Swifts flying over rooftops

Swift migration

Swifts are almost always in the air - they only ever land at their nests.

Where swifts spend their time

Swifts need warm weather to provide a constant supply of flying insects, so they spend only about three months in the UK each year. They arrive from central Africa in early May and make their nests of straw and saliva in church towers and other tall buildings. 

Young swifts remain in the nest for 37–56 days, depending on the weather conditions. If it gets too cold, they fall into a sleepy state called torpor – a bit like hibernation – during which they don’t feed until conditions improve. Youngsters are independent as soon as they leave the nest, and set out immediately on migration. 

Swifts start their return journey in mid July, before nights become too cool. They can’t roost overnight during the journey, like swallows do, so they travel quickly. One young swift that left its UK nest on 31 July, was found in Madrid (Spain) on 3 August.  

By mid-August, most swifts have reached central Africa. They do not spend the winter in one place, but travel around according to food supplies and weather conditions. Swifts can live up to 21 years, so one individual may fly more than one million kilometres during its lifetime.