Crow wars

holloway overhung with ancient trees n Cornwall

I think I just witnessed a gang war between crows. It was a little before ten in the morning, on a day with intermittent flurries. At first I thought the crows were mobbing a predator – that’s what it sounded like – but then I realized they were diving at each other in the sky over Sapsucker Ridge to the west. More birds kept streaming overhead from the east all the while I stood watching, about ten minutes. Most of them landed in the treetops and added their voices to the raucous cheering section for the aerial battles, which included at least a couple dozen combats at a time; the ridge blocked my view of a lot of the action. Brisk winds aloft made for an exciting display of maneuvers: diving, chasing, feinting – Top Gun stuff, for sure.

As is usual with crows, it’s difficult to know how to interpret what I was watching. Maybe it was all just play behavior, occasioned by the wind conditions. Ten minutes later, when I stick my head out the door, there’s no sign of a crow anywhere.

Most non-specialists would probably tend to assume that scientists know a lot about the behavior and life histories of the commoner birds and mammals, especially here in the northeastern U.S., but such is rarely the case. A recent study of white-tailed deer, for example, made a couple surprising discoveries simply by fastening digital cameras to bucks’ antlers: deer touch muzzles constantly, they found. And one deer kept returning to the same spot to drink, despite the availability of closer water sources. What’s surprising about this is that white-tailed deer are probably one of the most-studied animals in the world, apart from human beings, laboratory rats, and fruit flies. How could previous researchers have failed to notice such apparently common behaviors?

So I wasn’t sanguine about throwing much light on what I’d just seen by a quick glance through the literature on the American crow (Corvus brachyrhynchos). The Stokes Guide to Bird Behavior, Volume 1, confirms that “There has been amazingly little study of Crows by researchers, so most of the best questions about the birds still cannot be answered.” Its summary of research to date (1979) included this:

Outside of the few months of the breeding season, Crows are extremely gregarious. After the last young have fledged, the family group usually joins other groups of Crows, and these begin to form a large flock that divides up for feeding during the day, but gathers again each night to roost. The roost becomes an important focal point in the birds’ life outside the breeding season. Each morning the roost breaks up into smaller flocks that disperse across the countryside to feed. Some flocks may fly up to fifty miles from the roost each day. In midafternoon these smaller flocks start back toward the communal roost. They fly along flight lines used each day and are joined by other flocks as they go. Often there are preroosting sites, where flight lines coincide and Crows stop to feed before making the final trip to the roost. At these spots there may be much chasing and other spectacular dives as the returning Crows join the others at the preroosting spot. Then just before dusk all the Crows in the area enter the roost site together.

What I saw would seem to have occurred at the wrong time of day for preroosting behavior. But this description does make it clear that not all chasing and diving is antagonistic.

In The American Crow and the Common Raven, Lawrence Kilham describes territorial antagonism across a boundary between two large groups of crows in Lyme, New Hampshire.

I watched forty-five territorial encounters beween 1981 and 1983. While no two were alike, certain behaviors were observed repeatedly. Cawing, heard in thirty-eight of the territorial encounters consisted of sharp caws corresponding to what Good (1957) refers to as warning calls and Camberlain and Cornwell (1971) as simple scolding calls. The crows of both groups cawed when flying toward each other at a distance. This was especially so on early mornings when most encounters took place. If one group alighted in the fields and another in trees, the latter did the most cawing….Other forms of behavior [aside from walking and bluffing displays] included aerial melees (n = 17), bunching (n = 5), and pursuits (n = 5). The melees were spectacular when all members of both groups swirled into the air for three or four seconds, with some swooping on others….

Territorial behaviors also included circular flights (n = 11), which carried the crows of one group a short distance over the boundary into their neighbors’ territory as if to demonstrate where the boundary lay, and treetop sitting (n = 17). The latter was particularly striking on November 26 [1983] when the crows of both groups, after a series of melees, perched on the very tops of their dead elms in full view of each other.

Kilham found that groups facing off over common boundaries tended to be “of the same or about the same size.” None of the conflicts he observed seem to have resulted in serious injury, let alone death. And he speculates that most of the actual combats are left to the dominant or nuclear males, based on his observations of American crows in Florida, and on another scientist’s observations of white-winged choughs, which have similar social patterns.

A more recent source of information is the American Crow monograph for the authoritative Birds of North America series: No. 647, by N. A. M. Verbeek and C. Caffrey, 2002. Over twenty years after Stokes, not much has changed: “Although much has been published about this [species of] crow, we still know relatively little about it.” They add that observations made in one locale may not describe the behavior of crows from somewhere else in the species’ range.

One of the things that appears to vary from place to place is whether territories are maintained throughout the year. Crows on Cape Cod and in New Jersey, California, Oklahoma, Florida and New York do maintain year-round territories, but crows in Ohio and in the northern part of their range in Canada do not. So goodness knows where central Pennsylvania fits. On the topic of aerial melees, Verbeek and Caffrey simply quote Kilham. If there haven’t been many other observations in the literature, that may be because few observers are as patient as he was (me, I went inside when my hands began to freeze). Also, given that American crows favor mixed and open habitat, territorial boundaries might tend to pass through forested areas or follow wooded ridgetops, making interactions along them harder to observe.

As habitat generalists and omnivores with well-developed learning abilities and complex social structures, crows offer many parallels to the behavior of humans and other primates. To a non-scientist like me, it seems natural to characterize group antagonistic behavior as a gang war, but I have to be careful not to let my judgements be too colored by prejudices which are not merely anthropocentric, but ethnocentric as well. For example, we Westerners tend to associate wars with struggles for dominance, leading ideally to the conquest of one group by another. But among the crows that Kilham observed, territorial conflicts seemed to work more to maintain a balance of power – not unlike the low-intensity conflicts that are thought to have been the norm for warfare in much of native North America before 1492. Kilham watched wandering flocks numbering as many as forty crows trespass into group territories without much conflict beyond a lot of cawing. These flocks apparently consisted of nonbreeders – juveniles with no interest in setting up a territory of their own.

It’s also important to remember that territories are maintained cooperatively, for the shared benefit of the crows that use it: “Territories provide improved protection through greater familiarity with safe areas; reduced interference with nest building and copulations; greater protection of stored food; and increased assurance of a good food supply,” Kilham notes. Nor does cooperative behavior end when the breeding season is over. Fall and winter roost sites can only get to be as large as they are by bringing together crows from diverse, non-overlapping daytime feeding territories, and mixing local birds with migrants – foreigners from the north. I wonder if the diving and chasing behavior commonly observed at preroosting sites doesn’t represent a playful, ritualistic form of inter-group conflict? After all, even among humans, the line between play and warfare can get awfully fuzzy – think of the World Cup. In any case, whether we choose to focus on the relatively rare, spectacular outbreaks of crow-to-crow combat, or on the cooperative nature of crow sociability as a whole, probably says a lot more about us than it does about the crows.
__________

The most promising research on American crows since Kilham comes from Kevin McGowan of Cornell University, who has been banding crows and following their progress from year to year since 1988. His crow website includes helpful information on roosting behavior in the F.A.Q. page, and an overview of his own crow study, with links to publications. He writes, “I frequently see crows locked together tumbling out of trees in the spring. Although I have never witnessed an actual killing, I would not be at all surprised to see crows kill another crow from outside the family group that was trespassing.”

Doubting against doubt: finding the grail bird

holloway overhung with ancient trees n Cornwall

Here’s a book review to wrap up Summer Book Week. Thanks are due to my father for posting (and copyediting) in my absence, and to him, my mom and my brother for sharing their expertise in “favorite books” posts.

Image Hosted by ImageShack.usI try hard to avoid anything topical at Via Negativa, but as regular readers will remember, I made an exception for the rediscovery of the ivory-billed woodpecker, announced late last April. In company with a lot of other folks, I saw it as a real emblem of hope – maybe ecocide can still be averted. Maybe there’s still time.

Since then, one of the most pivotal re-discoverers, Tim Gallagher, has had his book published by Houghton Mifflin, The Grail Bird: Hot on the Trail of the Ivory-billed Woodpecker. This was no instant book, but had been in the works for some time; an epilogue gives an update as of February 2005. And Gallagher, the editor of Living Bird magazine, is no slouch as a writer.

Mostly, The Grail Bird is just a good yarn, filled with engaging portraits of the various characters who have stalked the bird for science, from the 18th century to the present. I hadn’t realized the extent to which scientists had helped decimate the last surviving populations in the late 19th and early 20th centuries through their insatiable urge to collect. The attitude of ornithologists toward birds was strikingly similar to the attitude of early anthropologists toward the “primitive” people they studied: gather all the hard evidence possible, including corpses, because of course their continued existence is incompatible with human progress. The role of the scientist was to document the march of rare species and indigenous peoples toward extinction. But while the mainstream of anthropology has long since repudiated this truly primitive mindset, evidence suggests that ornithologists are having a great deal of trouble accommodating any other storyline.

The real hero of the book is Gallagher’s good friend and fellow ivorybill fanatic Bobby Harrison, a roly-poly Southerner with an insatiable hunger for Snickers bars and Dinty Moore beef stew and an uncanny penchant for taking the long way around, whether on foot in snake-infested swamps or traveling cross-county in his beater of a van. It’s Harrison, along with Arkansas natives David Luneau and Gene Sparling, who maintains a constant vigil in the swamp. Wave after wave of crack birders from Cornell and elsewhere spend varying lengths of time in the area trying to collect solid documentary evidence of the Ivorybill’s existence, but in the end it’s the fanatical Harrison and Luneau who come up with the brief, blurry videos that remain the most solid evidence to date (if one discounts the excellent audio recordings of ivorybill calls from several locations).

The Grail Bird ought to appeal to a much wider audience than just birders. The story of the ivorybill’s repeated rediscovery and subsequent dismissal by legions of skeptics throughout the latter half of the 20th Century left me pondering the nature of doubt. Ever since the so-called Enlightenment of the 18th Century, we have been accustomed to regarding unquestioning faith as problematic; I can’t remember ever hearing a critique of “blind doubt.” But following the crushing loss of the Singer Tract in the 1940s, the American ornithological community has fallen prey to a fey kind of fatalism in regards to the ivorybill. No proof is good enough, and any ornithologist so foolhardy as to claim to have seen it – or even to believe in the veracity of a sighting – risks irreparable damage to his reputation.

That was the case with John Dennis, who had taken what was generally acknowledged as the last irrefutable photo of an ivorybill in Cuba in 1948. His claim to a sighting in the Big Thicket of East Texas in 1966 was roundly ridiculed. With Harrison’s help, Gallagher is able to relocate a sound recording Dennis had made, and the analysis of the sonogram convinced audio technicians that the call on the tape could only have been made by an ivorybill.

In another coup of investigative journalism, Gallgher tracked down the previously unknown individual who took the controversial snapshots of an ivory-billed woodpecker in Louisiana in 1971. The then-head of the Louisiana State Museum of Natural Science, George Lowery, had presented the snapshots at the annual meeting of the American Ornithological Union that year and was astonished at his colleagues’ reactions.

Lowery’s pictures were met with immediate withering skepticism by most of the other ornithologists. The photos showed two different trees, but the posture of the bird in them was too similar. You couldn’t see its bill or feet. Somehow, it just didn’t look right. And yet the question remained: why would someone go to all the trouble of climbing fifty or sixty feet up two different trees to fake these pictures – particularly since the man who took them wished to remain anonymous?

In this case, the skeptical reaction appears especially unscientific. Not only did the skeptics’ explanation fail to satisfy Occam’s razor, but their refusal to even entertain the possibility that a population of ivorybills persisted in an area with extensive tracts of suitable habitat, as attested to by a well-respected biologist, was the very opposite of the open-minded search for truth that is the supposed hallmark of Western science.

Gallagher and Harrison are among the dedicated few who never allowed themselves to believe that the ivorybill had gone extinct. It’s not that they were ever fully convinced that the bird still existed, simply that they refused to dismiss what struck them as convincing accounts by credible witnesses. They dared to “doubt against doubt,” as it were. Significantly, neither is a professional ornithologist. Each is an amateur in the best sense of the word: etymologically, a lover, someone passionately dedicated to a pursuit. Of course, plenty of scientists are also passionate advocates for the natural world: one thinks of E. O. Wilson, Reed Noss, Michael Soulé. Without true passion to burn off the choking thickets of fatalism, I wonder, can the mind ever find room for dispassionate analysis?

It’s not that Gallagher doesn’t understand where the skeptics are coming from. He gives a very sympathetic portrait of one of his colleagues at the Lab, Kevin McGowan, whom he describes as “the resident skeptic.” For McGowan, it seems, a bird in the hand is worth a hundred in the bush.

He wants to see empirical evidence for everything. This may be because he was the curator of Cornell’s bird collection for a long time and is used to dealing with evidence that you can see or touch, such as bird specimens. He is careful and precise, and if he says he saw something, there is little doubt that he did. …[H]e has less than perfect vision. He is obsessed with visual clarity to such an extent that he insists on only real glass lenses in his eyeglasses, not plastic, despite the extra weight.

After seeing Luneau’s video, McGowan is finally convinced.

“I wanted to believe before,” he told me. “But it’s in my nature to be skeptical. I just couldn’t help but have doubts, even though I trusted the abilities of some of the people who’d had sightings. It wasn’t until I saw David Luneau’s video that I really accepted the existence of this bird.”

Seeing, as they say, is believing; everything else is hearsay, even the best audio recordings. This attitude is especially curious in a field where identification by human or electronic ear is more and more heavily relied upon to verify the presence of breeding or migrating birds. Cornell Lab has taken a leading role in promoting this kind of research, as well as enlisting legions of amateur birders as so-called citizen scientists for all kinds of studies, so it is only appropriate that the Lab should’ve led the ivorybill rediscovery effort. But even the Lab’s best people are not immune to the debilitating influence of irrational disbelief. Gallagher recalls interviewing one of the searchers, woodpecker expert Dr. Mindy LeBranche, on the evening of the day when she had a good, clear sighting.

I was annoyed that so many people were throwing out percentages about how sure they were that they had seen an ivory-bill. Ron and David were maybe 85 percent sure; Jim Fitzpatrick was 98.5 percent sure; now here was Mindy saying she was 99 percent sure of her sighting.

“What’s all this crap I keep hearing about people being 90 percent sure, 95 percent sure that they saw an ivory-bill?” I said. “What is it about your sighting that gives you that one percent of doubt?”

Mindy shot right back: “Because the bird is freaking extinct! For years I’ve been convinced of that. And that’s why I can’t be a hundred percent sure.”

As we spoke, I left the camcorder running, and it was still taping for a while after the interview was over. When I played it back later, it was interesting to watch the expressions on her face while conversations went on all around her. People were laughing and joking nearby, and she would occasionally laugh along with them, throwing out a comment or two. But every time she stopped talking, she would withdraw into herself. Her face at times looked almost horror-struck, almost like that of a person in shock – or perhaps like someone who has…well, seen a ghost.

Just in the past week, the news media have gleefully seized upon reports that a number of prominent birders and ornithologists are increasingly willing to air their doubts about the rediscovery. An article challenging the evidence is scheduled to appear in an as-yet unnamed journal, with rebuttals and counter-rebuttals. The New York Times quotes two prominent birders, David Allen Sibley and Kenn Kaufman, questioning the reliability of the evidence collected to date. Both have recently authored best-selling bird guides, and both took the unprecedented step of excluding the ivory-billed woodpecker. So for the damned bird to reappear just after they had literally written it off is a bit of an embarrassment, to say the least. (Sibley subsequently uploaded a PDF file of an insertable ivorybill page at his website.) As for the scientists,

“The people who originally announced this thoroughly believe they got an ivory-billed woodpecker,” said Mark B. Robbins of the University of Kansas, one of the three scientists preparing the challenge to the Science report. “They believe one thing, we believe another. This is how science plays out, the fabric of science getting at the truth.”

Except that in this case, the fabric of science appears to be a funeral shroud. As my brother Steve recently remarked, when did it become unscientific to assume that a species is still present until the last acre of suitable habitat is completely eliminated? There’s a kind of arrogance at work here that says that since we can’t find something, it must not be there. But do we really know where and how to look? Considering that the Cuban subspecies depends on pine forests rather than bottomland swamps, it’s clear that our knowledge of the ivorybill’s habitat preferences and adaptability is miniscule.

Sibley reviewed The Grail Bird for the Boston Globe last month. Though he says he liked the book otherwise, he takes strong exception to Gallagher’s critique of the scientific community. “[T]rue science, objective and unbiased, has to be based on concrete, testable evidence. Since 1944 there has been no conclusive evidence to go along with the sightings,” Sibley intones. At this point, though, I wonder if the doubters would be satisfied with anything less than a corpse.
__________

See also Learning from the ivorybill, The finding and The thing with feathers.

Raincrow

holloway overhung with ancient trees n Cornwall

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Yesterday around noon and again this morning early, a black-billed cuckoo has been calling from the woods’ edge. He sounds like the spirit-world counterpart of his commoner cousin the yellow-billed.

Cuckoos of either species are mysterious birds, so oftener heard than seen, skulking in the thickest parts of the forest canopy where they wait motionless for long periods before rocketing into action, ambushing their caterpillar prey. “Cuckoos eat many spiny caterpillars and the spines stick in the lining of the stomach,” the webpage for the black-billed cuckoo informs us. “The stomach lining is periodically shed to remove the spines.”

The first time I got a good look at one, I realized suddenly where those long, narrow-bodied birds in Pennsylvania German folk art came from. Messenger of love, said Europeans about the cuckoo’s old-world namesake, which lays its eggs in the nests of other birds so it can spend all its time in courtship. Raincrow, the Indians called both the yellow- and black-billed cuckoos for their tendency to call more frequently before storms. They also typically return at the same time as the early-summer rains.

The cuckoo is one of the last neotropical migrants to arrive in North America and has very little time to build a nest, find a mate, lay its eggs and raise its young. To do so, it has evolved a unique nesting strategy. It is able to time its egg laying with outbreaks of insects (especially caterpillars) so that it has a rich food source for itself and its young. Its incubation/nestling period is the shortest of any known bird. Its egg develops rapidly, and at hatching is one the heaviest of all North American songbirds. This is because the chick will have very little rearing time before embarking on its transcontinental migration – it must complete much of its development while still in the egg and come out ready to go. The nestlings are fledged from the nest 6-7 days after hatching, and are off to South America at three or four weeks of age.

Thus the Center for Biological Diversity, based in the western U.S. where the yellow-billed cuckoo is nearly extinct as a result of habitat destruction.

This morning at first light a thrush flies past the porch on loud wings, like a fast smack of oars against the surface of a pond. A bat loops and dives, half-visible against the darker trees. It has been astonishingly humid, with daily and sometimes hourly thunderstorms. The raincrows call almost without a pause. Walking in the woods has become, for me, a misery of sweat and deerflies. If the air were any thicker, we would need periscopes to find our way.

*

GROWTH

Mind poised at
the tipping point
in a fantasy of perpetual motion
like an old-fashioned toy,
wooden bird hinged
at the hips that bends
again & again into
the undiminished fuel
of its reflection.
Last week, I saw
the sun in the surface
of a bog: it bubbled.
It trilled like a toad.
The alchemists
would be pleased, mercury
now lurks nearly everywhere.
Its needle threads the eye
of mother’s milk, quick-
silver fin & feather, legs
of a heron. Extract
of death, let us dance.
Let our bones be honey-
combed with light.
Bulbous, wedded
to our rituals,
we take turns bending
at the hips.

A route of evanescence

holloway overhung with ancient trees n Cornwall

A Route of Evanescence
With a revolving Wheel –
A Resonance of Emerald
A Rush of Cochineal –
And every Blossom on the Bush
Adjusts its tumbled Head –
The mail from Tunis – probably,
An easy Morning’s Ride –

EMILY DICKINSON

First light. From my chair on the front porch I can hear a ruby-throated hummingbird (Archilochus colubris, the only hummingbird species we have here) just around the corner of the house. I get up and look: it’s a male, filling up on nectar from the comfrey flowers. Out of all the more showy flowers in my garden, it’s the nondescript, reddish-purple comfrey that’s drawing the hummers right now. Watching the crimson-throated male thrust the tiny sword of his bill into the flowers’ upside-down cups, I think of one of the Spanish words for hummingbird, picaflor.*

Contrary to popular belief, a hummingbird’s bill is nothing like a drinking straw. It opens just wide enough to allow the bird to lap up nectar with its brushy-tipped tongue, which zips in and out at the rate of thirteen times per second. The hummingbird tastes little of the flowers, other than their relative concentration of sugar, and he smells nothing at all. His vision, however, is acute. And anecdotal evidence suggests that hummingbirds have long memories, as well, in some cases appearing to form strong bonds with human benefactors and returning to visit them throughout the season and even in subsequent years.

A long memory would be a highly adaptive trait for a creature whose survival depends on being able to find reliable sources of nourishment from food sources that change by the day and even by the hour. One wonders how many details of his thousand-mile round-trip migrations he can recall from one year to the next. Imagine what the mental map of a hummingbird might look like: bright jewels of color like beads in a rosary stretching from Pennsylvania down through the Appalachians to Georgia, west along the Gulf Coast and then south through Mexico to Guatemala, Honduras, Nicaragua, even Costa Rica.

The male rubythroat returns twice more to the comfrey during the half-hour I’m out on the porch. I recall what an ornithologist recently told a meeting of our Audubon chapter concerning hummingbirds: the males are smaller than the females, just barely above the energetic limit for warm-blooded creatures, below which it isn’t possible to eat quickly enough to stave off hypothermia. And they expend so much energy on their spectacular, U-shaped mating/territorial flights and in fighting with other males – chasing, jabbing with their bills, striking with their feet – that they have few fat stores left over to keep them alive during the cool spring nights. Many of them don’t make it. It’s not unusual for female hummingbirds to outnumber males four to one by the end of their first breeding season.

Hummingbirds are unique to the New World, and occupied a prominent position among the marvels described by the first European explorers. It occurs to me that the Aztecs were well justified in associating the hummingbird with their kamikaze-like warrior cult of death and flowers – especially that crimson flower in the chest, whose sacrifice they thought necessary to feed the sun. A ruby-throated hummingbird’s heart can beat 1,220 times a minute. It accounts for some 2.5 percent of the bird’s total body mass, which means that in proportion to its size, the hummingbird has the biggest heart of any member of the animal kingdom.

Ironically, for a creature still associated with male prowess in some parts of Latin America, the male hummingbird has no penis whatsoever. He fertilizes the female merely by touching the tip of his cloaca to hers for a fraction of a second; his relationship with flowers is vastly more prolonged and solicitous. During the non-breeding season, the sex organs of both the males and the females shrink to a tiny fraction of their active size to make the birds better fit for their lengthy migrations, like backpackers chucking every ounce of unneeded gear. For the same reason, the female makes do with a single ovary.

They leave for Central America when the nighttime temperatures here are barely above freezing, flying low to the ground to avoid cooler temperatures aloft. Just before and during migration, their diet becomes largely insectivorous as they stock up on fats and proteins, often doubling their body mass. In the tropics, rubythroats may continue to rely much more on insects than on nectar. But even here, a sizeable proportion of their ordinary diet consists of small insects found in, on or in the vicinity of flowers, as well as pollen, which they play a major role in spreading from plant to plant. Their ability to key in on bright spots in the landscape probably allows them to quickly locate their favorite kinds of insects during migration. Their breeding range maps closely to the range of eastern deciduous and mixed deciduous-coniferous forests – a fact which may also have direct dietary relevance, since they sometimes rely on tree sap when no suitable flowers are in bloom. Their arrival back north (late April to early May in Central Pennsylvania) seems to be timed to take advantage of sap flows in birch trees “tapped” by the yellow-bellied sapsucker, though doubtless the presence of small insects also plays a role.

It always boggles me a bit to think about pollination: one species relying on another, completely unrelated species to perform what is, for us, the most intimate of acts. The variously curved and elongated bills of hummingbirds are well adapted to flowers with deep throats; their co-evolution suggests an effort on the part of the flower to exclude insect pollinators, whose senses and memory may not be up to the task of properly cross-pollinating between widely scattered individuals or populations. At least nineteen species of plants in North America have co-evolved with hummingbirds as a primary pollinator, including trumpet creeper, beebalm and jewelweed. With their bright, iridescent colors, hummingbirds seem more than a little like flowers themselves – or rather, like a flower’s wet dream.

But it’s no surprise that birds with such highly developed visual cortexes would wear bright colors; the primary audience for a male hummingbird’s aerial display is, of course, another hummingbird. From where I sit here at my writing table, looking out my front door, I am often treated to a partial view of this display, probably from the very same bird I saw at the comfrey this morning. He hurtles back and forth along a hyperbolic arc like the pendulum for some invisible, mad clock, his metallic green plumage flashing in the sun.
__________

*The usual, more literary word – as in the first of the two Lorca poems I translated yesterday – is colibrí­. But in my brother Mark’s Birding Honduras: A Checklist and Guide, there are neither picaflores nor colibrí­s, but gorriones and gorrioncitos – words otherwise applied to sparrows. In other Spanish-speaking countries, the term chupaflor – sucks-the-flower – may be used instead of picaflor (pecks-the-flower). And in Brazil, a hummingbird is beija-flor, kisses-the-flower – arguably the most appropriate name of all.

Primary sources for this essay included: T. R. Robinson, R. R. Sargent and M. B. Sargent, Ruby-throated Hummingbird, No. 204 in the monograph series The Birds of North America, edited by A. Poole and F. Gill, The Academy of Natural Sciences and American Ornithological Union, 1995; Alexander F. Skutch, The Life of the Hummingbird, Crown Publishers, 1973; and the terrific (if poorly designed) website for Operation RubyThroat: The Hummingbird Project.

Learning from the ivorybill

holloway overhung with ancient trees n Cornwall


Drawing by Mark Bowers, from the U.S. Fish and Wildlife Service website
(link via The Daily Blatt)

1. Mr. Wile E.

A week ago, when I heard the news about the rediscovery of the ivory-billed woodpecker, I was – as I mentioned – afflicted with a sudden and unaccustomed surge of joy and hopefulness about the state of the planet. After a couple hours of reading on-line articles and corresponding with my two birder-brothers about it (my parents being on vacation and out of e-mail reach), it occurred to me to send a message to the listserve of the Pennsylvania Biodiversity Partnership in my capacity as co-chair of the Public Lands Committee of the Pennsylvania Chapter of Sierra Club. After a link to the Cornell Lab and a few other remarks, I concluded, “The message for Pennsylvania is clear: Recover It (old-growth forest) And They Will Return.”

Yes, that’s right. Even in the midst of my jubilation, I couldn’t resist putting my own spin on things. And in fact, it bore satisfactory results: it sparked a good discussion of old-growth on the listserve, and my reaction against my own opportunism led to a half-decent poem two days later.

But Coyote wasn’t fooled. I neglected to mention this at the time, in part because I figured y’all might suspect me of making it up. But it’s true. It was about nine o’clock that evening, and I had been listening to some of my favorite country blues cassettes (remember cassette tapes?) while drinking three or four celebratory bottles of homebrew. (It was, unfortunately, too cold to sit outside.) Then I got hungry, and remembered some leftovers up at the other house, in my parents’ refrigerator. The night was dark. Just as I got to the top of the hill, a coyote let loose from the middle of the field – less than a hundred yards away. The hair stood straight up on the back of my neck. He or she howled a couple of times, then barked like a dog: Har! Har! Har! Har! Har! I scuttled inside, grabbed the highest-powered flashlight I could find, and shone it back and forth across the field, hoping to pick up the eye shine, but the animal had already slipped away.

Now, to appreciate this incident, especially if you’re from out west, you have to understand a couple of things. First, that eastern coyotes don’t vocalize nearly as often as their western counterparts. Second: the eastern coyote is, depending on which biologists you believe, either a brand-new animal here in the east, or a once-eradicated species that reintroduced itself in the latter half of the 20th century. The latter theory postulates that European settlers, being unfamiliar with the North American coyote, simply mis-identified it as the “brush wolf” – which they then proceeded to wipe out as quickly as they could. The problem with that theory is that coyotes are virtually impossible to eradicate. Since they have always played second fiddle to wolves, it makes sense that they would evolve an extremely flexible population ecology: the more you persecute them, the faster they reproduce. Gray wolves, having evolved (at least since the demise of the dire wolf) as top dogs, have no such resilience.

But canids speciate as much by culture as by genetics, which is to say that species boundaries are readily crossed, and only mutual hostility and fear of being eaten prevent interbreeding – 99 percent of the time. A DNA analysis of eastern coyotes did strongly suggest that interbreeding with timber wolves – the smaller subspecies of wolves inhabiting eastern Canada – had occurred in the recent past. But who knows? Perhaps there were a number of regional subspecies in 1600. Some biologists argue that the Pennsylvania “brush wolf” was neither gray nor timber wolf, but the red wolf of the southern Appalachians.

Does Coyote care about all this? I think not. This new/old wild canid has figured out that frequent howling in the densely populated east is not advantageous. Nearly every hunter in this state owns a powerful spotlight, and coyotes may be shot anytime as a varmit. The easiest way to do this, I’m told, is by playing tapes of their howls. Meanwhile – and very anecdotally – I hear from folks in Vermont and West Virginia that an even larger coyote is beginning to appear. It’s probably only a matter of time before wild canids in the northeast switch from opportunistic predation to direct reliance on our hugely over-abundant white-tailed deer herd. I hope.

Of more direct relevance to the ivorybill rediscovery is the fact that the presence of coyotes in the state was officially denied for years – decades, in fact. Even as sightings grew more frequent and the evidence more and more overwhelming, spokespeople for our state wildlife agency continued to deny the obvious. The name of this agency might tell you why: it’s the Pennsylvania Game Commission. It derives almost all its funding from the sale of hunting licenses, and all license increases must be approved by the state legislature. Game Commission folks knew that the interval between official acknowledgement of the coyote’s presence and demands for its eradication would be about two or three nanoseconds, so they stalled as long as they could. When it finally became impossible to deny the obvious – some fifteen years ago now – they announced it as a wonderful new addition to the state’s already impressive roster of legally trapable and shootable critters. They made it sound like such a good thing, in fact, that to this day they are regularly accused by more credulous members of the hunting fraternity of having deliberately introduced the animal, as part of vast and sinister conspiracy between anti-hunters, the Audubon Society, and the United Nations. These are, of course, the same anti-hunters who want to slaughter all the deer in the state. As Dave Berry would say, I swear I’m not making this up.

In fact, I know this guy who knows a guy who drives truck, and one time about fifteen years ago, after a couple beers, he says to my buddy, “You won’t believe what I got in the back of my truck…”

2. How much old-growth is enough?

One of the first two responses to my e-mail to the Biodiversity Partnership listserve raised some interesting questions:

I have been told the ivory-billed woodpecker has been seen by outdoorsmen in the Arkansas area for years. No one of any “authority” believed the people who saw them. Now that some upper-shelf person saw one, it is now for real. Great, but the same can be said for other animals in the eastern US: cougars, badgers, wolves, lynx, Allegheny wood rat etc. come to mind. It is time we get our heads out of the sand and put a little effort into documenting other animals in our midst.

The author, Gene Odato – chief of the Rural and Community Forestry section of the Pennnsylvania Bureau of Forestry – responded to my spin with some of his own. If some of these supposedly endangered or regionally extinct species are, in fact, present, then what do we have to worry about? If anything, we have too much old-growth – and not enough young forests.

I would like to know more about the nature of that forest in the Cache and White River bottoms: year last cut, degree/type of management, etc. That would be very instructive to us all.

I would also like to know more of the management details of the land the woodpecker inhabits. As for PA or any other state: How much old-growth is enough without damaging the lives of the people who depend on the wise use of the forest? The public land such as the national forest and in particular the state forest of PA already manage 30% to 50% of the forest as old-growth. How much more do we need without sacrificing the habitat needs of hundreds of wildlife and plant species that depend on early successional forest, poletimber-sized forest?

I asked my brother Mark to do some digging – something which, as a geographer, birder and conservationist, he didn’t have to be asked about twice. In fact, even before he headed over to Arkansas last Saturday, he fired off a preliminary e-mail in response to some of Gene’s concerns.

All I can say at this point is that Arkansas appears to be quite a bit more advanced than Pennsylvania – after all, its motto is “The Natural State” rather than the “Keystone State.” Arkansas parks are some of the most impressive I’ve seen. It takes some guts or gall to block a bridge across the Mississippi River from this county (Bolivar), the epicenter of cotton production in the US, across to Ark, but they did it years ago to avoid destroying the White River Refuge. Thanks to the White River National Wildlife Refuge, there is no unbroken road along the Mississippi River on the west side of the river through Arkansas. (Where this bird was rediscovered, however, is right off the Interstate, well north.)

I’m just not quite convinced that people up in the northeast can conceive of the size of some of the wildernesses down here, nor understand that the old-growth was logged as recently as the 1940s, and never really completely, at least in Arkansas and Louisiana (Mississippi is a different, sadder story, of course) – the Big Forest, like this side of the river, was mostly wilderness until the end of the 1800s, so analogous to the Big Thicket [in Texas]. There are still several million acres of flooded bottomland hardwood forest in the lower Mississippi River Valley, and probably the single highest biodiversity indices, as well as biomass production. The Mississippian civilizations arose here; Poverty Point mound civilization, living with and off the untold millions of waterfowl and fish and etc. and so forth.

The point is that the region has been all but forgotten by most conservationists – sort of like living in Brazil and forgetting the Pantanal or whatever. The Mississippi, White, Cache, Pearl and other rivers are still free-flowing and undammed. There are still virgin canebrakes (bamboo forests) on private land. I’m already getting a bit impatient at urbanites who pay attention to areas only when Audubon or the Conservancy make them into big destinations. I wrote about listening to local voices in my book on Honduras. Almost no one does that here.

3. Accomodating a “magnificent misanthrope”

The White River flows south, joining the Arkansas just above its junction with the Mississippi in the middle of a huge roadless area comprising some 125,000 acres, much of it still in private hands. The White River National Wildlife Refuge (NWR) stretches north along the river from there, joining with the Cache River and its attendant NWR just south and for many miles north of Interstate 40. It was to the latter location that Mark and family headed last Saturday after motoring up the fabled Highway 61, unable to simply cross the river at Rosedale due to the State of Arkansas’ atavistic dislike for Progress.

As his e-mail indicated, the verified ivorybill sightings reported in Science were all along the Cache River, within a very short distance of the interstate. The U.S. Fish and Wildlife Service folks at the Cache River NWR were very forthcoming and were able to answer all his questions, he said: he and his family were virtually the only visitors to arrive there all day. The wildlife refuge had designated special observation points beyond which it intends to restrict access – 5,000 of the refuge’s 60,000 acres have been closed. All the high officialdom were there, braced for an onslaught of crazed birders that never happened. It seems the word had gone out over birders’ listserves to stay home and leave the ivory-billed woodpecker in peace.

The only problem, Mark said, is that no one really knows what disturbs an ivory-billed woodpecker. Various theories are circulating about why the bird has proved so darned elusive for the last half-century. Perhaps, as my brother Steve suggested last week, it has learned and inculcated in its young an extreme wariness toward human beings – “a magnificent misanthrope,” he called it. Mark replied that this seemed plausible – at least based on his experience with some rare birds and mammals in Central America – but added that the White River area, which is now presumed to harbor a breeding population of ivorybills, is formidably remote and difficult of access. Ivory-billed woodpeckers don’t migrate, and the literature says that their breeding territories can be quite small for a bird of that size – no more than a couple square kilometers.

So presumably the male sighted up near I-40 is a dispersing juvenile looking for new territory. What makes this area attractive? It harbors the oldest known stand of bald cypresses in the United States, Mark said – trees over two thousand years old.

Mark went on to say that – contrary to the essay by John Fitzpatrick that I quoted here last week – the forests down there were never completely cut-over. According to the Cache River NWR managers, many patches of older forest remain, though none of them may be “virgin” – the oaks, pines and other valuable trees were, indeed, all taken at some point, but many stands of bald cypress and black gum were not. Thus, the ivorybill probably never ran out suitable nesting trees.

The limiting factor, then, back during the most severe bottleneck period following the end of the timber boom, would have been food. As a woodpecker, the ivorybill has a very high-protein diet (though it does eat lots of fruit, too). According to stomach-content analyses performed in the early 20th century, most of its protein was derived from one family of insects – longhorn beetles. The larvae of these beetles live in the wood of standing dead trees, including oaks and pines – the species that were high-graded out of the swamps some eighty years ago. There must have been some awfully lean years for an awfully small and secretive remnant population of ivory-billed woodpeckers.

Now these trees are recovering – and even better, they’re dying and being left to rot in place rather than being “salvaged,” as would probably happen if it were a Pennsylvania state park or forest. Mark noted that floods and beavers are part of the natural disturbance regime of Mississippi floodplain forests; high waters regularly kill pines and oaks without bothering the true swamp species – cypress and black gum. The NWR managers told him that they adopt a passive management approach to reforestation. The Cache River website lists “Protect and restore the bottomland hardwood resources of the basin” as one of the four, main Refuge Objectives. Management Tools include public hunting and “Water management for waterfowl, wading and shore birds.” In Dahomey NWR on the Mississippi side, Mark said, this includes the occasional dynamiting of beaver dams.

This area of Arkansas – the Big Woods – is wild. It’s home to a healthy population of black bear, and panthers are moving in. The human population is low and dropping at about ten percent a decade, Mark said. The Fish and Wildlife Service people told him that the local reaction to news of the ivorybill’s rediscovery seemed mostly positive, and this isn’t surprising – wildlife watching, hunting and fishing already make a substantial contribution to the local economy. It’s a myth that public opinion changes more slowly in rural areas than in supposedly more progressive urban and suburban areas, Mark said.

4. Disturbing conclusions

Lessons for conservation elsewhere may be more elusive than either Gene or I were originally willing to acknowledge. The fact is, every bioregion is unique; ecologists have learned the hard way that forest succession in the east, where most canopy replacement occurs as a result of single-tree or small stand mortality, is more the exception than the rule. The so-called edaphic climax model first developed in the northeast United States still seems to be a pretty good fit for our region. But in areas of complex physical geography like the Appalachians, natural disturbance regimes may change radically over very short distances – nothing like the broad, virtually flat and geologically uniform floodplain of the Mississippi. And while we do have a few possible old-growth obligate species, present or extirpated – northern flying squirrel, pine martin, sugar maple longhorn beetle – the list is much longer for species that simply do best in mature forests, or in forests with many old-growth characteristics. Features such as standing dead timber, downed woody debris, multiple age classes – including many 150-year-plus specimens – and a healthy humus layer provide optimal habitat for many of Penn’s Woods’ most treasured species, including: winter wren, Acadian flycatcher, black-throated green warbler, blackburnian warbler, magnolia warbler, Swainson’s thrush, brown creeper, blue-headed vireo, cerulean warbler, yellow-bellied flycatcher, brook trout, goshawk, barred owl, fisher and lynx; many slow-dispersing spring ephemeral wildflowers, such as painted trillium and dwarf ginseng; most lungless salamanders, which can take over a hundred years to re-colonize a clearcut; and unknown numbers of native ferns, mosses, liverworts, lichens, fungi and invertebrates.

Actually, this situation is not atypical of forest ecosystems anywhere in the world. At least among charismatic megafauna, the number of species completely intolerant to human disturbance is very small, but the number that depend on the continuation of something very like what they evolved in is – as one would expect – very large. Many advocates for the timber industry like to point to studies that show edge and early-succession species declining, but in some cases these are species native to the Midwest whose ranges have expanded only in recent times as the land was cleared. In other cases they are species that might have been naturally rare, dependent on natural clearings resulting from the occasional stand-clearing ice storm or tornado.

Concerns about balancing the needs of humans with those of other animals are very appropriate. By why should one species monopolize 90 percent of natural resources and dominate virtually every bioregion? There’s something awfully depressing about the idea that every species and natural community on the planet persists only because human beings have decided they can tolerate its presence. This is a far, far cry from the view of Creation expressed by the Voice out of the whirlwind in the Book of Job. To pretend that we can and should manage all of nature is sheer hubris. And a narrow, species-by-species approach to conservation not only misses the larger picture, it ignores the magnitude of what we have lost in terms of sheer plant and animal biomass. The forests of pre-Columbian North America – lightly managed by human beings for millennia, mostly through fire – teemed with wildlife. Seventeenth-century explorers and settlers were nearly unanimous in their astonishment at the great numbers and diversity of fish, foul and game, even though to some it seemed forbidding, a “waste and howling wilderness.” Somewhere along the line, the Biblical vision of wilderness as a place of testing and transformation had been replaced by a fear and hatred of the untamed that haunts us to this day.

Everyone likes nice, park-like woods with great big trees and very little messy understory. Pure stands of old-growth hemlock or spruce can certainly inspire reverence, but they don’t come close to satisfying the ecological definition of old-growth, which includes trees of all ages and conditions – and much more besides. Conservationists err in putting too much emphasis on protecting stands of big trees and not enough on the need to recover old-growth forested landscapes – the natural condition for at least ninety percent of Pennsylvania and most other eastern states.

How much old-growth does wildlife need? All it can get. We need to relearn humility and begin to heed that Voice out of the whirlwind. We need to welcome natural disturbances and recognize them as blessings in disguise rather than “natural disasters” ripe for “salvage.” Many more insect outbreaks and some wildfires on public land could be allowed to run their course. Public and private land managers could do a much better job at grouping and connecting stands of “legacy trees” within timbered areas. Herpetologists tell us that uncut buffers around wetlands of all kinds should be measured in the hundreds of yards rather than in the tens or hundreds of feet, as is currently the practice (if we’re lucky). Most forested headwater areas should never be cut to protect hydrology and downstream organisms, such as our increasingly beleaguered native mussels. And all this presumes success in controlling the biggest on-going scourges of Pennsylvania forests: white-tailed deer overbrowsing, air pollution (including acid rain), and fragmentation from roads and sprawl. I don’t think any of these problems are anywhere near as severe in the Big Woods of Arkansas. But unless and until we address them, biodiversity here will continue to decline.

One way or another, it’s almost a given that Coyote – patron of unforeseen consequences – will have the last laugh.
__________

UPDATE: Mark just e-mailed me with a couple corrections (which I have made), and added the following thought:

The geography of the lower Mississippi valley alluvial swamps (bottomland hardwood forests) is similar in character to the varzea of Amazonia, though of course with the leveeing of the Mississippi River and side rivers, flooding is not nearly as extreme as it once was. However, the geomorphology is very similar, and includes huge oxbow lakes – the largest in the Americas north of Amazonia are in the Delta.

My point is that humans have lived and farmed Amazonia, and seasonally the varzea forest, for millennia, using swidden rotation (slash and burn) which involves small clearcuts. This does not mean the Amazonia (or the Peten in Guatemala, for that matter) are “second-growth”; it means that human populations are low enough that human disturbance regimes are simply another form of forest modification. Indeed, swidden, the world’s oldest form of agriculture (or horticulture), is successful in that it mimics natural treefall dynamics, widely believed to be the disturbance regime that is most important in helping create the awesomely high biodiversity of the Amazon.

When human populations swell and elite/capitalist greed enter into the equation, forests are wiped out. It is all in the temporal and spatial scale at which the destruction is taking place, however: this can quite rapid, or over decades or even centuries. Essentially, does the local human population absolutely depend on a healthy ecosystem, or not? Economics and governance are at the heart of it.

The finding

holloway overhung with ancient trees n Cornwall

Stop this chattering
about what it means, or
might mean. When you first
heard the news, what
was your reaction? Deafness.
Two mornings ago
I played the strange phone
message from
my brother in
Mississippi – Don’t know
if y’all heard yet, but they’ve
discovered the [….]
right across the river
from Rosedale
– heard
the tremor in his voice,
but my mind, fearful
daylight creature, failed
to fill in the blank.
I listened again: still
couldn’t make sense
of it. Oh
well,
I thought, probably
some archaeo-
logical thing.
And didn’t give it another
thought until mid-
afternoon, when
my other brother sent
around the link. Ivory-billed
Woodpecker Rediscovered.

I would like to
be able to say that I
got up then & wandered
outside to listen
to the birdsong, aware
suddenly of all the notes
inaudible to the human ear.
Perhaps I did sit
a little straighter
in my chair. I kept reading
e-mail, & at some point
I found myself shaking
with silent sobs. I wrote
in my blog. I grabbed
a beer from the fridge.

The next day when
I played that phone
message for
the third time, it was
perfectly comprehensible.
The Ivory-billed. What else
have I failed to hear because
I was trying too hard
to fill some blank that
was never really blank?
Today
I’m off to
a cousin’s wedding
& for once I’m not
thinking gloomily about
what world their likely kids
will find themselves in.
All might
not yet
be lost. It’s raining,
it’s April, &
the goddamn birds
are singing like
there’s no tomorrow.

Falconiform

holloway overhung with ancient trees n Cornwall

At ease, lieutenant.

Thank you, sir.

I understand you’ve been able to keep all the runways free of pigeons for the last week with just two birds.

Yes, sir.

How is that possible? Do they really kill that many pigeons?

No, sir. They haven’t killed more than half a dozen. What happens is that the regular presence of a hawk or falcon completely traumatizes a local prey population. They either lie low, only venturing a few feet from cover, or they move somewhere else entirely.

Kind of a shock and awe thing, then?

Yes, sir. (To incoming falcon) Here we go. Good boy! (Falcon lands on glove. The falconer deftly secures the leather straps around its feet and slips a hood over its head.)

What – what’s the hood for?

Oh, it just keeps them tractable, sir. They’re very high-strung. The very thing that makes them such effective killing machines – that single-minded intensity – makes them less than ideal pets, I’m afraid.

Not something I’d want my five-year-old to play with, eh?

No, sir!

Now, what species is this one here? Is this a peregrine?

Its daddy was a peregrine, yes sir. But it’s a hybrid: its mother was a merlin.

How is that possible? Artificial insemination?

Yes, sir.

They must be quite valuable, then.

Yes, sir. I wouldn’t be able to afford them if I didn’t breed them myself.

Oh, really? Do you mind my asking how you do that? I mean, I grew up in cow country, I know how they do it with bulls…

(Chuckles.) Well, sir, it’s a little different, I think. I have a special hat that I wear…

Shaped like a female falcon, I suppose?

Well, no, sir, that isn’t necessary. I use the same hat for all my birds – everything from kestrels to red-tail hawks. See, the kind of visual cues they respond to are more motion-oriented, just like they won’t go for a pigeon unless they see it fluttering or walking around.

So you put on this special hat and you, um…

I initiate courtship, sir. (Chuckles.) I do exactly what a sexually receptive female of their own species would do: about five minutes of head and torso bobbing, like this, then…

(Incredulously) They mistake you for a female falcon? I thought these birds were considered highly intelligent!

They have just enough brains to do what nature designed them to do, sir. Find the target. (Continues miming falcon courtship display.)

Thank you, that’s enough, lieutenant.

Yes, sir.

Carry on, then.

Yes, sir. (Salutes, keeping left arm horizontal. Falcon swivels its hooded head and clicks its beak.)

The origin of the chickadee

holloway overhung with ancient trees n Cornwall

Once there was a woman who had a daughter she treated badly. The mother would be boiling corn soup and she would make the girl stir and stir. She would look in the pot and see it there and go hungry. But when she asked for some, the mother always said, “Not yet.” There never seemed to be a time when the corn soup was ready. The poor girl wished she could be a bird and fly away. Her wish was granted, and They turned her into a chickadee. That’s why the chickadee always comes around when people have anything going on. It hopes they will give it corn soup. It follows you through the woods, too, when you go to cut logs or brush, think maybe you’re going to build a fire and make soup.

Seneca Indian story collected by Merle H. Deardorff at the former Cornplanter Grant, NW Pennsylvania (destroyed by the Kinzua reservoir in 1965)

The strange soundtrack of home

holloway overhung with ancient trees n Cornwall

“Suddenly, subtle variations in the tone and rhythm of that whistling phrase seem laden with expressive intention, and the two birds singing to each other across the field appear for the first time as attentive, conscious beings, earnestly engaged in the same world that we ourselves engage, yet from an astonishingly different angle and perspective.”
David Abrams (see extended quote at end of post)

Living out here in the woods as I do, it’s sometimes easy for me to forget just how strange I’ve become. I read the above quote and thought, “What does he mean, ‘for the first time’? Doesn’t everybody hear bird songs that way?” But apparently most people’s first reaction is to think of birds as pre-programmed music boxes – when they hear them at all. Many folks, of course, don’t have the luxury of waking up and falling asleep to the songs of birds as I do (although there is an interstate highway right over the ridge, and it can be pretty loud sometimes). I guess it also helps that I spent my teenage years listening to 20th-century and avant-garde classical music, which was probably pretty good preparation for appreciating natural sound. The really weird thing is that I used to be a total music junkie, but over the last several years, without ever consciously intending to I’ve become so attuned to natural sounds that I find it difficult even to listen to recorded music for longer than a half-hour at a stretch.

For a fan of natural soundscapes, the months of May and June represent the year’s musical climax. Many mornings I’ll forgo an extra hour of sleep just so I can be out on the porch by first light. The dawn chorus begins a few minutes after 5:00 with the first tentative calls from song sparrow, titmouse and cardinal – the same birds that anchor the avian chorus in January. Almost immediately, however, a wood thrush tunes up, joined by a great-crested flycatcher and a common yellowthroat. Over the next two hours, these calls will be blended with a number of others: phoebe, red-bellied woodpecker, field sparrow, catbird, red-eyed vireo, Baltimore oriole, scarlet tanager, towhee, pileated woodpecker. A background of more-or-less continual chips and buzzes from chipping sparrow, worm-eating warbler and other more distant, interior forest species such as the cerulean warbler and ovenbird, makes up a sort of sonic horizon or drone effect.

But it’s the wood thrush’s song that, for me, provides the main focus of musical interest. Though less ethereal than the call of its close cousin the hermit thrush, the wood thrush’s song is variable enough to hold my attention for many hundreds of bars. The Cornell Lab of Ornithology’s website – which include a wav file of the sound recording – describes it as follows:

Wood Thrushes are justly famous for their beautiful flute-like voices that may combine two notes at one time. The song is composed of three distinct parts. The first, often inaudible unless the listener is close, consists of two to six short low-pitched notes such as bup, bup, bup. The middle part is a loud phrase often written ee-oh-lay, and the final part is a sometimes ventriloquial, trill-like phrase made up of nonharmonic pairs of notes given quite rapidly and simultaneously. Each bird has a repertoire of songs based on combinations of variations of the three parts, and the songs are often repeated in order. The bup, bup, bup phrase is also heard as a call, which is given louder and at a greater frequency when the bird is agitated.

I’m not sure I agree with the cliched comparison to a flute. What they call the second and third parts combine woodwind and bell-like qualities. Setting aside the introduction and considering the rest of the song as one unit, I particularly admire the way the thrush modifies the bittersweetness of the main melodic lines with a shifting array of grace notes. These strike me as more light-hearted afterthoughts. A rough translation of thrush song might be something like, “The world can break your heart, you know. Drink up!”

We are blessed with the presence of this archetypal Neotropical migrant for barely three months of the year. Like the scarlet tanager and the cerulean warbler, its population has been steadily declining in recent years, due mainly to the loss and fragmentation of suitable nesting habitat by roads, highways and suburban and exurban sprawl. Last year, especially, thrush numbers seemed to be down here in Plummer’s Hollow, but this year they appear to have rebounded – at least around the houses. The old tenant house where I live apparently straddles the border between territories of two male thrushes, which means that I always have one if not both singers well within earshot.

*

It was bioacoustician Bernie Krause who first documented the existence and integrity of natural soundscapes, which he likens to symphonic compositions. (I prefer to think of them more as jazz improvisations, given that neither a composer nor a conductor is in evidence.) Krause discovered through studying sonograms that every song or call occupies a distinct aural niche. He hypothesizes that, as part of their adaptations to (and alterations of) specific habitats, species adjust their calls so as to complement rather than to compete with the calls of other species. This seems highly plausible, especially where passerines are concerned, since there is such a high degree of flexibility in the way they learn and transmit calls. As Krause and other birdsong collectors have found, calls can vary considerably within a species, displaying not only regional and local ‘dialects,’ but individual signatures as well. (The better part of these differences will be inaudible to humans.) One can easily imagine subtle shifts in songs as new aural niches open or close due to slow, bioregional shifts in ecosystem composition.

My friend the Sylph e-mailed late last week with a query about the mockingbird that had kept her awake the night before. (I’m not quite sure why listening to the mockingbird go on and on and on prompted her to think of me!) “What’s the source of their ‘creativity’?” she asked. “Do they remember songs of other creatures? Or are they just wired to improvise or mimic? The various riffs were in mostly threes and twos and the songs were not just of other birds but also frogs. So what’s up with the mockingbird?”

I said it’s uncertain how and whether creativity is “wired,” for mockingbirds as for other sentient species (including humans). There’s little doubt that some birds possess good memories – far better than humans, in fact. Although a few scientists do still believe that episodic memory is unique to humans, behavioral experiments with seed caching species such as Western scrub jays “show evidence in birds of mental time travel both backward and forward,” as Science News reported back in February. (Susan Milius, “Where’d I Put That? Maybe it Takes a Bird Brain to Find the Car Keys,” Vol. 165, 103-105.)

As for mimicry, the term itself carries unwarranted connotations of mechanical imitation, denying the considerable role of intelligence in shaping the calls of highly innovative species such as mockingbirds, catbirds and brown thrashers. And if we accept recent findings about mimicry, it seems to me that almost all passerines may be considered mimics to one degree or another. That is to say, everything they sing has been learned, not simply inherited, though it’s true that most seem predisposed to learn the songs of their own species. One set of experiments with juvenile white-crowned sparrows showed that they will learn the songs of whichever species they are caged with, which included tutors from a quite distantly related, Asian species, the red avadavit (yes, that’s really its name!). One of the birds most prized for its ability to mimic human speech in captivity, the hill mynah, doesn’t imitate other species in the wild at all. However, its calls do display distinct variations in dialect over quite short distances, which leads me to suspect that its extreme vocal flexibility represents an adaptation to a highly variable native soundscape.

Other experiments have substantiated fears about the effects of anthropogenic noise on birdsong transmission. The harmful “edge effects” of the interstate on the other side of the ridge from me include not only increased depredations of edge-dwelling predators, but severe impairment of avian soundscapes, as well. For many songbirds – especially interior forest specialists with relatively quiet calls – highway noise can disrupt courtship and territorial singing for hundreds of yards in either direction. And even when courtship and breeding are successful, researchers have discovered, quite often the young adults can’t properly learn their species’ songs. Birds raised near highways may be unable to defend a territory or attract a mate, because their songs are too incomplete – or may be missing altogether.

*

The Acoustic Ecology Institute website archives a number of great essays on soundscapes. (However, the site evidently hasn’t been updated for some time; it contains a few broken links.) I’ll close with a fairly lengthy selection from David Abram’s The Spell of the Sensuous: Perception and Language in a More-than-Human World (Pantheon Books, 1996) – an excellent read, by the way. According to Abrams, human beings are mimics par excellance.

Humans are tuned for relationship. The eyes, the skin, the tongue, ears, and nostrils–all are gates where our body receives the nourishment of otherness. This landscape of shadowed voices, these feathered bodies and antlers and tumbling streams–these breathing shapes are our family, the beings with whom we are engaged, with whom we struggle and suffer and celebrate.

For the largest part of our species’ existence, humans have negotiated relationships with every aspect of the sensuous surroundings, exchanging possibilities with every flapping form, with each textured surface and shivering entity that we happened to focus on. All could speak, articulating in gesture and whistle and sigh a shifting web of meanings that we felt on our skin or inhaled through our nostrils or focused with our listening ears, and to which we replied–whether with sounds, or through movements or minute shifts of mood. The color of sky, the rush of waves–every aspect of the earthly sensuous could draw us into a relationship fed with curiosity and spiced with danger. Every sound was a voice, every scrape or blunder was a meeting–with Thunder, with Oak, with Dragonfly. And from all of these relationships our collective sensibilities were nourished.

Today we participate almost exclusively with other humans and with our own human-made technologies. It is a precarious situation, given our age-old reciprocity with the many-voiced landscape. We still need that which is other than ourselves and our own creations. We are human only in contact, and conviviality, with what is not human. . . . We need to know the textures, the rhythms and tastes of the bodily world, and to distinguish readily between such tastes and those of our own invention. Direct sensuous reality, in all its more-than-human mystery, remains the sole solid touchstone for an experiential world now inundated with electronically-generated vistas and engineered pleasures; only in regular contact with the tangible ground and sky can we learn how to orient and to navigate in the multiple dimensions that now claim us. . . .

If we listen, first, to the sounds of an oral language–to the rhythms, tones, and inflections that play through the speech of an oral culture–we will likely find that these elements are attuned, in multiple and subtle ways, to the contour and scale of the local landscape, to the depth of its valleys or the open stretch of its distances, to the visual rhythms of the local topography. But the human speaking is necessarily tuned, as well, to the various non-human calls and soundings that animate the local terrain. Such attunement is simply imperative for any culture still dependent upon foraging for its subsistence. Minute alterations in the weather, changes in the migratory patterns of prey animals, a subtle shift in the focus of a predator–sensitivity to such subtleties is inevitably reflected not just in the content but in the very shapes and patterns of human discourse.

The native hunter, in effect, must apprentice himself to those animals that he would kill. Through long and careful observation, enhanced at times by ritual identification and mimesis, the hunter gradually develops an instinctive knowledge of the habits of his prey, of its fears and its pleasures, its preferred foods and favored haunts. Nothing is more integral to this practice than learning the communicative signs, gestures, and cries of the local animals. Knowledge of the sounds by which a monkey indicates to the others in its band that it has located a good source of food, or the cries by which a particular bird signals distress, or by which another attracts a mate, enables the hunter to anticipate both the large-scale and small-scale movements of various animals. A familiarity with animal calls and cries provides the hunter, as well, with an expanded set of senses, an awareness of events happening beyond his field of vision, hidden by the forest leaves or obscured by the dark of night. Moreover, the skilled human hunter often can generate and mimic such sounds himself, and it is this that enables him to enter most directly into the society of other animals. . . .

If one comes upon two friends unexpectedly meeting for the first time in many months, and one chances to hear their initial words of surprise, greeting, and pleasure, one may readily notice a tonal, melodic layer of communication beneath the explicit meaning of the words–a rippling rise and fall of the voices in a sort of musical duet, rather like two birds singing to each other. Each voice, each side of the duet, mimes a bit of the other’s melody while adding its own inflection and style, and then is echoed by the other in turn–the two singing bodies thus tuning and attuning to one another, rediscovering a common register, remembering each other. It requires only a slight shift in focus to realize that this melodic singing is carrying the bulk of communication in this encounter, and that the explicit meanings of the actual words ride on the surface of this depth like waves on the surface of the sea.

It is by a complementary shift of attention that one may suddenly come to hear the familiar song of a blackbird or a thrush in a surprisingly new manner–not just as a pleasant melody repeated mechanically, but as active, meaningful speech. Suddenly, subtle variations in the tone and rhythm of that whistling phrase seem laden with expressive intention, and the two birds singing to each other across the field appear for the first time as attentive, conscious beings, earnestly engaged in the same world that we ourselves engage, yet from an astonishingly different angle and perspective. . . .

From such reflections we may begin to suspect that the complexity of human language is related to the complexity of the earthly ecology–not to any complexity of our species considered apart from that matrix. Language, writes Merleau-Ponty, “is the very voice of the trees, the waves, and the forests.”

As technological civilization diminishes the biotic diversity of the earth, language itself is diminished. As there are fewer and fewer songbirds in the air, due to the destruction of their forests and wetlands, human speech loses more and more of its evocative power. For when we no longer hear the voices of warbler and wren, our own speaking can no longer be nourished by their cadences. As the splashing speech of the rivers is silenced by more and more dams, as we drive more and more of the land’s wild voices into the oblivion of extinction, our own languages become increasingly impoverished and weightless, progressively emptied of their earthly resonance.

The way of a naturalist

holloway overhung with ancient trees n Cornwall

Idries Shah’s observation that humility is not merely a virtue but a technical requirement points to the deep kinship between authentic self-knowledge and empirical knowledge about the so-called mundane world. (See the quotes from conservation biologist Reed Noss from one of the entries on December 17.) Islamic mathematicians, geographers and scholars of a thousand years ago made much of this kinship, of course; when Western European naturalists picked up the torch half a millennium later, however, initial allegiance to a kind of decayed theosophy quickly faded. For whatever reason, the greatest revolution in human thinking the world had ever seen bequeathed to us the modern view of a universe in which almost everything is dead, inert, or at best robotic. Despite ample evidence to the contrary, the majority of behaviorists continue to assert that only humans possess “consciousness” (continually redefined to exclude other species that are strongly suspected to dream, anticipate, mourn the dead, experience joy, etc.). Even fellow humans can be shown to operate mostly on the basis of self-centered urges and instincts. It is commonplace to speak of DNA as “programming” – never mind that this completely ignores the role of chance (or God, if you prefer) in shaping all outcomes.

Originally an elite, minority view, this way of looking at the world has become dominant even among those who consider themselves to be most in revolt against modernism (or postmodernism, which is a fairly undistinguished offshoot in my opinion). “Scientific creationism” is an obvious example. But I would go even further: I don’t believe there’s any evidence that literalistic interpretations of religious texts and traditions held any sway before the modern era. Yet today such interpretations are at the root of a worldwide phenomenon – religious fundamentalism – and it isn’t hard to see why. Humans are an intensely visually oriented species; the overwhelming material and technical elaboration of modern societies and the raw power that that confers adds up to an argument that is extremely difficult for the adherents of more traditional worldviews to confront head-on. Even without the direct experience of conquest and slavery or debt-peonage, folks living more-or-less contentedly for centuries on subsistence and gift economies now suddenly understand themselves to be impoverished. Lacking. Inadequate and inferior. (Helena Norberg-Hodge writes movingly about observing this process in the kingdom of Ladakh, where India has been the direct source of the modernist malaise, in her book Ancient Futures.)

A generation or so later, the reaction sets in. But power once gained is difficult to give up, and where the modernist project is concerned that power is expressed in stark, shameless reductionism. The world is nothing more than a grab-bag of resources to be exploited for human use; human beings are nothing more than consumers/taxpayers/voters whose well-being derives ultimately from adequate access to resources. Fundamentalists – be they Christian, Muslim, Ultra-Orthodox Jewish, Hindus, even American Indian – in asserting the validity of their own traditions, attempt to exploit the power of reductionism rather than to challenge its primacy. (They are after all reactionaries, not radicals.) The materialist’s simple-minded dichotomy opposing objective, concrete reality to subjective, imaginary interpretation – “just the facts” vs. “just a myth” – has already insinuated itself into their thoughts and their language.

But all this has been a digression from what was to have been my main topic today. I want to look at a few of the ways in which a modern scientist might cultivate what a Sufi (or Zennist, or Christian mystic) would recognize as authentic ways of knowing. Our guide will be the late Lawrence Kilham.

Lawrence Kilham was a distinguished virologist who also wrote extensively about woodpeckers and crows for the ornithological journals. He is a relatively rare example of a laboratory scientist who also honored – and employed – the skills of a field naturalist. (As most readers are probably aware, the culture of modern science fetishizes laboratory work and, even more, the ‘pure’ theoretics of physics; biologists who engage in such lowly tasks as observation and systematics are near the bottom of the totem pole, along with anthropologists and other unworthy aspirants to the testosterone-charged arenas of Pure or Hard Science.) In the introduction to The American Crow and the Common Raven (Texas A&M Press, 1989), Kilham discusses the kinds of intellectual tools necessary for the scientific enterprise, mostly by quoting others. (Honoring the chain of transmission, as a Sufi might say.) Here, in quoting Kilham, where he simply lists author and date in parentheses, I’ll include the titles of the works referenced.

“‘Each scientist,’ wrote Agnes Arbor (The Mind and the Eye, 1954), ‘should be able to say to himself, like Descartes, that his intention is to build upon a foundation that is all his own.’ This may seem difficult when one is starting out, but it is the only way likely to be enjoyable. There is no such thing as one scientific method that all must follow (J.B. Conant, Two Modes of Thought, 1964). As Nietzsche said of philosophy, ‘This is my way. What is yours? As for the way, there is no such thing.’ Each must find or invent techniques best suited for his individual approach.’ . . .

“Preferring to be a free agent, I have always shunned the idea, whether with birds or viruses, of starting with a hypothetical problem and sticking to it. The challenge is to get from the known to the unknown. Almost any problem can set the wheels in motion. But once under way, I know I can do best by observing all that birds do, taking notes, then reviewing and reflecting on them when I get home. Persisting in this pedestrian fashion I find that something exciting almost always turns up. It is the chance discovery that makes science exciting. As [Konrad] Lorenz (Studies in Animal and Human Behavior, 1970) states in a chapter entitled ‘Companions as Factors in the Bird’s Environment,’ ‘The factual data upon which all of the following investigations are based derived almost entirely from chance observation.’ The chance experiment, he thinks, assures an impartial observer freedom from any initial hypothesis. I have long found such ideas congenial. They echo Louis Pasteur’s dictum, enshrined at the Harvard Medical School . . . that ‘chance favors the prepared mind.’
(Kilham, The American Crow and the Common Raven, 5-6. Emphasis mine.)

Whether in the lab or in the field, Kilham preferred to keep it simple: “I like to work with a minimum of apparatus,” he admits, and quotes Rousseau: “The more ingenious and accurate our instruments, the more unsusceptible and inexpert become our organs: by assembling a heap of machinery about us, we find afterwards none in ourselves.”

For behavioral studies in particular, Kilham says, “All one needs is a pair of field glasses, a notepad, and an open mind. One cannot, at least I cannot, study bird behavior and be occupied with a complicated piece of apparatus. Observing is a full-time occupation. You have to have your mind on what you are doing. Important bits of behavior – a copulation, a glimpse of a passing predator, or something new and unexpected – can take place in seconds. If one’s mind is on a camera, wondering how to get a good picture, one’s mind is not on what a bird is doing; being a good photographer is also a full-time occupation.” And he goes on to describe how one attempt to bring a tape recorder into the field caused him to miss a distressing amount of crow behavior.

“If one concentrates on producing a statistically sound publication, one may overlook much of what the birds are doing. Emphasis will be on covering as many nests or pairs as possible. But in trying to study birds as whole, living entities, noting everything they do, I find that two pairs of woodpeckers or, with crows, two cooperatively breeding groups, is the maximum I can study effectively. I am committed to this approach and thus feel that simple narration, or an anecdotal style, is the soundest way of presenting how animals live.” (Ibid, 7)

One problem with his kind of approach finding a wider acceptance among scientists, Kilham recognizes, is the mechanistic biases of the reigning “scientific” worldview. He quotes the ornithologist Olas Murie, who complained in a 1962 journal article that “we are extremely timid about assigning to other animals any of the mental or psychological traits of man. One would think that the scientist is the perfect fundamentalist, carefully maintaining a wall between man and other animals.”

The problem is that individual observations are hard to quantify. Even the most fascinating or tantalizing observation is likely to be dismissed by the worshippers of Hardness and Purity as anecdotal. Kilham again quotes Lorenz to the effect that the supposed centrality of quantitifiable methods is “one of the dangerous half-truths which fashion is prone to accept.” “The fallacy,” Kilham adds, “is what the philosopher Alfred North Whitehead referred to as ‘the fallacy of misplaced concreteness.'” He quotes a biologist named Donald Griffin, who thinks that the mechanistic view of nature is in error not only “because it belittles the value of animals, but because it leads us to a seriously incomplete and misleading picture of reality.”

After a paragraph on statistics and its lack of utility in either of the disciplines which formed his life-work, Kilham concludes, “There is much that is enjoyable in thinking for oneself and studying birds in one’s own way. Few seem to realize that even an ordinary person can make discoveries. The hitch is, as Polanyi (The Study of Man, 1959) pointed out, that ‘you cannot discover or invent anything unless you are convinced that it is there ready to be found. The recognition of this hidden presence is in fact half the battle. It means that you have hit on a real problem and are asking the right questions.’ This book is mainly an account of my search for the ‘hidden presence’ in crows and ravens. There has been no magic involved. Only the thousands of hours of watching, none of which has been dull.” (Ibid, 9-10. Emphasis added.)

We might argue with Kilham’s limited definition of magic, but never mind. The immense significance attached to birds in many different cultures is another topic to reserve for fuller treatment some other time. But I can’t resist closing once again with the motto to Blake’s The Marriage of Heaven and Hell (invoked also in one of the foundational entries for this weblog):

How do you know but ev’ry Bird that cuts the airy way,
Is an immense world of delight, clos’d by your senses five?