Norfolk Wildlife Trust Reserves Officer, Robert Morgan, shares some incredible facts about swifts and gives some hints about where to see these fascinating migrant birds in Norfolk.
There can be few British birds as unique and uncompromising in lifestyle as the swift. Much of our rural folklore concerning wildlife is, at best, exaggerated or - let's be frank - untrue. The swift, however, is the exception that delivers on its many bizarre and extraordinary 'myths'.
It is true that if a swift lands on the ground it is likely to die; its short, stumpy legs and long sickle-shaped wings preventing it taking off. They can climb to thousands of feet in the air: sleeping on the wing they will doze as they glide down, their in-built altimeter waking them as they descend.
They feed, drink and even mate on the wing. They can fly around whole weather systems with ease and swifts nesting in London think nothing of spending the evening catching flies in Norfolk, returning to their chicks at daybreak. They may cover well over a million miles in a lifetime, which can be up to fifteen years or more.
Swifts are very much birds of our villages and towns, even nesting in the centre of major cities. Being one of the last migrants to arrive, it is truly summer when swifts scream their familiar shrill whilst circling in a rapid, seemingly co-ordinated, chase over sun-soaked suburbia. Formerly a bird restricted to nesting in caves or the crevices of cliffs, they need to provide both cover for their offspring and be able to launch themselves straight into the air from the nest. An alternative has been unintentionally provided by us in the form of gaps under the tiled roofs of Victorian terraces or the slats of church belfries.
Exceptional for birds, swift nestlings have the ability to slow their metabolic rate into quasi-hibernation. In cold or wet conditions, when flying insects are scarce, the adults may have to travel great distances to find food. The young will fall into a torpor until conditions improve and their parents return. The fledglings are completely independent on leaving the nest, making their own way to Central Africa and staying there until fully mature at about three years of age; in that time they never touch a solid object, remaining constantly airborne.
A great place to discover the wonderful sight and sound of parties of swifts is NWT Thorpe Marshes. This compact nature reserve brings a little piece of the Norfolk Broads into Norwich. Boasting a mixture of scrub, dykes and fen, it is a great place for urban swifts to feed.
Along with house martins and swallows, they can be seen hawking insects over the marshes. This allows an opportunity to try and distinguish between these three aerial specialists. The swift is larger, dark brown with a small white bib, its cigar shaped body and long sweeping wings are distinctive. In silhouette the hobby is the only other bird that resembles it. Often seen at Thorpe Marshes too, this fast flying falcon is the swift's only predator, but experienced adult birds are rarely caught.
Swifts maintain a close partnership and a bonded pair will remain faithful to a nest-site for years, with following generations often continuing its use. Contemporary housing and building maintenance can deny swifts nesting opportunities, however more enlightened developers are now providing purpose built swift cavity brickwork in modern buildings. You can also take action for swifts by installing specially designed boxes under the eaves of your own home. Patience may find that these fascinating and entertaining birds will one day occupy them, bringing, I'm sure, great joy at their arrival each summer.
Header image: Swift by Nick Appleton