Читать книгу Ireland Through Birds - Conor W. O'Brien - Страница 8

MERLIN

Dundalk

The chase is on. The tranquillity of the wetland is shattered as a cloud of starlings and finches bursts from the grass, and writhes in rapid undulation like a great airborne mollusc. Their tormentor, at first silhouetted against a pale winter sky, suddenly weaves after them, its form obscured as it twists and turns above the long grass. A boomerang made flesh, freed from the rigid trajectory of its wooden avatar, and able to realise true mastery of the aerial pursuit.

In this hunt, the outcome depends not just on the skill of the hunter but the mistake of the hunted. One false turn, out of sync with the swirling flock, or even a wingbeat or two off the pace, and it’s over. The predator inverts, throwing its talons forward to punish the deviant. In such a high-speed chase, impact can mean instant death – if the victim is lucky. Less fortunate prey are stunned but still alive, bound in the agonizing grasp of talons, swung forward so the hooked beak can finish it off with a nip to the neck. Then, it’s off to the plucking post.

The flock alights again. Calm resumes across the wetland after the brief but furious incursion. The songbirds continue their harvest of seeds and grubs among the grass and low bushes, mercifully spared by the falcon.

…

I love raptors. Though I like all birds, birds of prey have always had a special fascination for me. The power, the elegance of form, the eyesight on a level far eclipsing our own … it all made for an avian enigma, augmented by how elusive they so often proved.

And then there are the talons. As a boy who grew up on dinosaur books – and someone still enamoured with the ties between dinosaur and bird – I saw in the raptor’s talons the perfected descendent of the killing claws of their Cretaceous namesakes. Now, it isn’t the middle toe, with the switchblade raised, that does the knife work. In modern raptors it’s almost invariably the hallux, at the back of the foot, folding home to complete the clasp, that kills the prey.

Long ago, the raptors carved up predatory duties among themselves. Owls laid claim not to a certain prey but a certain time; with few exceptions they hunt from dusk till dawn, a time when few other birds can find purchase on food with eyes trained for the daylight. Eagles are the powerhouses of the family, the big-game hunters. Vultures are the undertakers, charged with recycling the corpses left behind in the wake of illness, predators and old age. This is no easy task, for carrion is always in hot demand and they must often soar huge distances to find it.

The hawks we know diverged along two broadly different paths some time ago: the accipters (think our sparrowhawk) are terrors of the forests, menacing songbirds as they weave between the trees on short, rounded wings; the buteos (think buzzard), bulky and barrel chested, soar in the open, typically targeting the rabbits and other small mammals that graze nervously in meadows around the world. Kites and harriers rival the buteos in size but are often more buoyant, preferring to take smaller morsels, even insects and earthworms.

And then there are the falcons, the avian spitfires. In their introductory blurb on the falco genus, field guides so often focus on the ‘tooth’, referring to the spike on the upper mandible. This serves as a sidearm to help dispatch prey.

But for me, having first flicked through guides to the birds of Ireland as a child, it’s always been the eyes: seemingly pure black, as if the pupil has consumed the rest of the surface to soak up every drop of light it can. In this respect, falcons are almost totally unlike any other birds of prey. And even on a moving bird at a distance, they can sometimes be seen clearly. Most often for me they’re encased in the head of the kestrel that haunts the banks of the river near my home, waiting in the wind for rodents to leave their ultraviolet calling cards, the drops of urine that will draw their reckoning to them. The black crown jewels of the kestrel can venture into a colour spectrum beyond that of human sight, and it is this that guides them through the grassy labyrinth.

We have three native falcons in Ireland. The peregrine is the king; at full dive, it’s the fastest animal on Earth, tearing down cliff faces and mountainsides with such velocity that it can decapitate its victim on impact. By far the most familiar is the kestrel. It’s perhaps our commonest raptor (though the sparrowhawk could also stake a claim). The kestrel thrives in the grassy verges that border our main roads. Here it hovers (the only falcon we have that does so) with consummate patience, waiting for its prey to betray its presence before descending in steps, readjusting coordinates for the final pounce.

Then there’s the merlin, the smallest of the three. Rather than relying on patience or a devastating dive, the merlin is a pursuit hunter, winning its meals through agility and perseverance. While the peregrine rains death on its victim from above, the merlin hunts lower to the ground, often forcing its victim skyward. Twisting and turning on frantic wingbeats, it’s as if the bird delights in exhausting and outmanoeuvring its prey. Where possible, the merlin will give itself the edge by ambushing its victim on the ground, sullying it with a standing start. Even when flying about in the open, the rapid, flicking flight style of the merlin evokes that of a thrush, allowing it to disguise itself in plain sight – until it is close enough to give chase.

Birds of prey are famously dimorphic; females are larger than males in a reversal of vertebrate norms. In the falcons this is particularly pronounced. The male is a third smaller than the female, leading to the name ‘tiercel’. Given this, gender roles play a key part in merlin life. The slate-grey tiercel, smaller and swifter than his mate, uses his speed to poach small passerines in flight. The bulkier female, with more punch to her killer blow, can tackle larger songbirds, up to the size of thrushes. Sometimes the pair will even work together to win a meal: one bird flushes the prey, the other takes it out. Between them, they provide a regular protein supply for young merlins each spring, reared in treetop eyries in mountain ranges across Ireland. At first the male does the bulk of the hunting, but once the chicks have matured enough for the female to vacate the nest, she chips in to fuel their rapid growth.

It is in its springtime demesne that the merlin resumes its rivalry with another inhabitant of our mountainsides: the skylark. Every breeding season, this rambunctious songbird can be heard blasting out a winding stream of notes from high in the air, wings beating frantically to keep it aloft.

Skylarks are among the merlin’s favourite prey in Ireland, second only to the meadow pipit. The male skylark’s song, as with that of almost all birds, is used to attract a mate and declare territory. But it also plays a vital role in the species’ relationship with the merlin. The fittest males can sing mid-air with the most vigour – and typically, it is these males who are spared the killing embrace of the merlin.

Silent males, or poor singers, are not so fortunate. Like the merlin, the skylark is an accomplished aerial acrobat. But only males with a powerful singing voice – a vocal expression of their flying prowess – can hope to outpace the merlin in an airborne dogfight. Less accomplished songsters stand a better chance if they simply drop to the floor and stay out of sight. Because of this, the airborne singing of a strong, healthy skylark is akin to the prancing of a svelte antelope on the savannah. It advertises fitness and virility, as alluring to a prospective mate as it is dissuasive to a hungry merlin. A predator’s energies are better spent in pursuit of a slower target. It’s just one way the merlin has helped prune the skylark population to peak fitness, and hone its mating rituals over many generations. Concomitantly, faster skylarks have undoubtedly left slower merlins to starve in their wake over the eons, leading to the refinement of the tenacious pursuit predator that torments their descendants today.

Treetop nesting does not come naturally to merlins in Ireland. Traditionally birds of uplands in spring, for generations merlins nested amongst heather, seeing off any avian interlopers with ruthless aggression. As afforestation has ravaged the uplands, they’ve increasingly taken to nesting in trees, commandeering disused corvid nests for their own ends.

Perversely, merlin chicks born in trees are often more likely to fledge than their counterparts on the ground, perhaps because there are fewer predators to threaten them high in the branches. But this dramatic change in the landscape hasn’t been entirely beneficial for our smallest raptor. The razor-sharp, pointed wings of the merlin are designed for pursuit in open terrain; this is not a bird of confined, wooded spaces, where the broad, rounded wings of the sparrowhawk come into their own. The loss of the heather has shrunk the available habitat in which breeding merlins feel most at home.

The merlin is not as cosmopolitan as our other falcons. Kestrels, predators of farmland and road verges, are easy cohabitants with humans. Among the peregrine’s favourite prey are pigeons – pigeons that thrive like rats in urban spaces. Because of this, peregrines have followed their ambitious human counterparts from the remote hillsides and clifftops to the cities in search of an easier life. They’ve taken to hunting amidst high-rises and quarries, and the crannies atop churches and cathedrals make ideal nesting spots.

In general, the merlin hasn’t transitioned as well to the world of man. The bulk of its small Irish breeding population remains confined to the shrinking pool of suitable upland habitat each spring. This makes it one of our more difficult birds of prey to find, and much cherished amongst birders.

Like its cousin the peregrine, the merlin was also hit hard by pesticide poisoning, building up through the eco-system to impact the predators at the top. In North America, where the merlin–peregrine dynamic also exists, this even led to a curious shift in merlin behaviour. When the peregrine went into decline, the merlin suddenly found itself the top falcon on the winter wetlands of Washington State. With no peregrines to challenge them, the merlins started hunting more in the open with a swagger becoming of an apex predator. However, when peregrine numbers rebounded, the merlins resumed the low-to-the-ground hunting more typical of their species. Perhaps this was to avoid the wrath of the peregrine – they both dined on the same prey, and a peregrine is certainly large enough to make a meal of a merlin.

Wetlands are oases for birdlife in winter. It is here that the merlins typically descend to after their upland bounty has run out and the weather starts to turn (though some males lag behind in the mountains to hold on to their cherished breeding territories). This is when the merlin becomes a menace along our coasts, often perching on logs and other flotsam to catch its breath or enjoy a kill after another frantic chase.

It is in the hopes of seeing one of these wintering hunters that I make my way to Dundalk, County Louth, home to one of the largest areas of exposed mudflats in the country. It’s exactly the kind of place that wintering merlins frequent.

…

The main street is desolate. Pubs, bookies and antique shops are locked up for Sunday. There are no signs of the Saturday night carnage as the road leads onto a bridge crossing the Castletown River. To my left, the vast banks are coated in grass stretching away into the countryside. To the right, the Castletown meanders restlessly towards Dundalk Bay.

The bay is one of Ireland’s largest natural harbours. It is this strategic advantage that has drawn envious invaders to Dundalk over the centuries. Ancient settlers were quick to establish themselves in this area, leaving a legacy of passage tombs in their wake. Later, the Normans, upon prosecuting their conquest of Ireland, made a point of settling in Dundalk, at the northern reaches of the Pale, facilitating as it did easy trade with Britain.

This corner of Ireland was also amongst the first to experience the wrath of the New Model Army – although Dundalk was spared the worst of the bloodletting. Hearing of the horrors that beset their compatriots in nearby Drogheda, the people of Dundalk surrendered to Cromwell without a fight. The peace that followed the ravages of the Irish Confederate Wars allowed the port to thrive, and industries like linen and brewing to flourish in the town. The resulting prosperity would manifest in Dundalk’s distinctly Victorian character, still discernible today in stately churches, cobbled streets and weathered shopfronts given new leases of life as boutiques and ethnic food outlets.

Crossing the bridge on a chilly February morning, it doesn’t take long for the first signs of birdlife to reveal themselves. Black-headed gulls bathe with vigour in the shallows, beating water over their backs with cupped wings. The mud pooled at the riverside serves as a jetty for lapwings, grounded by the stiff breeze. They turn their masked faces towards me in unison, streamlining themselves against the wind, two-pronged crests whipping like a helmet weathervane. Behind them, the detritus of the river – crisp packets, beer bottles, plastic wrappers – gathers amongst flattened reeds. Snipe shelter here in clusters, lending a golden-brown sheen to an otherwise drab, polluted scene. They seem content to conceal themselves amongst man-made squalor, oblivious as to how their colour is its only saving grace.

The riverside, though, is no place for a merlin, and so I start to follow the Castletown towards the sea. On the far bank, gulls of a myriad of whites and greys dot the shoreline. Those that brave the harsh wind swirling in from the coast hang in suspended animation, as if strung from the ceiling of a child’s bedroom. That same wind whips the river below them into a moiling swell. I can only imagine how cold it must be. At intervals, a cormorant surfaces, draped in beads dredged up from the depths, tiny pupils fixed in green eyes giving it a startled expression.

The path that traces the riverside overshadows a rocky shoreline, festooned with dank seaweed. Every few minutes, a redshank bursts from the shore with a panicked cry, only to be defeated by the wind and land just a few metres away. More at ease are the ruffs that also feed amongst the rocks. This can be a hard species to see in Ireland; Dundalk is one of the best spots for them. In summer, the males sport one of the most spectacular feathered appendages of any bird: the eponymous ruff, like a lion’s mane but more refined, forming a hat atop their head and curling around to complete a beard. This can vary from rufous to black or white, giving a selection of colours for the females to choose from at the communal leks where breeding males establish their credentials.

Sadly, wintering ruffs lose their fair-weather glad rags, attaining the more modest greys and browns typical of visiting waders, scalloped wings a souvenir of recent splendour. Robbed of their headgear, the males can look tragically plain, even potbellied, with their protruding midriff accentuated by the elongated neck and small head and bill. It’s as if they’ve purposefully flocked to a town once pregnant with Victorian vigour, in the hopes that some of this will rub off and restore the ruff that was the height of aristocratic fashion in days gone by. But even without their crowning glory, they can still strike a handsome figure in the morning light, periodically piercing through the clouds to lend them an ochre hue.

A few streets of terraced houses. A Gaelic football field sprinkled with oystercatchers, orange bills nestled beneath black wings. Rounding the bend, the mouth of the Castletown re-emerges before me. On the near side, the muddy bank rises steeply towards a wall. Across the river, skeletal vestiges of ruined wooden structures protrude at odd angles from the water. Each, to my eager mind, would make a perfect perch for a raptor, offering a commanding view of the wetland and the ducks and waders laid out in legions across its surface. But there’s no merlin in sight.

Not that Dundalk Bay is wanting for wildlife in their absence. The place is flowing with birds. Beyond the mudflats on the far bank, low reed beds, like a wheat field gone feral, stretch out into the distance. The Mourne Mountains are hazy on the horizon. Closer to, the café-au-lait brown of the mudflats is broken by a vast line of shimmering grey: knots, aligned in their thousands, every single one with their heads buried in their backs, as if in formation. Amidst their ranks one renegade stands out – bright red, a precocious romantic already in full breeding finery. A soldier of spring, surrounded by the grey phalanx of winter.

Fortunately, he’s not the only colour to be found on the riverside. Shelducks, with greens and oranges peeling into white, patrol the shoreline. More numerous are the teal, the males with their striking green-and-red helmets, filtering their way through the shallows. And at the heart of the river, a pair of red-breasted mergansers dive and surface in unison, like a submarine ballet. Lounging on the surface, pulsating with the waves, the male’s crest is battered around by the incessant wind.

I find so often with birdwatching it can be the stillness that stirs the life around you. It’s as if motion is one half of a totality, and your motionlessness forces the creatures in your shadow to move to restore the balance. If you stop to admire the glowing blooms of a gorse bush, the linnets within will erupt in a cacophony of chirps and white-bladed wings. Taking in the view from a seaside path, you’ll often send the curlews and godwits below scurrying for safety. If they’d just stood still you’d have been none the wiser to their presence.

It’s the same with birds of prey. When looking for raptors, unless they’re on territory, I often find your best hope is to let other birds do the hard work. These birds, with sharp eyes honed by instinct to react with revulsion to raptors, will usually be the first to spot the predator – and respond with venom. Buzzards, for instance, often have their presence betrayed by the cohort of irate corvids they draw into their orbit. Crows rarely shy away from challenging raptors – especially when they have numbers on their side.

Smaller passerines can’t do this. Usually they flock together, giving them the double advantage of more eyes to spot a predator, and more bodies to make it less likely you end up in the predator’s scope. When a raptor is spotted, instead of mounting an offensive, they take off in collective panic; a tornado of feathers intended to confuse their tormentor. This is usually the giveaway that a threat has been spotted. And it’s the smaller raptors, the falcons, the ones that take songbirds on the wing, which elicit the most potent response. Birds as big as a buzzard rarely bother with starlings or finches (and could almost never catch them even if they did). Instead, it’s the boomerang wings of the falcon, that consummate aerial killer, that strike them with the deepest fear. And so it is this response that I search for across the expanse of the mudflats.

Hope overtakes me whenever I see the redshanks, dunlins and shelducks on the opposite bank burst into flight. Periodically, amidst the probing and sifting of mud by bills long or flat, there’s an almighty commotion. Dunlins whirl with white bellies flashing. Shelducks lumber into the air in twos and threes. This is it, I keep thinking. The hunt is on.

But it’s a hollow hunt. There is no raptor to be seen as I scan the riverbank. Perhaps it’s a fox skulking amongst the reeds, a mink slithering out of the murk, or just a collective compulsion to seek a less-exposed section of mud on which to shelter from the breeze. Whatever’s disturbed the ducks and waders, it’s no raptor.

The long path tracing the river finally terminates at Soldier’s Point. It’s crowned with a haunting sculpture entwining a boat with a sepulchral human figure, as if in joint homage to Dundalk’s maritime tradition and also the past horrors visited on the people of this area. It recalls a time when not just airborne vagabonds made their way to Dundalk. Being a prominent port, during the Famine the town served as an exit point for thousands of desperate emigrants, searching for salvation overseas.

Below, the briars spread out past the last houses, a writhing mass of botanical carnage, crudely held back by slanting fences. I can make out no birds, much less raptors, amid the morass. The beating wind, with no features natural or man-made to impede it, makes it difficult for birds to make any headway. Most cling to the ground, hidden amongst the thorns. Beyond the briars, the mouth of the river is whipped into a swell. Winter still holds the bay in a merciless embrace, like talons, borne in of an eastern breeze, grasping at the exposed belly that is where Dundalk meets the sea.

But the battle of the seasons is a precarious one. By late morning, as I approach the spot where my sojourn began, the expanse of the Castletown River is bathed in sunlight. The breeze eases. If only for a moment, it feels like winter is in retreat, and has surrendered the town around me to the spring. In its wake, winter soldiers are left stranded on the muddy banks of the river: ruffs, in pairs, patrol the shallows, scalloped feathers unassuming, not yet succumbing to the aristocratic beauty they will soon assume. More stately are the godwits, long bills buried beneath the water’s surface, that sewing machine motion as they pry a steadfast worm from its burrow. And, among them, something special.

Amidst the redshanks dotted across the riverbank, I notice one, paler and thinner than the others, pirouetting in the water, like a dog chasing its tail. A darker stripe through the eye, and a bicoloured bill narrowing to a droop (think a drop of blood pooling at the end of a syringe) clinches the ID: a spotted redshank, a rare winter visitor, and another bird with a penchant for Dundalk and its surrounds. It’s a good find – some would say better than a merlin. Spinning about in the water on legs that seem almost too thin for its body, the bird pitches forwards mid-circuit, as if its head is suddenly too heavy to hold up. From the footpath I watch this ensemble of waders, the rare mingling with the common, none of them nervous about my presence. With birdwatching, you sometimes don’t always get what you want. But often, you get so much more.

My quarry has eluded me. But the search must go on. High-concept wildlife documentaries require months or years of toil, with untold near misses. Finding my merlin won’t be so arduous. On a wetland not so far flung, or a mountainside bog in spring, it’s waiting on its plucking post.

The sun creeping higher over Dundalk starts to warm my cheeks. Spring is on the march. Soon the ruffs and the godwits and the spotted redshanks will all be gone, an army of winter lodgers departing for the far north. But in their wake will come other visitors to fill the void.

A feast of spring and summer birding awaits.