Sunlight paints patterns on the curtains, leaving shadowy leaf shapes. Early traffic grumbles; great tits pipe. Then, above the murmurings of the starting day comes a shrill stream of sound like a fine line scratched in glass with a metal nib.
It is a “scream” of swifts, streaking down the street with exuberant shrieks; like children on a toboggan. In the quiet of the early morning it sounds as if they are right in-between the Bath Stone buildings, riding the winds blowing down the hill, then wheeling up and back to the top to do it again.
But “scream” does not have the right connotations: as Gilbert White, the great 18th century naturalist, remarked in The Natural History of Selborne, the “one harsh screaming note” of the swift most often occurs in “the most lovely summer weather”.
How often have you heard that cry and looked up, shading your eyes against the glare of a bright sky, only to see distant flecks in the blue like commas? Who has not yearned to fly up there, living on the wind, breaking free of the bonds of earth, “touching the face of God”?
It seems inconceivable that the swift can fly so high and so fast; and it ascends yet higher at dusk, rising up to 10,000 feet, even then refusing to succumb to the pull of the ground and shutting down only half its brain so it can sleep on the wing. It remains always aware of danger while asleep and can correct for wind shift, keeping its long wings outstretched to glide more efficiently with fewer flaps than while fully awake.
During the daytime the swift is a Red Arrow. Last year, a Common Swift took the record for the fastest bird – 47mph in horizontal flight, whereas the Peregrine Falcon uses gravity to dive at 186mph.
It lives almost exclusively on the wing, even mating in flight, something Gilbert White recorded for perhaps the first time. The only time a swift lands is for nesting in buildings, and then only clings on to vertical surfaces with its claws – indeed, its Latin name, Apus apus, means “without a foot”, since it is barely able to walk at all.
According to the British Trust for Ornithology, which tracks migrating birds, a young swift may fly nearly 300,000 miles nonstop between fledging and building its own nest the following summer. That’s more than two million miles in a lifetime, or 100 times around the earth.
The swift used to be called the Devil Bird because of its cry and its habit of nesting in old buildings, and even though we are more in tune with conservation today, numbers have declined by a third in Britain in recent years, says the RSPB’s John Day, because of a lack of nooks and crannies in modern buildings, as well as falling numbers of their insect food, thanks to pesticides.
Eve Tigwell of the BTO says there are three really useful things that people can do to help swifts. “Firstly, if there are existing gaps in their roof, don’t block them up, especially if swifts are already nesting there or are seen in the area. Secondly, if a roof is replaced, or with newly built houses, make sure that swift boxes are included in the building specification. Thirdly, if there are swifts in the area, put up some nest boxes. All these are particularly important where people see screaming parties of swifts.”
Now it’s August and our skies are becoming quieter – most swifts have left Britain to fly down through France and Spain to south of the Sahara where they will spend the winter before returning next April to the same nests they left this year.
We will miss them. The voices of blackbird and herring gull evoke their own special feelings; but when you hear the high, free keen of the swift, you know that summer is finally here.