RSPB to run huge survey on decline of sparrows

A national survey will be run next month to investigate the decline of Britain's most rapidly disappearing bird, the house sparrow.

The Royal Society for the Protection of Birds (RSPB) is hoping that more than 100,000 people will take part to assess the numbers and whereabouts of the birds. Volunteers are being asked to count sparrows in their gardens at any time between 3 May and 11 May. The survey is being organised along the lines of the RSPB's annual Big Garden Birdwatch, which this year involved more than 300,000 people counting the birds in their garden for an hour during the last week in January.

That survey found that sparrows were still Britain's most numerous garden bird after the starling – but in real terms their numbers had fallen by more than half since 1979.

The survey is being run at the same time as a similar house sparrow poll by the British Trust for Ornithology (BTO), a research organisation. Because the smaller-scale BTO survey is much more detailed, the hope is that the two studies will complement each other.

"We are keeping our survey comparatively simple, but we are hoping for a really massive response," said Richard Bashford of the RSPB. "We're looking for pretty basic information, from the maximum number of people. One advantage is that we can get lots of good information from less populated areas of the country."

British house sparrows have fallen in number from about 12 million pairs to about 7 million pairs between 1970 and the present day. In some cities, especially London, they have disappeared for reasons that are still not known.

For the past three years, The Independent has been offering a £5,000 prize for the first scientific paper to explain why house sparrows are disappearing from urban areas.

* People who wish to take part in the RSPB survey can telephone the house sparrow hotline on 0870 6010215, or visit www.rspb.org.uk