New season is off to a flying start
The clans are gathering although not the ones wearing tartan! Instead, these are feathered clans, which even now perhaps are beginning to feel the influence of the wanderlust that impels them to put their lives on the line and undertake perilous journeys of thousands of miles.
Swallows certainly seem to be getting ready for that amazing migratory flight. They are either lining themselves up on the overhead wires like so many crotchets and quavers, carefully preening in preparation for that exodus, or zooming low over the fields, hoovering up countless flying insects in order to ensure their fuel tanks are full.
Of course, the feasting is vital, for in essence these intrepid travellers are literally fuelling up for the marathon they are about to undertake with an incredible journey of 6000 miles ahead of them. This year’s crop of youngsters will inevitably and instinctively be drawn into that mass exodus, yet they can have little understanding of just what lies before them. Some of them, the later broods, may be no more than a few weeks old so they virtually begin their lives with a 6000-mile aerial trek!
Right across the Northern Hemisphere millions of birds are similarly readying themselves for such adventures as the need to translocate to warmer climes impels them to move, en masse, southwards. Most of these travelling masses are birds that depend upon insects and as summer wanes and autumn begins its slow advance, the availability of this essential source of food is curtailed. Thus, to survive, they must follow the instinct that has driven so many generations of birds to follow this course of action since the end of the last Great Ice Age.
This movement southwards, in a sense began many weeks ago as no more than a trickle at first. As soon as their dastardly deeds had been done, adult cuckoos for instance, departed these shores as early as July, leaving the poor unfortunate foster parents – many species may fall under their spell - to get on with the soul-destroying job of rearing cuckoo off-spring. Their devotion to the rearing of this single chick is absolute, despite apparently being utterly unaware that their own progeny have been thrown overboard by their single, monstrous chick!
Gone too are the swifts. In midAugust, village rooftops suddenly fell silent as the ‘devil screamers’ upped sticks and headed rapidly south. Furthermore, this year’s youngsters now face the prospect of remaining airborne, not just for the forthcoming winter months, but probably for the next two years at the least. They will return here next May as immature birds, but they will not mate next year or indeed, the year after, remaining on the wing throughout next summer, the following winter and the following summer too! They will feed and drink on the wing and snatch brief naps on the wing. These are what might be regarded as super flyers and their migratory journey to the southern mainland of Africa is, as anyone who has watched swifts might guess, rapid!
And, the sighting of a single osprey the other day confirmed that the bulk of these fish hawks too are on their way to West Africa. This year’s youngsters were fewer in number I fear, simply because fish, forced by the heat of summer to swim deeper, were consequently harder to catch. Having been so carefully nurtured by dedicated parents, those that did survive the heat, found themselves abandoned when suddenly their parents departed for their wintering grounds. Thus, they will quickly have to learn to rely upon in-built instinct and without any guidance whatsoever, find their own way to the Dark Continent alone. Staying alive as a young migrant osprey, can clearly be extraordinarily challenging!
At least the passage of ospreys is relatively leisurely, although it is vital that those travelling youngsters have honed their partly instinctive, partly learned fishing skills sufficiently well for them to be able to sustain themselves en route. At least the routes they will blindly follow will provide them with plenty of fishing opportunities. The key to their survival and their ultimate arrival in West Africa, is utterly dependant upon whether they are fully up for the task and able to catch enough fish!
Migrating swallows take their time too although more experienced, senior birds, having made the journey before are a little more direct than the younger birds. Swallows may congregate in substantial roosts at various locations en route, often in reed beds. While the young birds have in-built navigational skills at their disposal, their well-being and security is doubtless enhanced by the coming together of so many compatriots.
The existence of those innate navigational skills is manifested by the time-honoured routes they take, travelling from Scotland, through England and across Western France and Eastern Spain. The most demanding part of the route comes as they fly across the Western Sahara. Although swallows sometimes come together in large flocks during migration, most travel in relatively small groups, in tens rather than hundreds or thousands, not closely packed but reasonably well spread in order to allow room for them to feed. Swallows, of course, feed entirely on the wing. Flying the Sahara is quite an ordeal and of all the many migrating birds that perish during this leg of the journey, the main death-toll is indeed among swallows.
This is perhaps where the real benefit of the frenzied feeding currently being undertaken will stand them in good stead, providing that they maintain the extra weight during most of their journey. Swallows travel at relatively low altitudes in order to keep feeding as they travel. Therefore, winds are a major factor albeit that wind speeds are generally reduced at lower levels. Head winds are not quite as big a hazard as you might think, for such winds are easier to negotiate.
Africa is the winter home for so many of our insect eating birds. Swallows from Europe, it is thought, may number anywhere between 100 and 300 million as they pile mainly into South Africa. This year’s bitter springtime easterly winds probably did for a fair number of these, surely our most popular summer birds. In some ways, this insect ridden, hot summer may have helped them compensate and there seem to be encouragingly high numbers of them currently preparing themselves and gathering for their epic journeys.
I wish them all a safe journey. It is now, according to the Met Office, autumn although my interpretation of autumn remains stubbornly at the solstice later this month. As the swallows depart during these next few weeks, in a sense they will, however, take our summer away with them. If our hope may be for an ‘Indian summer’, let’s also hope they bring another good summer when they return next spring!