Birdsong to be broadcast from rooftops in hope of swift return

The song of the swift is to be broadcast across London's rooftops in an attempt to increase numbers in the city.

Islington council has installed speakers in the belief that recordings of the song will attract passing birds to make it their home.

For four hours each afternoon and early evening they will play the cries and screeches of the swift from speakers on buildings in Upper Street. The tapes will be loud enough to be heard by passers-by. Hundreds of bird boxes have been set up across the borough to encourage swifts to nest.

This is the first experiment of its kind in London. At the end of the Eighties there were 100,000 breeding pairs of swifts in the capital. There are now around 50,000.

Greg Foxsmith, the council's environment head, said: "Swifts are amazing migrant birds. We're constantly striving to create a greener borough and encouraging birds to nest in Islington is just one way of doing this."

The swift calls will be played from 4pm to 8pm daily.