feats of endurance and ability. Imagine their surprise when the pilots of an Air India passenger jet found themselves flying alongside a large skein of bar-headed geese at thirty-two thousand feet, an altitude required every year as the geese cross the highest Himalayan peaks.
Radio transmitters have revolutionised bird research. Very recently, an electronic tracking device weighing less than a paperclip uncovered what is now thought to be one of the world’s greatest bird migrations. It revealed that a red-necked phalarope, a tiny wader the size of a wagtail, migrated thousands of miles west across the Atlantic to the Pacific Ocean, a journey never recorded for any other European breeding bird.
Dave Okill, of the Shetland Ringing Group, fitted individual geo-locators to ten phalaropes nesting on the Shetland island of Fetlar. When a bird returned to Fetlar in the spring, Dave was astonished to discover that it had made an epic 16,000-mile round trip during its annual migration – across the Atlantic, south down the eastern seaboard of the US, across the Caribbean and Mexico, ending up off the coast of Peru, taking the same route back. Prior to this, many experts had assumed that Scottish breeding phalaropes joined the Scandinavian population at their wintering grounds, thought to be in the Arabian Sea.
My conservation colleague Roy Dennis has hugely increased our knowledge of osprey, marsh harrier and golden eagle movements by attaching transmitters to young birds leaving the nest. The British Trust for Ornithology has done the same by attaching solar-powered radio tags to English cuckoos in an attempt to discover the route and precisely where our diminishing British cuckoo population spends the winter. The results have been illuminating and, for us, deeply disappointing. Aigas Field Centre sponsored one bird named Kasper; he made it to the Congo Basin for the winter, but perished on the way back in the spring – just our luck. Of the first five birds tagged in 2011, only two made it back to Britain.
Sophisticated modern radar can also accurately track the movement of small passerine migrants. We now know that most small birds migrate at below five thousand feet, the most popular altitude being two to three thousand feet, whereas flocks of waders choose to travel much higher, at twenty thousand feet. We can also measure speed of flight very accurately. Warblers, finches and other small birds commonly cover thirty to fifty miles a night with daytime stopovers to rest and feed, whereas swifts, swallows and house and sand martins regularly cover up to two hundred miles a day, preferring to roost at night and fly by day so that they can feed on flying insects as they go.
Raptors, such as ospreys and harriers, tend to move much more slowly, travelling by day and using thermals to spiral upwards so that they can glide for long distances before rising and repeating the process all over again. The exception to this rule may be falcons. Only twenty-four hours after it was ringed in Paris, a young peregrine falcon was gunned down on Malta, some thirteen hundred miles south, an average of fifty-four m.p.h. without stopping.
* * *
For me, here and now, migration means geese and swans, waders thronging the mudflats of the Firth and woodcock slinking into the woods. Our small summer migrants all vanished south long ago, but the onset of winter brings the Arctic species down to our more favourable climes. I lie awake at night, listening out for the haunting music of whooper swans bugling through the moonlight. Then, with the first frosts and an east wind, woodcock suddenly arrive in droves from Scandinavia and Russia, escaping the snow and ice.
It is a gamble. If, as seems likely, birds are triggered into migrating by the length of daylight, they must also assess the weather, choosing suitable conditions and the right wind to travel. Two years ago the Scandinavian woodcock got their timing horribly wrong. They arrived in the Highlands, which were gripped by an unseasonably severe November frost. There had been a light snowfall immediately followed by –18ºC, even on the coast.
The land fell silent. The Beauly River froze over. The loch became gleaming glass in the low-angled sun, and huddles of disconsolate mallard sat about preening on the edge of the rigid marsh. There was nothing else to do. The ground and its snow crust, even in the sheltered woods, was as rigid as concrete. Woodcock are woodland waders with long probing bills for winkling invertebrates out of the litter layers of damp forest soils. Unable to break through, they starved. My good friend and colleague Peter Tilbrook, former Nature Conservancy Council and Scottish Natural Heritage director, who lives on the east coast at Cromarty, doesn’t miss much. He phoned to tell me that migrant woodcock, which had just arrived, were starving in his wooded garden. They were so weak that he could pick them up.
In the Aigas garden there is a small patch of wet woodland where a spring rises. I have never known it dry and I have never seen it freeze solid, although in very hard winters the open pool has grown a skin of thin ice. The spring water seeps away into the soil beneath the spreading branches of 120-year-old, close-planted western red cedars, whose closed evergreen canopy provides a resin-scented arbour like a secret den – a place where my children loved to hide when they were small. Following a hunch after Peter’s phone call, I went to have a look.
There they were. Three woodcock stood together on the damp soil, their large black eyes in sculpted soot- and cinnamon-barred heads stared blankly at me. I backed off, reluctant to stress them any more than the weather already had. The ground was dotted with the pockmarks of their hungry probings. I prayed they were finding something to sustain them. They stayed there a week, until the anticyclone drifted back towards Norway and a mild west wind flooded in to free us up.
How did they find that lonely wet patch, I wondered, the only one in a world of ice? What tricky avian sensibility had led them to that secret place? Could they scent the damp soil over the heady essence of cedar resin? Had they been there before in hard times? Did one wise old bird tell the others? So many questions, so many riddles. Such a cloud of witnesses.
4
And Then There Were Rooks
Above the dark and drooping world
Let the empty skies disclose
Your dear, delightful crows.
‘Crows’, Arthur Rimbaud
Crow realized God loved him –
Otherwise, he would have dropped dead.
So that was proved.
Crow reclined, marvelling, on his heart-beat.
‘Crow’s Theology’, Ted Hughes
I can’t claim any prescience; neither am I given much to old wives’ tales or pithy country aphorisms. An abundant fungal flora or a heavy crop of rowan berries doesn’t seem to me to mean anything more than a bumper year for fruiting fungi and rowan trees. When the greylags and pink-footed geese arrive earlier than expected, harrowing the September skies with their treble-pitched clamour, all that it tells me is that the season in their Arctic breeding grounds – Greenland, Iceland, Lapland – is turning, and that their migratory instincts have fired a little earlier than in some other years.
Not so Old Malkie, famous round here for his doom-laden predictions, when I bumped into him at the Beauly petrol station. ‘That’ll be the snow on the way any day now,’ he gloomed, waving his walking stick to the puckering late-October clouds and shaking his platinum curls. (To my intense chagrin, three days later there was a sugaring of snow on the three-thousand-foot pyramidal crest of Beinn a’ Bha’ach Ard [hill of the high byre], which impales our cloud-laden horizon to the west.)
Yet despite all the head-shaking and dark muttering by the nay-sayers and would-be country sages in our glen, it did not seem to me to follow that blizzards are imminent, that we are in for a harsher winter than usual or that the end of the world is nigh. But I am moved by the wholly unexpected.
