Sarah Gibson - Swifts and Us

Swifts flying around Gaudis La Pedrera building in Barcelona.

Laurent Godel

It is commonly believed that if you find a grounded swift, you should pick it up and throw it in the air, preferably from an upstairs window. This is one of those scraps of information that you absorb without thinking and which, like many other such unquestioned beliefs, is actually wrong. Yet this is what I did and it did not help at all.

I had advertised an evening walk each week of the summer around a small town in Shropshire, to find where swifts were nesting. For thousands of years we have shared the buildings we live in with assorted wildlife. Nooks and crannies within the weathered masonry of our homes have sheltered many different living things; the walls between us and the outside world are porous. It did not happen intentionally but was a consequence of the building materials available. Today we can so easily make them airtight that we run the risk of losing our wild companions. Without thinking, we are shutting nature out, severing yet another link between ourselves and the wild world.

The contemporary zeal for sealing buildings against all elements and intruders is thus depriving swifts of the crevices they may have nested in for centuries. A breeding swift will return to the same hole in the same house in the same street where its seldom-used feet touched down the previous year. This is what instinct impels it to do: to stick to the map in its memory; to navigate back to the exact place it has claimed, won and defended in order to rear its young. Unfortunately, growing numbers of swifts return to find their holes blocked off.

There are still dozens of swifts around town, but I know there are fewer than there used to be. People have told me of places where they used to see them, such as the Victorian Assembly Rooms, reincarnated as a nightclub for many years then converted to apartments with a renovation that left no holes for swifts. It is the same story in towns and cities all over the northern hemisphere. When they disappear from their old haunts, house by house, street by street, life ebbs away.

Roof renovation can easily be swift-friendly but it rarely is. In my home town I decided to find out which buildings were used by the birds, then to try and ensure their holes were retained when scaffolding appeared, before renovation work started. To my amazement, around a dozen people joined me on the first outing, fellow enthusiasts keen to find out more about this wondrous bird and its habits.

An hour before sunset is the best time to look: parent swifts will be snapping up the last insects of the day, a late supper for their nestlings. We scan the skies, listen for high-pitched cries and follow. Always on these evenings we are led into the older parts of town, along streets of Victorian terraces, above shops in the centre, down back alleys of old warehouses and beyond. Ventilation used to be regarded as essential in building construction, to prevent timbers from rotting. This ensured plenty of cavities for swifts and bats. With the advent of new materials, such as concrete and plastic, buildings started to be sealed off from the air, plastic soffits and fascia boards replacing wooden ones, with little chance of gaps opening up. Damp courses prevented moisture entering, and building regulations were drawn up, stipulating that ventilation holes must be bird- and insect-proof. Inevitably, this brought serious consequences for swifts and other hole-nesting creatures.