Corvus (26 page)

 
high and difficult places

In the morning Chris and I drive out of town, round Loch Linnhe to Loch Eil. We leave the car at the head of Glean Sron a’ Chreagain. Most of the walking is on tussocky grass and heather, rising, steeply sometimes, over streams undercutting turf, spilling and seeping into dark peat mud, our boots squelching blackly, loudly, wetly, gravity’s dark pull tugging at our soles.

A cuckoo begins to sing not long after we set off, accompanying us, seeming to be first to our left and then to our right. Whether it’s the same cuckoo or many, I don’t know, but the sound is with us for a long time, abandoning us only as we climb higher, when it goes silent. Then it’s the breathless, high silence of hills, all sound sucked into the heather, all but our own breath, the sounds of our feet. It’s too early in the year and too cool for midges, the ever-nagging bane, the ever-biting presence that drives some to fury and others to madness, and many to both. It could be, as Lochaber often is, wrapped into cloud and rain but today it’s not. Pale butterflies flicker ahead of us among the first flowers. Tiny frogs dance at the edges of burns. Tadpoles swarm like dark spermatozoa under a microscope at the margins of standing pools. The occasional lizard darts from the approach of our boots.

The hill is Stob Coire a’ Chearcaill, a ‘Corbett’, a mountain of 2,500–3,000 feet. The walk is more long than difficult but we don’t hurry. It’s quiet too. We see no one else all day. Not many people, Chris says, come this way.

Today is Laitha Buidhe Bealtain, the bright day of Beltane, the Gaelic day of celebration when Beltane bannocks, oatcakes, were once
baked and scattered in an act of propitiation to the forces of nature – fox, wolf, raven, eagle – to ask them to spare sheep, cattle and chickens their malign attentions. On this day ancient Celts purified themselves with fires of juniper, celebrated the end of hibernation, the new beginning of the fecundity of warmth and light. Beacons were lit to celebrate the end of winter. Hearth fires were extinguished before being ritually relit, and cattle were led between two fires in an act of purification. The icy reign of the Cailleach Bheur, the Queen of Winter, was ended, the power of Bride, the Queen of Spring, renewed.

Bride, daughter of Morrigh and Dagda, of the ancient fairy race of Ireland, has her origins in pre-Christian, Celtic mythology, her identity merging with the first-century St Brigit of Kildare, miracle worker, midwife, healer. She has two birds associated with her name, the raven and the oystercatcher, the first because her feast day falls at the time of their nesting. A poem from the Uists is reproduced in
Carmina Gadelica
, a compendium of Gaelic hymns, stories and poems collected in the latter decades of the nineteenth century:

Up here, it’s easy to imagine the fragility of existence, the need to propitiate and ask and hope. There are fewer ravens now in Scotland, and no wolves. The last wolf was killed in the middle of the eighteenth
century, possibly to the detriment of the raven population. The state of mutual co-operation between ravens and wolves is well established. Ravens both follow hunting wolves and lead wolves to carcasses, a process of benefit for wolves and even more so for ravens because, being unable to tear open animal skin themselves in order to feed, ravens need an animal that can initiate the feeding. (There has been discussion for years among wolf enthusiasts about the desirability of reintroducing wolves to Scotland. I like the thought. Apparently, they’d keep down a burgeoning red-deer population. They’d eat sheep too, but the rest of us would be safe since hill walkers don’t seem to be a feature of their diet.)

A deer stands bathing in the water of a small lochan. It watches us for a while, steps out before we approach too near and lopes away. Loch Sheil’s beyond us, scattering white light to the horizon.

We stop for a rest and as we sit an object, a black triangle, flies at speed down the length of Loch Linnhe below us, low, sharp, black. When we lived here, I used to rage as earlier models of this black triangle of death roared down the loch, too near to my windows and my children. I used to phone complaints to their base, sounding like the whining pacifist they must have thought I was, but I’d lived in a warring country and didn’t want my children raised within the sights or sounds of war. They have to practise, the weary voice on the end of the phone always told me. Practise for what? And here they are, still practising, decades on, taking with them on their flight down the loch my naïve belief of long ago that international political progress is ineluctable, that things improve and justice prevails.

It’s after we’ve been walking for five hours or so that Chris points suddenly to something I can’t see at first, even through binoculars. It’s a raven, high on the hill above, watching us, tramontane intruders into this silent land. There’s no sound, then a single
orrkh
!
In a quick, black flicker, it flies off. We walk on and hear the nest before we see it. From behind a buttress of rock, low sounds, muttering, croaking, reach us on the wind. The nest is in a cave gouged from a wall of rock at right-angles to where we stand and not easily seen. Below us the descent to the valley is steep, precipitous, not quite vertical. I’m secured by the rope Chris has brought. Chris isn’t, which is quite reasonable. He is easy and brave with heights while I am a tremulous wimp. We have to edge down the grass and stones carefully, singly, to a ledge where it’s possible – just – to sit. I edge along the narrow shelf of grass and lean out. Through binoculars, I find the nest. Below, the adult ravens stream round the space below us, two thin, crossing black lines.

Inside the cave, in semi-darkness, we can just see three or perhaps four grey shapes shift and move. In the five or six weeks since hatching, they’ll have grown from pink, blind nestlings to feathered creatures weighing three or four pounds. (How much food-finding must that take? How much flying and looking and thrusting down three or four constantly waiting throats?) The young call, their voices low and asking, not the usual high voices of infant birds. A fold, like cloth, dangles a corner from the edge of rock. It wasn’t there, Chris says, when he was here last. It looks like a piece of deer skin, furred, like a rug thrown over the edge. Wind moves through the rocks with
a sound of blown grass. Stacks of cracked rock and layered grass are piled like an ancient desert city.

The site of the nest is majestic, the pinnacle of all nest sites, inaccessible, impossible to reach except by flight. It looks as if it has been used for a long time. Hanging streamers of grass trail far down the rock-face under the cave, whitened, stiffened. Splashes and runnels of white, thickly coated, decorate the rock, above and below. Above the cave there’s a shape marked out in white. We discuss what shape it is. A sporran, Chris suggests. I think it’s a shield. But it’s both. It’s a sporran-shaped shield, a raven coat of arms inscribed above the cleft of rock, ancestral, armorial. An escutcheon. Edging down the slope, we take turns to watch and in turn are watched. The parents fly and land and fly again, keeping us always in their sight. Inside the nest there’s movement, a beating of wings, a dialogue of croaking. The young look as if they’re preparing to fly, flapping their wings in practice. We sit for a while, take turns to edge down to watch. The infants are large enough to be alone for extended periods. Soon they’ll fly. They’ll stay with their parents during the summer, until they’ve learned what they need to know, most importantly to find their own food. We don’t want to disturb them for too long. I don’t want to turn and leave them but we don’t want to keep their parents from them.

We walk higher, to a large, carefully constructed cairn. There are raven pellets balanced on rocks, grey-white, dry and ashy, constituted from greyish feathers, from pale slivers of bone, matted, felted fur, earth, raven spit. We pick them up and put them in our rucksacks with pieces of quartzite from the hill.

Driving home the next day, I think incessantly about the birds, wondering if they’ve flown yet and how, remembering the fragility of the lives of wild birds, the few that survive their first year. As I drive, the sun is beginning to break apart towards the east, clouds massing in a grey-blue sky. These days will be the last prolonged sun we have for months.

As I unlock the front door, Chicken runs from her patch of sunlight in the sitting room, calling to welcome me. I look into the doo’cot and replace a couple of new-laid eggs with cold ones. I check on the blackbirds in the ivy. Wood pigeons and collared doves are feeding at the bird-table. I put the pellets and quartzite on the mantelpiece. Over the next weeks, the pellets dry out, the grey feathers become white, and I wonder whose they were. The rain starts and doesn’t stop, the beginning of another summer.

O
n a July afternoon, I drive to the farm shop, a few miles from Aberdeen. Just before the turning to the farm, a black bird appears in the air in front of me, in slow, considered flight. It stops in the air, not hovering, not moving. Amazingly, it seems for this moment utterly still, suspended in the air, like a photograph, as if the world has stopped, as if we have become stone, or an image on a page. It is a rook. Slowly, assuredly, it floats into a turn, to descend towards something on the road in front of the car, holding its wings out, touches delicately down. There are no cars behind me so I sit while it redeems its unseen prize from the tarmac and carries it to safety on the grass verge. I have never seen this before, this stillness, this ability to hold the air, to freeze the frame. A rook. I am impressed.

It’s universally acknowledged, one of those things we no longer even need to think about, that humans, or most of them, nurture the
desire to fly, that everyone, sane or otherwise, must at some moment have envied the power of flight. No one, surely, can watch a bird step easily from the edge of a roof into that pure moment, to expand into the air over the sorry world below, without envy, without the shadow of the thought that it’s not fair, that we have (albeit without much effort on our part) evolved to the high state in which we believe ourselves to be but still cannot, and will never, fly. Most of us accept with grudging equanimity that birds can and we can’t and we’re grateful (or not) for the little we can achieve, flapping a strapped-on, bound-to-fail accessory as we’re pulled by gravity towards the bottom of the sea, or gazing down on cloud and sea and city from ill-ventilated metal tubes stuffed with people and trolleys of food and screens busy with entertainment to take our minds from the boredom, paradoxically, of flight.

There are those who can’t accept it, as there have always been, those who will try anything to raise themselves beyond the restricting bounds of the earth. So far, every human attempt, mythological or not, to emulate the flight of birds has been risible, a history of crazy daring, of failing and falling, of everything complicated, risky, doomed, the true antithesis of the delicacy, lightness, the unmediated facility of bird flight, from Icarus’s melting wings to the jet pack, all so very far from that one ethereal, lifting moment we will never achieve. Leonardo da Vinci famously said, ‘For once you have tasted flight you will walk the earth with your eyes turned skywards, for there you have been and there you will long to return,’ a sentiment that presupposes he knew from experience – which he didn’t, because, works of genius though his drawings and inventions were, all evidence suggests
that they didn’t fly, or, if they did, not sufficiently well for him to be able to opine in quite such elevated tone on the pleasures of the sky.

There is a truism, ascribed to Churchill, that says that dogs look up to you and cats look down on you, while pigs look at you as equals. He didn’t mention birds. Birds, I’ve learned, look at you from a measured distance. Birds, some at least, know that they know more than you.
We
– their look says –
we, apart from everything else, apart from our
grievously underestimated intelligence, our so-
far-
unstudied tendency
towards passion, our unexpected tempers, the ferociousness of our determination
to please ourselves, we
, their calm, superior look says, can fly. In their look is the certain knowledge that they have uncovered the sharpest point of human envy, that one certain thing they can do that we cannot.

They make it look so simple. One summer morning as I walk up the lane, I watch a crow flying above the stone walls of the gardens. Last night’s storm has calmed but it’s still blustery. The crow turns sideways to the wind, seems to lie on the air that carries him forward. He turns, dips into a current, allows himself to be swept upwards, his wings held wide, black serrated feathers clear against the sky. His movements seem all pleasure, the sublime ease of his progress making me forget what flight is, what it entails, the long, slow evolutionary processes it has taken to create this melding of wing, feather and air, the aerodynamic complexities, the balances of force and lift, thrust and drag, the historic triumph this morning journey represents of creature over gravity.

Wings, most evolutionary biologists seem to agree, are exaptations,
physical features that, having evolved for one purpose, evolved further for a different purpose entirely. To fly, you need a strong skeleton, rigid but light and hollow-boned, a keeled sternum, a furcula, joints that fold and lock, large, powerful flight muscles (pectoralis and supracoracoideus), muscles that pass through a hole in the bone, and the foramen triosseum, where scapula, humerus and coracoid meet to form a pulley system that allows the wings to lift. As it flies, the bird’s furcula bends outwards to each side on the downstroke of the wings, recoiling powerfully on the upstroke. The bones of the wing are like human arm bones, but with fused wrist bones and only three ‘fingers’. When Louis J. Halle writes of wings in
The Appreciation of Birds
, ‘Man has never invented anything at once so strong and so delicate, anything so sensitive in its adjustment to the continuously varying conditions it has to meet,’ it’s impossible, after a moment’s consideration, a quick mental scan of every human invention one can recall at the time, to disagree.

Thinking of the evolution of wings makes me see, as nothing else does, how much birds are part of the earth, part of the air. They are as we have ceased to be: indivisible from the circumstances of their evolution, evolved for climate and terrain; changes in human habitation over time, migration and the loosening of ties with places of origin mean that our skin and eyes, the shapes of our bodies, tell us little about who we are and more of who we were. Wings, in all their variations, their fusion of form and function, are what they have to be, suited minutely to their purpose and their place, adapted in every way to the demands of flight and life. The nature and requirements of
flight determine precisely the shape of the wing, that ever-altering, moving, shifting structure of fragility and strength. Wings in flight are never still; in hovering they hold, wait, balance, learn the air.

Wings are curved, airfoils, convex on top, concave below, tapering towards the end, bisecting the air, which in flight flows over the top surface of the wing more quickly than over the lower, increasing dynamic pressure, reducing static pressure, while on the lower surface of the wing both dynamic and static pressure remain the same. The difference in static pressure between upper and lower surfaces of the wing creates ‘lift’, the force that allows the bird to fly. Each type and shape of wing deals in a different way with the forces of the air, with drag and lift, thrust and gravity, with the topography of earth, each meets its relevant climatic circumstance, from the lightest breeze to tempest, from the demands of stillness, the invisible, fluid transfigurations of thermal change. There is powered flight – flapping flight (the complexities of which almost defy explanation) – and non-powered flight, gliding and soaring. Gliding is flying without flapping the wings; soaring is flight for which the bird uses energy from the movements of the air to fly. In dynamic soaring, a bird will use air streams of differing speeds and velocity to gain height. Large sea-birds will fly between waves, using the power of the air to carry them upwards. Thermal soaring uses the rising heat of air thermals, while slope soaring uses the warm air deflected from hills or buildings. Flight is more than a mode of traversing distance. Flight forms understanding with the air, senses wind, temperature, height.

Dynamic soaring is undertaken with high-aspect-ratio wings (the
ratio of length to breadth), the wings of albatross, gannet, gull: narrow, smooth-edged, unslotted, elongated along their proximal edge, wings to give slow lift, to carry these birds vast distances for prolonged periods over open ocean, borne by the necessary wind. Corvid wings allow manoeuvrability for birds whose terrain is among trees, in gardens, city landscapes, those who have to turn, to negotiate, to flee, as do the wings of small passerines, of thrushes, blackbirds, sparrows, of grouse too, elliptical, low-aspect-ratio wings. The high-lift wings of eagles, storks, owls and hawks have slotted feathers, gaps between the primaries which increase lift to give them the wide flight they require for static soaring, allowing them more easily to carry prey. Falcons, vertiginous vertical divers, like members of the families Apodidae and Hirundinidae, the swifts and swallows and martins, the screeching speed-demons of summer towns, have specialised high-speed wings, unslotted, high-aspect ratio, as the wings of terns, ducks and sandpipers. For the swifts and swallows, they’re designed not only for speed but also for feeding on the wing, for long migration, the unimaginable journeys during which they traverse the world in answer to the unexplained, instinctual compulsion within. And high-speed the wings are. Peregrine falcons can dive at 180 miles an hour (there are reports of planes diving at speed being passed on the way by falcons), although precise speeds are difficult to measure, being dependent on the strength of the wind. The speed range of birds is astonishing, from a leisurely 15–18 mph for sparrows to 217 mph for some swifts. Their wingbeats too vary with purpose and with size: seventy beats per second for hummingbirds, one per second for vultures.

The wings of owls are shaped to give silence to their noctivagant flight, their feathers fimbriate – fringed on the margins of the outer vanes of the first two or three primary feathers – so that contact between the air and the leading edge of the wing is muffled. Fine velvety pile on the dorsal surfaces of the inner vanes of all wing feathers and some tail feathers achieves the same, allows the owl his soundless nocturnal hunting. (I always think of owls when I read the metaphysical poet Henry Vaughan’s poem ‘The Night’, where he writes of ‘God’s silent searching flight’.) It is feathers that allow flight, infinitely specialised in shape, form and colour, adapted minutely for each purpose and circumstance.

In 1861, the perfect impression of a feather was found indented into the limestone of Solnhofen, an asymmetric, secondary wing feather, at the time detached from its owner, archaeopteryx, who was found shortly after. The significance of the find was in that it provided evidence that feathers existed in creatures dating from the Mesozoic era.

It was once thought that feathers evolved from scales, but it is believed now that, whilst they share origins, feathers evolved differently, from the placodes – embryonic epithelial cells – which may develop into scales or feathers. The finding of dinosaur fossils such as sinosauropteryx showed that some had early forerunners of feathers, simple hair-like structures, ‘dino-fuzz’. From these findings it has been possible to trace the stages of feather evolution from dino-fuzz – which may have provided insulation, waterproofing or camouflage – to the fully developed feather with its central rachis, its interlocking barbs and barbules: the feathers that give birds flight.

Light though they are, only 5 to 10 per cent of the bird’s total weight, they’re still two to three times heavier than the skeleton of the bird that carries them, this coat of asymmetrical wing feathers, feathers of flight, primaries and secondaries, the lesser coverts, which first meet the air, the main coverts in their rows, the retrices and remiges of wing and tail. Complex in structure, in colour, in form (used by the proponents of intelligent design, those creationists ‘lite’, as examples of entities, like eyes, too complex to have been produced by the process of evolution), they are composed of keratin, formed around a central shaft (the rachis), each vane made up of interlocking barbs and barbules, a system of hooks and catches that allows the feather to form a uniform surface to move through air.

Each feather has its place, the adaptation of size and shape determined by its purpose. A bird’s contour feathers, held in place by a special set of muscles, insulate, provide form, colour and camouflage; carefully arranged and aligned, they keep the bird dry, protect it against wind, allow it to fly. Down feathers, which underly the stronger outer feathers, are soft, their barbs and barbules loose to trap air, which make them the most effective insulating material in the natural world. There are also semiplumes, somewhere between contour and down feathers, whose purpose is to maintain the form of contour feathers; and filoplumes, which are straight, more like hairs than feathers, their purpose still disputed – they may play a role in assisting the bird to detect the direction of air-currents. The largest of the contour feathers are the remiges of the wing and retrices of the tail, the former attached to the wing bones, the latter by ligaments to the pygostyle.
The feathers of the outer wing are long, narrow on the leading edge, shaped to aid flight, slotted to reduce air turbulence, whilst those of the inner wing are shorter and more symmetrical. Tail feathers are used for steering and for balance, and for the often magnificent displays by which male birds attract and display.