The Swift is a medium-sized aerial bird, which is a superb flier. It evens sleeps, eats and mates on the wing! It is plain sooty brown, but in flight against the sky it appears black. It has long, scythe-like wings and a short, forked tail. It is a summer visitor, breeding across the UK, but most numerously in the south and east. It winters in Africa.
Swifts arrive at the beginning of May having travelled thousands of miles in a matter of days. Young birds may have been flying continuously for many months if not years before returning to the place of their birth. They will spend a season or two as “prospecting birds” checking out potential future nesting spots until they reach sexual maturity at three years old. Long-lived, mature birds mate for life and return to the same nest site year on year typically in the eaves of old buildings.
A number of unusual adaptations allow them to live on the wing, they can let half their brains go to sleep while the other half takes care of the flying, they bathe by flying slowly through rain, they drink by flying low over water and sipping and the eat huge amounts and varieties of flying insects. They range far and wide for hundreds of miles in search of food on a daily basis if necessary and if they are away from the nest for long the chicks enter a torpid state until the parents return to conserve energy.
As soon as the chicks are fledged they leave, usually in August, but the adults make their presence known screaming overhead often in large numbers.
Modern building practices make it increasingly difficult for swifts to find nesting sites and their numbers have been declining as a result.
Average lifespan: 9 years
Classified in the UK as Amber under the Birds of Conservation Concern 4: the Red List for Birds (2015).