By John Knox
The migration season is upon us again. ‘Tis the “season of mists and mellow fruitfulness….. and gathering swallows twitter in the skies.” It never ceases to amaze me that birds with tiny brains and such delicate bodies can out-fly us, out-navigate us, out-survive us, we who have the whole powers of human ingenuity and civilisation behind us.
The twittering swallows are leaving for South Africa, travelling 200 miles a day, at speeds up to 35mph. The gannets on the Bass Rock will be leaving shortly to spend the winter soaring over the Bay of Biscay. 50,000 geese will be arriving on Islay on an overnight flight from Greenland.
The grand Lady of the Loch of Lowes in Perthshire – the oldest breeding osprey we have ever known – has gone to her winter feeding grounds in West Africa for the 22nd time. Her latest offspring, “Blue 44” left on Saturday, heading down the East Coast main railway line. Another young osprey, Alba from Loch Garten, completed the same 3,000 journey in just two weeks. We know this because he called in on his mobile phone – otherwise known as an electronic tag.
Through such tagging devices, we now know more about the astonishing network of bird flypaths which covers the globe. A modest little woodcock has been tagged flying 4,400 miles from the leafy woods of Britain to the wilderness of central Russia. The arctic tern is the champion migrator. These slight, elegant birds breed in the Arctic summer but fly to their feeding grounds in the Antarctic to take advantage of its summer, a round trip each year of 44,000 miles.
There are many theories to explain how migrating birds navigate. Some follow coastlines, or mountain ranges or rivers or railway lines. Some follow the sun or the stars. Others follow the scent of vegetation. Some can detect the Earth’s magnetic field through tiny traces of iron in their beaks or in the retinas of their eyes.
Man has noticed this phenomenon for quite some time and been amazed and puzzled by it. Migrating birds are mentioned several times in the Bible. Aristotle tried to figure out what was going on. Many people believed that swallows go to the moon in the winter time. Others believed birds hibernated in secret places. As recently as 1878, the American ornithologist Elliott Coues in his Birds of the Colorado Valley could not discount the theory that some birds hibernated deep under mountain lakes.
Not all birds migrate of course, only 1800 species out of the total of 10,000 do so. And some species are undecided whether they are travellers or not. The female chaffinches of Scandinavia, for instance, migrate while the males stay at home. British starlings stay with us for the whole year but Danish starlings cross the North Sea to spend the winter here. There can be “moots” of up to a million birds all flocking together, swirling in one of nature’s most spectacular displays of individual yet communal activity. There is no leader but each bird is influenced by the others.
Nor are birds the only migrators – think of the whales or turtles or salmon or wildebeests. Perhaps even in humans, there is an urge to spend the winter somewhere warmer. Unfortunately, we need so much infrastructure to get there we are prevented from going (except for short trips to Spain).
But what intrigues me is this idea that migration is at once an individual activity and a communal one. Some birds travel alone, like the osprey, but end up in the same place as their fellows. Some travel together, like the geese from Greenland – taking that 20 per cent energy advantage in flying in formation. But none are led.
President Putin forgot this political lesson when he set out the other day to lead the Siberian cranes on their annual migration to somewhere in central Asia. Sitting precariously in his micro-lite, the ex-KGB agent, dressed in white to resemble the leading crane, flapped his way southwards only to be followed by one young and inexperienced bird. On the second attempt, five followed him but three turned back after just a few minutes.
It was not a great parable on political leadership. And perhaps the example of migrating birds is something we can all learn from, particularly nowadays when humans are becoming less biddable and more individualistic. We tend to swarm around computer messages rather than charismatic leaders. We believe more in the wisdom of the crowd rather than the wisdom of our leaders. And yet, miraculously, things get done…the Arab Spring, the stock-market crash, the craze for new products, the making of celebrities.
There is a lot to think about as we stand and stare at the starlings swirling in their self-choreographed displays or the swallows gathering in the autumn skies.
– John Knox is a former BBC journalist who now works part-time at the Scottish Wildlife Trust.