Swifts need warm weather to provide a constant supply of flying insects, so they spend only about three months in northern Europe each year. They arrive from central Africa in early May.
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. Youngsters are independent as soon as they leave the nest, and set out immediately on migration.
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.