Blog written by Daniel Kronenberg

As I’m writing this, in mid-March, over The Congo Basin in central Africa millions of swifts are gathering before returning to their breeding grounds of Europe and Asia. They have been constantly in the air since last August, feeding in the day and sleeping in the sky at night. In fact, for the first 2 to 3 years of their lives, before they breed, they never land.

Swifts are now predominantly reliant on nesting spaces in buildings. Previously they would’ve nested in holes in trees and crevices in cliff faces. They seek out the nooks and crannies under our eaves or holes in walls and pairs return loyally to the same sites year after year. Swifts mate for life, unless one partner dies. For a small bird, they live a remarkably long time. On average they live about 7 years, although some have been known to live up to 20 years.

In a very rudimentary nest, made out of hair, leaves or any other material which they can find in the sky, the female lays between 1 and 4 eggs. The young swiftlets remain in the safety of the nest for 6 - 8 weeks and then launch themselves into the sky flying perfectly from that moment and fully independent of their parents.

The Common Swift, like many of our birds, is not as common as it once was. In December 2021 it was added to the red list of Birds of Conservation Concern - since 1995 swift populations, in the UK, have fallen by 58%. This may be partially due to insect decline but more likely connected to the lack of nesting spaces as old buildings are renovated and nesting sites blocked off. Also, our new buildings are well sealed, for insulation purposes, denying new opportunities for swifts to nest in. The decline in Wiltshire is noticeable more in villages where numbers are extremely low or non-existent, although some towns have very minimal numbers compared to a few decades ago.

Local groups, such as ours - Salisbury and Wilton Swifts (SAWS)- are working to help halt or even reverse this rapid decline by installing nest boxes and encouraging local authorities, builders and developers to install swift nesting bricks in new builds.

More about our work can be found at You can also join us on Facebook – search Salisbury and Wilton Swifts or follow us on Twitter @And Swifts