Corvus (23 page)

By Thursday she’s changing and I sense that the mood of spring, which has contained her so totally, is ebbing. When I get back from work in the mid-evening, she calls to me as soon as she hears the sound of the key in the door. She potters now between her nest and her house. Something feels different. I leave her nest alone for the moment, resisting the urge to tidy it away. When she comes to talk to me, her voice is no longer harsh.

It’s as well that I leave the nest alone because her return to the usual recognisable rook is temporary. Within a day she’s gone to sit under the table again, expanding her nest this time, tearing madly, leaving trails of newspaper between study and kitchen. She is no longer willing to return at night to the favela house. She is uncommunicative. She does not call early in the morning. I come downstairs to a small black shape on the carpet, to a grey face peeping from a cloud of newspaper, over the strut of the chair.

Over the next week, there are five more eggs. She sits, flattened to the ground, asking to be hand-fed, snoozing, head under wing. Again, she doesn’t sit on her eggs as she should to warm and incubate them towards hatching. I leave them as they lie, cooling, until after a few days I pick them up. She knows, but she does not know. The behaviour is impelled by something beyond herself. Perhaps she knows they will not hatch. I put the eggs with the other one on the plate, a small, perfect still-life. I would like to paint it but lack the skill to make it as beautiful as it is.

And then suddenly she changes again. It is Friday morning and with swift and comprehensive suddenness she seems bored by the sitting. She spends less time under the table and no longer snaps when I extend a hand towards the outer fringes of paper. She leaves her nest and when I begin, experimentally, to remove the paper, she doesn’t try to defend it, doesn’t shout and run at me. For a time she wanders between rooms. I remove the paper, a handful at a time. I wait between handfuls. She comes back and looks but is no longer concerned. I continue until it is cleared away, until I can vacuum the crumbs and leftover crusts of bread and butter, the scraps of dried avocado and egg yolk, and scrub the carpet. Chicken seems disorientated, purposeless, perhaps the way we all feel on returning to ordinary life after a removal from our quotidian routine, being unwell or away on holiday, even for a couple of days, when on returning we have, with unexpected care and attention, to reconstruct the small components of our lives. She follows me, keeping me close.

During the remaining days of March, the early ones of April, I
watch her, sit with her on my knee, trying to judge what the season’s activities have meant, whether she’s changed, whether something of the spring has imprinted its losses, its deficits upon her. I do not know if I am able to tell.

Over the next few days, she returns to herself and to me. By the first evening, she has come to stand on my knee again. I look at her long, banded black feet and nails against the fabric of my jeans. Over the evening, she sinks lower, warming my knee as she does so, head under her wing. She is even more affectionate than usual, sitting very close to me, preening my hair, calling again from the bottom of the stairs. She comes to stand beside me as I work, jumping onto my foot under my desk.

One afternoon, I can’t find her. I call and she calls back. She is behind a chair in the sitting room. She is bathing in the light from the sun through the front windows, wings spread, head to one side, with the deep and obvious pleasure birds derive from warmth and light. The preoccupations of sex and reproduction have yielded, abandoned their power over her. She is her own bird again, restored. Spring for Chicken is over. She seems content again to potter, to wander from room to room, to greet the morning with enthusiastic delight, the sun as it shines into the sitting room or onto her as she perches on her branch, to resume her bathing rituals and her evening habit of sitting on my shoulder as I read. The outer world is forgotten, extraneous, for this year at least, although it’s still only March. For the rest of us, spring has barely begun.

A couple of days later, the clocks move forward. We lose our
precious hour to cold, pale light. Chicken calls again, but now an hour earlier at the bottom of the stairs. From high ground above the city, everything seems wrapped around in chill, blue-grey mist. I look down on the canopies of trees, on dark smudges of nests among the branches, on rooks standing blackly, one by one, waiting, guarding.

A
mong the things of which we may be most afraid is the silence of birds. It foreshadows endings. It creates images of places despoiled, of habitats laid waste – oil slicks or poisoning by pesticide – of war and the threat of war, of destruction by heat or ice or water. The silence of birds is the absence of birds. Strip from each day, season, year, the presence of birds. Still the movement, stop the singing. In cities, the only natural sounds would be our own, our voices, the wind and rain. Birdsong is more than itself. It is not an addition, supplementary to the rest of our lives, pleasing but inessential; it is vital, necessary, for the sounds we hear daily are, at the very least, one marker, if not of our success then of our welcome failure, thus far, to complete our process of destruction. The title of Rachel Carson’s startlingly innovative, seminal work on the effects of artificial pesticides on the environment,
Silent Spring
, published in 1962,
shocks, for the terrible contradiction contained in those two words. An epigraph to the book quotes John Keats:

There are very few places on earth where birds do not live. Even in the quiet, unpeopled regions we think of as remote, as high or cold or hot, there are birds. In the peerless cold of the Arctic, horned larks and ravens live, snow geese and owls, terns, rock ptarmigans, longspurs; in the Antarctic, penguins, skuas, terns, albatrosses, sheathbills, petrels. In the highest mountains, the Himalayas, the Altai, there are birds: the snowcocks, Tibetan and Himalayan, Caucasian and Caspian; golden eagles and lammergeyers, griffons and ibisbills. In deserts, there are plovers and nightjars, sand martins and sandgrouse, ravens and roadrunners. In every place, bird voices carry over distance on iced or burning air.

The song of birds is integral to our lives, one component of the synaesthesia of memory, like music or scent or the sudden image flashing a synaptic instant of recall, a summer garden, a wood, a moor, a harbour. A sound catches at you. You hear by chance from the radio the booming chanting of the ground-hornbill, its strange, almost human cry: ‘Ing,’ it intones, ‘ing, ing, ing, ing,’ and you are standing again on the central African morning, in the blue-gum-fragrant heat of another time. The recorded voice of terns surrounds you suddenly with image, sensation, memory: of rocks, sand, lichen, the
crystalline emptiness of a Hebridean beach. The unfamiliarity of bird calls in another country can bring, as few other things, a realisation of the measure of distance.

As we sleep and as we wake, birds have slept and woken before us as the planet shades perpetually between darkness and light, latitude by latitude, the voices of birds rising and singing and ebbing back into night, like air-flows over the curvature of the earth, a never-ending curtain of moving sound.

Birds begin to sing at dawn, whether in the long, liminal polar dawn or the quick, brilliant dawns of the equator as the sky lightens before sunrise (the somnambulist’s night- or daymare, the first notes of the crazy optimist’s song from outside the window, the first intimation that attempts at sleep are pointless). It’s thought that at least some of the purposes of their song, the establishment of territory and the finding of mates, are given additional force by the exuberance of dawn birdsong, a song often markedly different from one sung later in the day, carrying further through still morning air. Different species of birds begin singing at different moments, a stepped choir of evolutionary organisation. As dawn is still too dark for effective food-searching, birds may use the time to re-establish territorial rights, singing their most elaborate songs to impress and attract mates, among them new migrators who arrive at dawn. They may sing too in a post-darkness burst of enthusiasm, an expression of pleasure or an affirmation of rights, a bird’s rare moment of dominion.

One year, when Radio 4 held a day-long celebration of spring, Dawn Chorus Day, we watched and listened as, one by one, tracing
morning across the globe, bird and animal sounds animated each of our birds, lit in them, if not a cultural memory, then a spirit of interest or perhaps of celebration, as, in a song-fest of multi-species enthusiasm, they joined with great northern divers and trumpeter swans, with tui birds and musician wrens, with birds of paradise and marsh frogs, in inimitable song.

Roger Deakin writes enchantingly in
Wildwood
of sleeping out in a rook-inhabited wood on a warm May night, of settling to sleep after the rooks and waking at dawn to layers of birdsong, robin, chiff-chaff and blackbird singing under the overwhelming sound of rooks. ‘I drifted back into consciousness to the most raucous of dawn choruses. It was still only ten past four.’

His descriptions of the sounds of beak and feathers, of mutterings and conversation, are as familiar to me as the sound of the voice at dawn. In this house, dawn, or at least the perception of dawn, has altered over the years, occurring now later than it used to. In her early years here, Chicken observed the rules of the natural world more strictly (as she still does on other matters), and dawn was dawn. It wasn’t long after she came here that we learnt the daybreak singing habits of the rook, although we were lucky. She was never the earliest of her kind as she didn’t call much before 4 a.m. and even then it was only on the light mornings of summer. Mostly, she called around five. We became used to it, the voice reaching us through layers of sleep. Now though, as she’s grown older, Chicken likes to stay in bed, or rather on branch, later than she used to, particularly in winter, reluctant, as we all may be, to start the day in darkness. She’ll respond to hearing the radio switching
on upstairs by calling from her house as she wakes. After a short while though, bored by waiting for company, she’ll come to stand at the bottom of the stairs as she’s always done, calling to admonish or encourage. Her morning call is a regular rook ‘caw’, the sound we characterise as
aaarkh
!
(our attempts at transliteration being primitive). Chicken reacts to what she regards as extreme laziness, or tardiness in coming down, with increasingly frequent calls, in a volley of
aaarkhs
from the bottom of the stairs. On meeting in the hall of a morning, we bow. She caws and I greet her. We bow again. She caws. I bow. She bows. I ask after her health. She caws. Eventually, we reach the kitchen.

Corvids belong to the order ‘passeriformes’ or ‘perching birds’, an order divided into two sub-orders, the tyranni (suboscines) and the passeri, or oscines, ‘true songbirds’, which comprise almost half of all bird species. Corvids are oscines, and though many people might question their inclusion on aesthetic grounds at least, that is where, by virtue of their evolution and taxonomy, they belong.

Only oscines, humans, whales, dolphins and some bats demonstrate vocal learning – the rest, anything else that utters sounds, does so because it is innate, not learned. Non-oscines such as doves and owls do not have to learn their songs; even when removed from other doves and owls, infants grow to make the sounds that membership of their particular species determines they should. Oscines on the other hand, like humans, have to be taught. Songbirds, parrots and hummingbirds learn their songs by listening to and imitating the songs of adult birds of their own species.

The songs of oscines are learned in infancy, most during the first two months or so of life, and although they may still learn later, their capacity to do so appears to be reduced. Studies have shown that if removed from their parents but taught song by a bird of their own species, they’ll still learn to sing, whilst those who are not taught at all will sing abnormally. As with humans and speech, birds have to be able to hear their own song in order to sing. Young birds will ‘practise’, making small, indiscernible sounds at first, ‘subsong’, during resting half-sleep, an almost silent trill in a faintly moving throat, sounds that will develop and enrich and grow to become ‘plastic song’, which finds expression in the full, complicated songs of the adult bird.

The sounds all birds make are determined by their anatomy, of both their brains and their mechanisms of song production. At the base of a songbird’s trachea, above its lungs, is that unique bird feature, the syrinx, by which sound is produced. There are many different syrinx structures, all complex, some super-complex, oscine syrinxes being more complex than those of sub-oscines. In most birds the syrinx divides into two cartilaginous rings, with two thin membranes – the tympaniform membranes – stretched between them, to enable the shape of the syrinx to be adjusted to create different sounds. On exhalation, the tympaniform membranes vibrate to produce sound, while the muscles of the syrinx alter the tension of the membrane to change pitch. In many birds, each side of the syrinx can function independently, allowing the development of intricate, layered song, sometimes two separate songs at the same time, in a
bewildering variety, the vocal near-miracles that surround us in every shrub and tree.

(In the interests of research, an unfortunate crow was recently anaesthetised by researchers at the University of Utah and had an angioscope, the ultra-fine fibre-optic tube used to examine blood vessels in humans, inserted into its syrinx, which was activated by pressing on its chest. The mechanism that produced the resulting
caw
was captured, usefully enough, on high-speed video. Unpleasant though it might have been for the crow, it could have been worse. In
Il Libro
dell’Arte
, the wonderfully informative fifteenth-century painter’s manual, Cennino d’Andrea Cennini provides instructions for making casts of people, animals, fish and birds. The latter three, he helpfully suggests, have to be dead ‘because they have neither the natural sense nor the rigidity to stand still and steady’.)

Birds have a set of brain nuclei and neural pathways, the ‘song system’ that controls both the learning and the production of song. The song system is made up of discrete brain areas – the High Vocal Centre or HVC, Area X and the Robust Nucleus of the Arcopallium, the RA. The song system is sexually dimorphic, larger in males, who sing better than females, the HVC of some male birds being eight times larger than that of females of the same species. In some birds the HVC and RA, subject to seasonal hormonal changes, are larger during the breeding season. Many parts of a bird’s brain develop during the period of their learning song. In some birds the left and right sides of the brain can work independently of each other to produce a diversity of sounds.

The discovery of the process of neurogenesis, the development of new brain cells in parts of the avian song system, has excited particular neurobiological interest. Studies of avian brain areas responsible for song learning and song production, their mechanisms and the effects of damage to them on a bird’s ability to learn or sing, appear to offer hope in the further understanding of similar structures and problems in humans.

Birdsong is a subject almost overwhelming in the range of its complexities and facts: numbers of birds, numbers of songs, each species with its varieties and variations, its responses, exchanges and dialogues, duets and mimicry, warnings and greetings, the messages we cannot yet understand. Birds sing, or make the sounds they do, for many of the same reasons that we use speech and song, to make ourselves known, to praise or warn or attract, for defence or for the expression of fear or feeling. The variations sung by individual birds are astonishing, as are the numbers of songs produced – the chaffinch may sing up to six songs, the nightingale two hundred, the brown thrasher two thousand. Hundreds of individual sounds may go together to form what we identify as one particular bird’s characteristic song. Context and geography affect what is sung, through subtle alterations of frequency, pitch and tone. Assorted sea-birds calling together create a mad amalgam of dissonant sounds; the puffin, between complaining ghost and chainsaw, the high, persistent squeak of the Arctic tern, the petrel’s rolling hiccup and the warbling choke of cormorants, the low resonant bassoon of the shag combine like an orchestra of maniacs equipped with instruments from a scrapyard.
Indeed, not all song is song. There are the clackings and tappings, the drummings and whistlings, the purposeful noises made by beaks and wings and feet.

Do birds enjoy their song? Does it only sound as if they sing, at least in part for the sharp, distinctive pleasures of exchanged speech, for the passionate, redemptive delight of raising their voices? The other evening, a spring evening of warm sunlight, the first in many weeks, I listened as Bardie and the blackbird in the ivy outside sang together, a douce duet, a cockatiel–blackbird fusion, a continent-spanning chorus of question and answer, phrase and response, prolonged and delightful, from which both parties, as it grew darker, seemed reluctant to withdraw.

On paper, birdsong can be represented visually by means of sonograms, mysterious and wonderful, voices trapped on paper, graphs of time and frequency in infinite, beautiful patterns of line and curve and shadow, the song of any bird rendered in smudges of ink, repeating and repeating.