Читать книгу Curlew Moon - Mary Colwell - Страница 9

The rain barely stopped falling throughout the winter that saw a wet 2015 turn into a soaking 2016. That December was the warmest and wettest ever recorded for the UK. By early January, large swathes of northern England were underwater. Thousands of people were soaked in misery, made worse by the filibustering of politicians. Further south and east, Norfolk was, thankfully, not so badly affected, but it was still drizzly and the ground sodden. This area is famous for its water. Once a giant wetland, it was drained in the seventeenth century to turn large swathes of it into more productive farmland. Now, ramrod rows of poplar and Leylandii puncture the horizon, and deep, straight dykes define the edges of large fields. They seem to stretch as far as the eye can see. Much of the land is below sea level, in some places by nearly three metres. It can be disconcerting to contemplate that the low wall along the coast seems to be all that stops the North Sea piling in on top of you.

The north Norfolk coast is separated from southern Lincolnshire by The Wash, over 15 well-defined square miles of shallow sea and tidal mudflat. Four rivers – the Whitham, the Welland, the Nene and the Great Ouse – flow into the North Sea here, depositing tonnes of sediment. When the tide is out this vast expanse of worm-filled, shellfish-rich mud forms one of the most important feeding areas for waterbirds in Europe. In winter, it is filled with avian life from all over the continent – 350,000 birds at any one time, and as many as 9,000 curlews.

As soon as I arrive in Norfolk I head for one small section of The Wash, the RSPB nature reserve in Snettisham, on the coast. The whole day has been mild and damp, everything about it redolent of wet, musty sacks. By mid-afternoon, the light is already losing its sharpness, slipping into that unsettling, crepuscular zone between thin winter light and cold darkness. In mid-winter this comes so early in the day it feels like theft.

Through binoculars, shapes reveal themselves to be a ‘herd’ of around thirty curlews. Herd is one of the collective nouns, and is not a bad description, as winter flocks generally move together and take flight as a group. The other collective is a near homograph: a curfew of curlews, possibly relating to their gathering at dusk.

Like sewing machines stitching the sky to the Earth with invisible threads, the curlews prod the ground and generally move in the same direction. They form a fragile alliance. Though focused on finding food, their nervousness is palpable. Perhaps being watched stirs some ancestral memory of being legal quarry in England before 1981, when they were regularly shot on their wintering grounds. Birdwatchers say that they are noticeably more tense in areas where they were once hunted, and Norfolk is one such place. Some call softly, a whistling sound that floats over the damp air, soothing to the ear and a balm for the soul.

My small camera is balanced on a fence post to keep it steady at maximum zoom. The picture is boring, the birds are too far away, but the sound alone fills the screen. But as I press the ON button, right on cue, the throaty rumble of a microlight edges into the soundscape and rapidly becomes a roar. Within seconds it drowns out the music of the field. The giant petrol-powered set of wings takes an age to move along. If only the creators of the combustion engine could have made it sound like a wind harp or grand piano, maybe even a xylophone. Anything would be preferable to this grating, intrusive drone that fills the sky for what seems like hours.

In any case, the moment is lost. The curlews take flight, piping as they make their way towards the sea. And perhaps the microlight isn’t entirely to blame; it is just as likely the birds can feel the shifting tide in every cell of their bodies and register the failing light as a signal to move on to a safer place for the night. I pack up and follow them.

Mud and ankle-deep puddles form the narrow path to the shingle ridge that overlooks the vast expanse of shimmering tidal flats. It offers up a strange and beautiful sight. Channels of water meander across the exposed mud, silvery sinews on a dark surface, at times taking on the sheen of mother of pearl. There seems no end to the mud; it stretches on and on towards the darkening horizon, rippled and ruffled by the water, strangely enticing and mysterious. Even the thousands of birds here are dwarfed by the vastness of the estuary. The air is filled with bird calls and a caustic, rich smell. The curlews are out there somewhere, a part of this mighty throng, big and small.

Bulky shelduck patrol the surface of the mud like avian minesweepers, their distinctive upturned bills swishing to and fro, scooping up tiny molluscs. Pink-footed geese stream in from feeding in fields: an airborne, honking choir. Neurotic redshanks strut and fuss, then take fright at the slightest disturbance, sailing into the air, emitting their high-pitched wails. The ‘Sentinel of the Marshes’ they are called, the first to warn of danger; red-legged bird versions of Lance Corporal Jack Jones in Dad’s Army – ‘Don’t panic!’

The real star of The Wash winter show is the knot. Thousands of small brown and white waders seem to be held together by magnets. They rise as one, twisting and spiralling through the sky, like a creature in agony. The display confounds predators and mesmerises humans.

The sea creeps closer, pushing the birds towards the shore. They bunch together like commuters on a constantly dwindling platform. On days when the tide is very high, they can run out of space completely and tens of thousands take to the air and stream inland. You can find yourself standing beneath an aerial river of birds. It is one of the greatest wildlife spectacles that Britain has to offer. But today there is only a middling tide, and the birds stay on the seaward side of the wall.

Just a handful of us birdwatchers are dotted along the shore, each alone with our own thoughts, bathed in evening light and surround sound of calling waterfowl. I am imagining how different this will all seem in six months’ time, at the end of May. I will arrive on this eastern coast footsore and tired after six weeks on the road. There will be greenery and leafy trees, warm air and the hum of insects. The sun still high in the sky. There will also be far fewer birds. All being well, curlews should still be on their breeding grounds and guarding their growing families. If they manage to hatch young they will be kept busy until late summer. If not, if they fail to find a suitable nesting site, or if predators eat their eggs and chicks, they will already be gathering into small flocks, preparing for winter once more. The pattern of previous years doesn’t bode well. For most curlews in large parts of Britain and Ireland, far too many will, yet again, gain the depressing title of ‘failed breeders’ and arrive back on the coast way ahead of time. They will have lost the chance to produce young once more. The world is an increasingly uncertain place for them, as it is for many other birds.

All over the Earth the great pendulum of bird life swings to and fro in time to the beat of the seasons. Some migrants are well studied, but others are only just revealing their secrets as different kinds of tracking devices are developed and become smaller, lighter and more reliable. Hopefully, we will learn more about curlews in the future. It is amazing how little we know about their lives, particularly considering they were once so numerous and widespread. The everyday rarely gets the attention it deserves, until, that is, it becomes increasingly hard to find.

Organic farmer, naturalist and former wildlife camerawoman, Rebecca Hosking, described to me on Facebook her experience of catching a glimpse of winter curlew in Devon:

The north winds blew a pair of curlew to the farm this morning. Their unmistakable calls rooted me to the spot, as I watched them spiral downward to feed in one of the lower meadows. To me, their cry is the essence of wildness, both haunting and beguiling. I was astonished at the level of emotion those bubbling trills invoked. Pure joy and excitement, for this was the first time I’ve ever heard them at Modbury. Yet that joy soon turned to sorrow and lament, knowing how drastic their decline has been. My knee-jerk reaction was to run and find Dad so he too could hear. As we stood in the garden listening, the pair lifted back to the sky, calling their plaintive, lonely ‘cour-leees’ as they circled overhead. I looked across at Dad to see his reaction; his eyes were beginning to well, ‘I haven’t heard that bird in this valley in over 40 years,’ he said. We watched them slowly reel their way towards the coast, until they flew out of sight.

A fifth of Europe’s curlews visit the coasts and estuaries of the UK and Ireland in the winter, a number that is steadily declining. It is an awesome responsibility to hold the fate of these world travellers in our hands. Although most of the birds are unstudied, there are some hotspots for research, and The Wash Wader Ringing Group has been busy fitting identification rings onto the legs of curlews for decades. It has amassed some interesting results. Most of The Wash curlews breed in Scandinavia, France and Germany; only 25 per cent are British birds that stay all year round. Some visitors travel a long way. One curlew ringed in The Wash in September 2000 was shot in Russia the following May, over 2,000 miles away. It was fifteen years old. Surprisingly, this is only middle-aged. A bird caught in Lincolnshire in 2015 was twenty-nine, nearly matching the record for longevity which goes to one found dead in the Wirral in 2011 at the grand old age of thirty-two.

Thankfully, more projects are getting under way to understand the lives of these wonderful birds. In the weeks leading up to my walk I wanted to find out more about winter curlews, and so in early February I made my way to the northeast coast of Scotland, to the Moray Firth, where I had been told interesting things were happening.

I arrive to bright sunshine and a clear blue sky. A period of glorious winter weather is gracing eastern Scotland. After a few hours of searching, Bob Swann and I find curlews roosting on Bunchrew Bay, near Inverness, on the Beauly Firth. Bob is a retired teacher, wiry and strong, passionate about nature and with an encyclopaedic knowledge about sea birds in particular. He is a legend in the world of Scottish bird ringing, and along with others in the Highland Ringing Group, has contributed immeasurably to our understanding of bird life. I couldn’t be in better company.

The Moray Firth is another important wintering site for many species of wading birds. Numbers in excess of 36,000 spend the winter in and around its many inlets and lochs. Dunlin, redshank, golden plover, lapwing, ringed plover, sanderling, purple sandpiper and knot join curlew here, many coming over from Scandinavia. The Highland Ringing Group has been monitoring numbers and fitting identification rings onto the legs of curlews for many years. The results show that all of the curlews wintering in the Moray Firth are either Scottish or Scandinavian birds. Overall, there are more males than females (58 per cent male to 42 per cent female), and some specific sites are predominantly male. Very few juveniles have been ringed, only 4 per cent, indicating that either they roost elsewhere or, far more worryingly, there are very few around to ring. Over the years birds have either been spotted or re-caught in the same places. The Scottish curlews – and it seems to be the same everywhere – are very much creatures of habit, returning year on year to the same places.

A simple identification ring fitted onto a bird’s leg is one way of getting information about an individual, but as technology advances we are able to resolve mysteries about their lives – which was impossible before this digital, data-streaming age. For example, as tracking technology gets smaller and lighter, we can now vicariously tag along on the journeys they make throughout the year. On 31 March 2009 Bob was part of a team that caught a female curlew at Bunchrew Bay and fixed a satellite transmitter to feathers on her back. It is rather cumbersome-looking with a long antenna attached to a small black box (a couple of centimetres squared), but it is light and only in place for a few months since it falls off when the feathers moult in the autumn. As the bird was caught at the end of March, the suspicion was that this was a Scandinavian female. We know that curlews breeding in northern Europe remain on their Scottish wintering grounds longer than local birds, waiting for milder weather to melt the frozen northern lands. By the middle of March, British birds are already on the hills, preparing to nest.

Once she set off, the transmitter sent back data every few days over the spring and summer. Technology now allowed the Highland Ringing Group to track one bird’s annual migration through data streamed to a computer screen.

The female left Scotland in mid-April and flew over the middle of Norway, passing through a gap in the mountains. After a few days’ rest in Sweden, on the Gulf of Bothnia, the data then showed a flight across to Finland. For fifty-three days she was stationary, long enough to nest and raise young. The return trip to Scotland took a different route via the southern tip of Norway, before crossing over the North Sea to arrive north of Aberdeen by 1 July. Eventually, by 5 July, the female arrived back where she started, on the Beauly Firth.1 Thus we have a circular migration, not a straight line back and forth, showing that curlews depend on vast areas to support them through the year and all these places are important for their survival. It’s interesting that the satellite transmitter confirmed that this curlew was away from Scotland for no more than three months of the year, highlighting that the birds we call ‘northern European’ are actually spending three-quarters of their time in the UK. Protecting wintering areas around our shores is therefore just as important as safeguarding their nesting sites.

The project provided an insight into the year of just one curlew, so plans have been drawn up to expand the database. The next phase, which I was here to see, involved catching many more curlews and fixing smaller, cheaper devices, called geolocators, to the rings on their legs. These marvels of technology collect data and store it onboard the locator, rather than constantly streaming it back to a computer. Geolocators record light levels so that sunrise and sunset can be worked out and the birds’ positions identified. Cheap and less cumbersome, for sure, but in order to retrieve the data the same birds have to be recaptured later in the year and the geolocator removed, although, as curlews are so site-faithful, that is not such a tall order as it sounds.

The first step involves catching lots of curlews. If you are not au fait with cannon netting, and just happen to come across it in action, you might think something heinous is going on. It involves laying explosives, creeping about in the dark, setting off very loud bangs and trapping frightened birds under nets, but it is all for a good cause.

The proposed curlew catch on Bunchrew Bay requires preparation. A long net, with two firing cannons attached to the ends, is buried in the beach where the curlews are known to roost overnight. The detonator is hidden in bushes and attached to the cannons by long cables. When the birds are standing peacefully, the explosives will be detonated and the net will shoot into the air and over their heads, trapping them underneath. They will then be put into holding pens and the geolocators attached.

After a few hours of lugging and digging, everything is set for the next morning.

I leave the guesthouse before dawn; a hard frost covers cars and pavements. Scotland glistens under the streetlights as I drive to meet Bob and his ringing colleagues by the beach. Most of the group, like Bob, are retired, field-fit, passionate bird lovers. The birds are exactly where we hoped they would be, so if all goes well, we’ll have a large catch. Bob, with walky-talky and binoculars, creeps to the far side of the beach and into the bush with the detonator. The rest of us move quietly to the other side to hide in a small patch of woodland. As Bob sends updates about the birds’ position, we sort out who can run the fastest. Once the cannons have been fired, speed will be essential. The quickest sprinters will leave the bags and equipment with the slower ones, then race ahead to retrieve the birds from under the net. The birds would be panicking, so getting them to the safety of the holding pens is vital. This is where I feel I can contribute. Having run a few half-marathons, and being a keen gym-goer and jogger, I confidently put myself forward to go with the advance party. After what seems like an age of whispering and walky-talky instructions, Bob counts down. Five, four, three, two, one – FIRE! An enormous bang shatters the early morning air, followed immediately by alarm-calling birds. RUN! I race off at full speed. My fellow sprinters streak ahead so fast Mo Farah would struggle to keep up. I arrive only just ahead of the ‘slower’ group, who have had to transport all the bags. But there is no time to soothe my bruised ego …

Retrieving the trapped birds is fast and efficient. This well-oiled machine of seasoned bird ringers has been through this routine many times. The birds settle quickly. In all, over a hundred have been caught. The list reads: one wigeon, four teal, one oystercatcher, eight curlew, two dunlin, seventy-four redshank, thirteen black-headed and three common gulls. All are weighed, aged, measured, ringed and released. The curlews also have their geolocators fitted, and, for the first time, I get to hold a curlew in my hands.

Not surprisingly for wild creatures, some species of bird will peck and struggle when held. The more pointed the talons, or sharp the bill, the greater the caution needed. They glare fiercely at their captor with rage or terror. Some are notoriously vicious, like the sea-cliff-dwelling razorbills (the clue is in the name). Curlews, however, don’t do histrionics. Despite having a bill that could take your eye out, they simply sink into your hands and have a look around. They are gentle captives and exude a Buddha-like calm. It is as though being cradled in our hands takes away the pressure for survival for a short while. I am sure this is far from the truth, but the impression they give is one of serenity, not panic.

It is a special, life-giving moment to be so close to birds that I have loved and admired for so long. As I cradle them one at a time, I feel their hearts beat fast but steady. Under their soft feathers, they are warm and surprisingly fragile. We look each other in the eye and I fancy there is a connection. I stop short of giving each one a soft kiss on the head – that is way too infra dig in front of the Highland Ringing Group.

By mid-morning each bird has been released into the bright sunshine and the cold, fresh air. As they fly away I wish them well and hope they come back in the autumn so that the geolocators can be retrieved and reveal their secrets. The curlews call out their characteristic ‘curlee’ as they wheel down the beach. I worry that the exploding net and human handling might have traumatised them, but, reassuringly, after some indignant shaking, each one starts feeding. By the time we have packed up, the beach is once again calm, as though nothing has happened. Months of waiting now lie ahead before the birds return in the autumn and the cannon nets are laid out again.

Cannon netting might seem dramatic but it is a useful tool for birds like curlews that are hard to catch in any other way; and its use is spreading. Two weeks later, at the end of February, I find myself once again stumbling through woodland in semi-darkness. This time it was to find out more about a new inland cannon netting project in the Yorkshire Dales.

It is late afternoon and I am following (or trying to follow) a silent, stealthy, ex-army officer who barely cracks a twig as he moves through the shadows with ease. His training with the Irish Guards, and a Military Cross for bravery in Iraq, are obviously useful for birding. He floats over the ground and uses the tree trunks as cover. I, on the other hand, fall over every root, get snared on brambles and catch my rucksack on most overhead branches. I can barely see a thing.

Tom Orde-Powlett is in his late thirties, and retired from the army to help run the family business, which happens to involve the upkeep of a medieval castle and a 6000-acre grouse moor. For six centuries his ancestors have owned and managed Bolton Castle Estate. He also has four small children, so life is busy. Tom, though, is fired with a passion for birds and is involved in all kinds of ringing and monitoring projects around the area. I will return to the grouse moor later in the year, but this visit is to see the large number of curlews that winter in the fields along the River Ure, which tumbles through the valley below the castle. Most curlews in the UK winter on the coast, but some come inland to places like this in quite large numbers. A few hundred birds are known to spend the winter in Wensleydale, making the most of the rough, wet fields below the hills. This is a stunningly beautiful part of England. On this wintry day, the elongated, smooth moors are dusted with snow and produce stark, white wedges against a pale blue sky. England is a crowded country, but the Yorkshire Dales feel wide open and sparse. There is space to breathe.

The light is fading fast. The fourteenth-century fortress that once hosted the fugitive Mary Queen of Scots looms above us, dark and brooding. Tom leads the way through the small shelterbelt of conifers to the edge of the field where a hundred or so curlews often roost overnight. There is no cannon netting tonight; this is a reconnaissance trip to check their location. We settle on a log, telescopes ready, and chat quietly. Little is known about these Yorkshire birds. Do they breed on local hills or have they come from far away? Are they a mixture of sexes and ages? One theory suggests curlews that winter inland may be predominantly males, as their shorter bills are more suited to reaching food in wet, soft soil. The females, with their longer bills, are more adept at extracting food from sandy, muddy shores and rocky coasts. No one knows for sure, and so Tom, with the help of local nature groups, is trying to find out. In January, over forty birds had been caught using cannon nets and each bird was given a unique set of coloured bands for identification. While the rings were being fitted the birds were also weighed and measured. The majority were found to be male, supporting the theory that the sexes may separate to some extent in winter. More cannon netting is being planned, but in the meantime it is important to keep a lookout for birds already ringed. Once spring arrives it might be possible to see where they nest, or to hope for reported sightings if they are breeding elsewhere.

There is something tinglingly magical about woodlands, even small patches like this, in the half-light of a winter evening. They are steadfast and full of expectation; there is a sense of a change of shift from day to night, from the known, visible world to the realm of covert creatures that move in shadows. After the wet, warm winter the rotting leaves and rich soil give off a primeval, earthy smell. As a cold wind buffets the valley, the trees provide a sense of calm. I feel I am wrapped in a woody blanket.

A lacework of bare hedges defines the large field ahead. The ground is sodden and an area of standing water in the middle reflects the grey and pink sky. After a short time, the calls of curlews drift in from the distance. They sail overhead, landing by the water, touching down like fighter planes. Their long, pointed wings tilt to kill the lift and slow momentum. Their heads and necks stretch out and downwards, and their long legs, with pointed toes, dangle below. They delicately touch the earth. At first just a few arrive, then they are joined by more and more. They whistle and call to each other and begin to feed in a herd of about eighty birds, moving first one way, then turning and walking back. A brown hare appears in the background, sniffs the cold wind and lopes away. Occasionally, one curlew rises into the air and sings a succession of ascending notes before floating back to the group. They are trying out their mating displays, and seem restless. Something is stirring in the February air; the approaching spring seems to be awakening their instincts.

Despite the cold, short days, winter is coming to an end. The world is on the cusp of change. Birdsong becomes louder and more musical, more earnest. Buds bulge and green shoots have more vigour. The curlews feel it. Their migration to their summer grounds is about to begin. It will be a staged journey, not a direct flight. Very soon this group in Wensleydale will split up and head to the same breeding grounds they have always gone to. These are birds of routine and faithfulness. They will stop for a few days in the same fields, in fact the same spot in the same fields, calling and displaying, searching each other out, always heading closer to their final nesting place.

Most of the Wensleydale curlews might not have far to go. It is likely they spread out over the surrounding moors and upland farms. Others, though, could travel hundreds of miles. Previous studies suggest some birds may head to Teesdale before heading out to Scandinavia. This new ringing project will help fill in some of the gaps, and I left Tom with plans to return when the birds are nesting and the valleys and moors are burgeoning with life. I drove back to Bristol with a mind full of wintery new moon birds singing in a grey, flooded field.

As the seasons shift, so too do the winds around the Earth and the currents in the sea. Movements in air and water bring a fresh energy to a winter-weary world. That energy can bring new life and new generations – but it can also be lethal. Gales, fog, heavy rain and storms can hit just when the birds are on the wing.

On an unusually foggy, cold night, on 9 March 1911, there was ‘a tremendous night of Curlew cries over Dublin’.2 Thousands of birds of different species – including curlews, thrushes, starlings, robins and skylarks – were ‘streaming over the south and east coasts of Ireland, heading north. They were exhausted and disorientated.’ One man near Waterford recorded, ‘The whole bird creation was astir and the people of the town were kept awake by the shriek of the Curlew, Duck and Snipe hovering over the town.’ A ship’s captain reported ‘millions of birds’ alighting on his ship. ‘Amongst them was a number of curlews.’ Lighthouse keepers told of birds crying and wheeling around the lanterns in the dead of night. A certain Mr Fanning was awoken from his sleep and wrote, ‘Curlew were heard calling continuously over the town of Lismore … the air was full of them. The nights were dark and foggy, and the birds kept hovering over towns where gas-lamps were lighted.’ And in Carlow, ‘the sky was almost obscured by vast numbers of Curlew and Starling … The streets were practically littered in the morning with the bodies of dead birds.’ Another report describes a man out walking at midnight and finding curlews, ‘walking up and down the flat bank at the side of the river, screaming piteously.’ It must have been a tragic and disturbing sight.

Returning to their breeding grounds from wintering in southern Europe, these poor creatures seem to have been caught out by extreme and unusual weather. Having been held back for longer than normal by intense cold across the continent, the temperature across France suddenly rose, accompanied by a change in wind direction. The birds took their chance and left en masse, but what the birds didn’t know was that Britain and Ireland were still in the grip of a deep freeze. As warm continental air hit the cold air over the North Sea, a bank of fog extended 30 miles from the coast and conditions were made worse by a waning moon, providing very little light. Cold, exhausted and disorientated, the birds made for any light source they could find, hence their landing on ships and lighthouses. Thousands died.

Bad weather during migration is not uncommon, but extreme events like this are, thankfully, rare. However, migration is always dangerous. Hunting and lack of food at stop-over sites make a hazardous journey far worse. Yet, still, the urge to fly to far away lands full of insects and good nesting areas is strong; it is an instinct that is impossible to resist.

The shift from winter to early spring was making me restless, too. The date set for the start of my long walk, 21 April, was just a few weeks away. It was time to plan my own, hopefully far less perilous, journey to Ireland.