Europe and Central Asia
16 Aug 2010

Swift box success at BirdLife's UK office

By nick.langley

Like other bird species which migrate between Europe and Africa, Common Swift Apus apus numbers have been falling rapidly. According to the UK Breeding Bird Survey Swifts in Britain declined by 29% between 1995 and 2008 [1]. Among the problems Swifts face are the property boom of the post-1945 era –and the more recent passion for home makeovers and renovation. While very occasionally Swifts will nest in natural sites such as crevices in cliffs or old trees, they have become almost entirely dependent on buildings for their nest sites. But they need access to the flat surface at the top of the wall under the eaves, or to the roof space, and these tend to be features of older houses, particularly those built before 1919[2]. Modern building practices and building regulations (such as loft conversions, and insulation standards which result in gaps being sealed) almost always deny access for Swifts. The BirdLife Secretariat occupies a modern two-storey office block in Girton, on the outskirts of Cambridge, a building with no opportunities for breeding Swifts. But with the help of local Swift enthusiasts, Swifts have been encouraged to prospect for sites in custom-built nest boxes. There has been a satisfying degree of success in the last few years in persuading Swifts to adopt nest boxes installed in churches, a school and on peoples homes around Cambridgeshire. Installing the BirdLife nest boxes required the permission of the building’s owner, so responsibility for the project fell on the shoulders of the Secretariat’s office manager, Trish Aspinall. “I emailed the Landlord’s agents with as persuasive an argument as I could muster, and they gave a very positive and helpful response.” Eight boxes in two cabinets were erected under the edge of the roof. Although Swifts are not known to nest anywhere within the near vicinity of BirdLife, the birds were attracted by playing their calls through speakers beneath the boxes. Trish Aspinall begged and borrowed a CD player, amplifier and speakers from BirdLife staff and friends. A timer from her husband’s toolbox ensured that calls would only be broadcast between 0600-0800 and 1930-2130, so as to minimise disturbance to the neighbours in working hours. “By early June, we were in business!” On the 1st July, Swifts were seen entering the boxes. “We’d placed ‘tell-tales’, match-sticks across the entrances, and three of them had been moved. We regularly had screaming parties around and over the building. By late July it was very clear the Swifts were quite well acquainted with the nest boxes. I actually think there has been a lot more activity than we realise, as of course we can’t watch the boxes all of the time.” Among the last of migratory birds to arrive, Swifts are the earliest to leave, and before the end of the first week in August the local breeding birds were on their way back to Africa. It was time to open the boxes and find out what the birds had been doing. “The Swifts had made a nest in one box, and half a nest in another. All the material for the nest has to be gleaned from the air [3]. Our birds had used feathers, floating seeds and elongated tree seed pods which they stuck down with their saliva” said Trish.

A check of the Common Swift boxes revealed a nest. (photo: T Aspinall)

“We were not expecting them to breed in Year 1”, she added. “We think all the activity in July was for building a nest for next year. This means, if the birds survive migration, it is more than likely that they will return to breed next year and carry on the show!”

A second nest has been started in one of the other nest boxes. The nest is built using saliva. (photo: T Aspinall)

Marco Lambertini, Chief Executive of BirdLife, said: “it is most gratifying for us to be involved in the conservation of a species right here on our own building”. For the decline in Swifts to be arrested and even reversed it is essential that:

  • Existing nesting places are preserved wherever possible
  • If re-roofing, make new nest access holes to match the old ones exactly
  • In new buildings provide internal nest spaces
  • As a last resort fit external nest boxes

Swift enthusiast and BirdLife Rare Bird Club member, Dick Newell, said: “making a place for Swifts costs little. Swifts will use DIY or commercially-available nest boxes which can be installed in old or new buildings. Playing the Swift CD is key to success”. There is a growing network of Swift enthusiasts in the UK and Europe, working with parish, local and city councils, and with church authorities and other managers of historic buildings likely to provide the last refuges for Swifts. For more details, see, where you will also find advice for homeowners, architects and developers and local authorities on making room and building homes for Swifts. You can also get involved in surveys, see [1] The Breeding Bird Survey is carried out by the British Trust for Ornithology (BTO), Joint Nature Conservation Committee (JNCC) and the RSPB. The decline in Swift populations is also clearly demonstrated in the figures returned by the BTO/RSPB/BWI/SOC Birdtrack survey between 2002 and 2009. [2] According to a survey by the RSPB, while 10% of UK homes built before 1919 can house Swifts, the figure for inter-war housing is 7%, and for post-1944 housing only 1.4%. [3] Swifts spend almost all their lives in the air, and roost on the wing at up to 3000 metres. They feed, drink, mate and sleep on the wing, and normally only land to breed. A young Swift may spend its first two or three years in constant flight before it breeds. Photo credit: Swift leaving nest box by fs-phil/flickr

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