Ever since being knee-high to a sparrow I have enjoyed a series of iconic summer sounds. These include the stridulation of grasshoppers; songs of soaring skylarks; the buzzing of bees at flowers; the gentle cooing of woodpigeons and the joyful screaming cries of swifts as they speed, wheel, swoop and vocalise from May to August. At my primary school my class master, an avid birdwatcher himself, devised a game whereby the whole class was instructed to run around whistling, arms outstretched, trying to avoid one another thus imitating the behaviour of the birds above. It was great fun and good exercise. I cherish the memory.

For the past thirty years swifts had nested in a large building nearby and the birds were constantly flying from dawn to dusk.

Then last summer the building was enshrouded in scaffolding and renovated and from what I can see the roof spaces were sealed, thus denying the birds entry.

As a result, only a maximum of four or five now cleave the skies on sickle-shaped wings and the skies above are often silent and empty.

For those three decades I enjoyed the time just before dusk when dozens of local swifts would form up into a tight vortex, always in the same place and with cries becoming fainter and fainter, gradually spiral up as they reached for the heavens to roost on the wing.

I miss that time. From my observations it appears that this summer is seeing a sharp drop in the swift population everywhere. No doubt sealing of roof spaces is a major factor for this sad state of affairs.