and inanimate thing has taken up its place in the world), has nevertheless run out.

Where what space there is has become saturated with the dampness of sweat and steam and the rising puffs of the air’s own slow-moving breath. I have lived where molecules of water in the air are so numerous and insistent that they jostle hard against molecules of nitrogen, oxygen, hydrogen, carbon dioxide, and tell them where they can stick it; where moisture besieges the pathways of the atmosphere like a rabble of old ladies, each one with her elbows out and umbrella a-kicking, each one rioting wetly against the delicate knees of those rarer and more noble gases that flit nervously out of the way.

Humid, they call the air in such a place, but what I call it is mobbed. And you cannot counterfeit this with your humidifiers and your steam rooms and your dreams of being there. You cannot counterfeit the air.

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