33) Common Swift & White-throated Needletail

Apus apus & Hirundapus caudacutus

Turn on your TV.  Find, if you can, a programme filmed in Europe in summer.  Wait until there’s a scene shot outside, then listen to the background noise.  Before long you’ll hear a distinctive long, high-pitched shriek, or more likely a series of them: that’s the sound of a group of Common Swifts flying overhead.

The calling of Common Swifts is an inescapable part of summer in Europe.  It’s a kind of delirious swoop of noise which is an almost impossibly perfect description in sound of the experience of watching a group of Swifts cutting and swerving through the air.  In a world without humans Common Swifts would nest in forests or in caves, but as it is they’ve taken naturally to nesting in towns and cities, and so they must be one of the most observed birds in Europe – and yet there remains about them an innate and uncontainable wildness which marks them out from other city-dwelling birds: there’s a sense of exhilaration in their very being which makes the idea of their ever becoming fully urbanised seem preposterous.  Of course the fact that they’re seasonal arrivals in Europe, swooping across the continent to escape from the African summer, only marks them all the more with a sense of freedom, regardless of how much they may be slaves to their migratory instincts.  They appear suddenly in Europe in the middle of each year, gradually making their way north all the way to Scandinavia and the UK; by winter they’ve flown back south again, chasing the sun like so many Costa del Sol tourists.

Such migration is scarcely an unusual phenomenon in the bird world, but if ever there was a group of birds which seem naturally given to such journeys, it’s the Swifts.  The Common Swift is but one of around eighty species in the family Apodidae, and “swift” is an apt yet scarcely adequate name for the group.  If the name “fly” wasn’t already taken it would be a perfect name for the Apodidae: for Swifts are flight incarnate.

Consider their form: not large, but large of wing and more wing than body.  Those wings are long and anchor-shaped as a pair, and affixed to a body which is shaped like a torpedo; Swifts move through the air as fluidly as a fish moves through water, and at enormous velocity: speeds of up to 111 kilometres an hour have been recorded for the Common Swift.  No wonder they shriek!  The call of a Swift pushing the limits of its aerial capability could be equally joy or terror.

Swifts are no mere straight-line flyers, either.  They’re stunt pilots: banking and climbing, diving and swooping with astonishing dexterity as they manoeuvre through townscapes and pursue swarming insects.  Sometimes they can be seen flying high in the sky, tiny dots passing beneath the clouds; at other times they’ll appear out of nowhere and fly just above head-height.  To watch a flock of Swifts from the vantage of a hillside, in particular, is an exhilarating experience: they’ll come sweeping down from above, hugging the outline of the ground yet marvellously untethered to it, darting all around the watcher with delirious indifference.

What you’re unlikely to see a Swift doing is perching.  Common Swifts only come to earth in order to nest and, sometimes, to sleep, and if a Swift ever finds itself on the ground its feet and legs are so diminished that it is almost helpless, unable to walk or hop.  A life devoted so absolutely to one mode of locomotion clearly has its drawbacks, then: even Albatrosses (Diomedeidae), the family which perhaps come more readily to mind when we think of the great flyers of the bird kingdom, can make their way with relative ease on the land.  Not Swifts, though: Swifts are perhaps the most specialised of all birds.

Which makes it all the more peculiar that the White-throated Needletail should be so named.  The Needletail is the eastern equivalent of the Common Swift: every southern summer it migrates down through Asia and into Australia, its arrival in the south-east of the continent coinciding almost perfectly with the new year.  It’s larger than the Common Swift, with a wingspan of around fifty centimetres, but its size is deceptive: its short body and stubby tail can make it appear as small as the Swallows (Hirundinidae) with which Swifts are so easily confused, and it’s not until you hear the soft rattle of wings as a Needletail flies right over your head that you realise just how large it is.

The name, Needletail, refers to the shafts of the tail feathers, which protrude beyond the ends of the feather’s filaments.  These spines serve to anchor the bird on the tree branches on which it roosts.  The degree to which the White-throated Needletail employs this tool, though, is uncertain: a relatively small bird which flies at such great speed that it can cover enormous distances in a single day is understandably hard to monitor, and much of the Needletail’s behaviour is unknown.  It’s believed that the bird may, at least sometimes, sleep in flight; likewise, White-throated Needletails are believed to mate in mid-air.  I often think that the naming of birds somewhat misses the point: the White-faced Heron (Egretta novaehollandiae) could more properly be called the Grey Heron; the abiding impression of a Red-rumped Parrot (Psephotus haematonotus) is not the colour of the feathers at the base of the male’s tail which gives the species its name, but the vivid emerald green colour of almost all of the remainder of the bird’s feathers.  So it is that the White-throated Needletail is named for an anatomical feature which enables terrestrial roosting, an activity which, if witnessed in isolation, would give an entirely misleading impression of the animal.

It’s unlikely that anybody not in the habit of regularly handling and inspecting birds at close quarters will ever notice the particularities of a White-throated Needletail’s tail feathers, though.  The bird is too fast, and its tail too small; and besides, who, upon seeing a White-throated Needletail – or any other species of Swift, for that matter – would stop to look at the tail?  Or at the head, or even the wings?  Swifts are not birds which invite the casual observer to engage close inspection of bodily details; rather, they’re birds which demand a stunned appreciation of the animal in its elemental entirety.  They’re animals whose appearance – so suddenly present, so suddenly gone – is vivid in its completeness.  There are millions of species of animal on the planet, and Swifts, to those inclined to watch them, are probably the closest thing that any group in that entire multitude comes to pure sensation.

Common Swift image sourced from http://en.wikipedia.org / White-throated Needletail image sourced from http://www.birdingintaiwan.org/