Bird census exposes 75-year demise of sparrows

When he counted them first, in 1925, the house sparrows of Kensington Gardens numbered 2,603. When Max Nicholson watched as they were counted again on Saturday, there were eight of them.

When he counted them first, in 1925, the house sparrows of Kensington Gardens numbered 2,603. When Max Nicholson watched as they were counted again on Saturday, there were eight of them.

Seventy five years on, almost to the day, the grand old man of Britain's environment movement, now 96, returned to the London park where as a young man he carried out the UK's first scientific bird census, to see it repeated. And he could only marvel at its most remarkable finding.

Saturday's count, by the Royal Parks Wildlife Group, illustrated more vividly than anything has yet done the near-extinction of the house sparrow, mysterious and unexplained, from Britain's city centres. While numbers of robins, blue tits, blackbirds and many other small songbirds have stayed more or less stable over many decades, the bird that once outnumbered all others has now virtually gone.

"It's quite amazing," Mr Nicholson said, leaning on his walking stick and surveying a sparrowless landscape from Peter Pan's statue to the Albert Memorial. "I thought the sparrow numbers might go down, but I never, never imagined a decline like this. I never thought I would come back in a new century and see it." He laughed. "But then I certainly didn't think I'd be alive at this horrible age."

Max Nicholson contributed more to conservation in Britain during the 20th century than any other individual: in 1949 he helped set up (and, later, for 14 years ran) the world's first statutory conservation body, the Nature Conservancy, and in 1961 he launched the first of the world's great green pressure groups, the World Wildlife Fund (now the Worldwide Fund for Nature).

Along the way he led both the British Trust for Ornithology and the Royal Society for the Protection of Birds, and was founder editor of the ultimate authoritative European bird book, the nine-volume Birds of the Western Palaearctic.

But he was a mere stripling of 21, an unknown but ambitious writer on natural history, when he decided to carry out a complete census of the birds of Kensington Gardens, the westward extension of Hyde Park to Kensington Palace.

American ornithologists had used the technique with great success to show how important the idea of territory was for birds to breed successfully - each bird needs an area big enough to gather food for itself and its family - but it had never been done in Britain. Max Nicholson enlisted the help of his brother Basil, and dividing the gardens into 19 sections, on 2 and 4 November 1925 they spent a total of nine hours counting all the birds, employing various strategies to avoid double-counting.

They found 30 species and a total of 3,982 birds: house sparrows were most numerous at 2,603, followed by starlings (411), black-headed gulls (289) woodpigeons (241) and mallard (240). There were 27 blue tits, 19 great tits, 21 blackbirds, 16 robins and six wrens.

Mr Nicholson believed the counts were accurate to within 10 per cent, and an indication of this was the repeat of the census a month later, when the number of birds counted was only 203 fewer, with the sparrow figure being 2,595, a difference of only eight individuals. The census was repeated; the next one in 1948 showed a substantial drop in sparrow numbers to 885,thought to reflect the inter-war disappearance from London's streets of the horse and spilled grain associated with it, which provided much sparrow food.

But after that, the Kensington Gardens house sparrows were more or less on a plateau, if a gently declining one: 642 birds in 1966 and 544 in 1975, the 50th anniversary census, which Mr Nicholson himself took part in. It was when the Nineties arrived that the true crash came. The 1995 census, organised by Royal Parks Wildlife Group chairman Roy Sanderson found only 81 birds remaining.

Yesterday's count, by three teams of two observers, each organised by Mr Sanderson once again, was the more remarkable for recording 50 species, the highest number ever, including five new ones - red-crested pochard, stock dove, green woodpecker, fieldfare and brambling - proving Kensington Gardens remains a fertile habitat.

But sparrows almost did not figure. Two of the teams found none, until observers Doug Boyd and Graham Giddens located a flock of eight birds in the neighbourhood of Kensington Palace. The count was carried on a sunlit morning, a respite from the current spate of downpours, and a major difference from the same week in 1925 was that most of the trees were still covered in leaves. Seventy-five years ago, there were bare. "Global warming!" Mr Nicholson said, referring to the belief that climate change is making autumn later and later.

His own unusual theory for the sparrow decline, as The Independent has recorded, is that the species has a suicidal tendency - if numbers drop too low, they simply cease breeding. Roy Sanderson thinks they may be suffering from attacks by parasites. Denis Summers-Smith, the world expert, thinks motor-vehicle pollution may be killing off the insects they need to feed their young. Whatever the reason, Saturday's count illustrates that they are on a steep slide to extinction.