Migrating swifts loyally return every year to nests in buildings, study finds

Migratory swifts loyally return every year to their nests in buildings, according to a study, underlining the importance of providing the endangered birds with hollow nesting bricks if traditional nest sites are lost to renovations. The swift, which is on the red list of conservation concern, is one of Britain’s most threatened species, having declined in number by 70% since 1995 because of the loss of nesting sites, often when old buildings are re-roofed or given better insulation. While Scotland this year made the installation of swift bricks – a simple hollow brick – a legal requirement in new buildings, the government in England has repeatedly refused to oblige builders to include a £35 swift brick in every new home. Scientists for the RSPB studied 190 different swifts from 243 nests over 15 years in a Dartmoor village and found that 94% of the birds reused the same nesting site as the previous year. The 15-year study found that swifts, whose screaming parties over towns and cities are a much-loved sound of summer, have greater loyalty to their nest site than a previous partner, with only six out of 10 (59%) birds pairing with the same partner. Sometimes, as nest camera footage vividly reveals, there are fierce debates over the use of a nesting box. Three swifts fight over the use of a nest box – video Researchers collected data from swifts breeding in nest boxes in Drewsteignton, Devon. …