Found: the little-spotted woodpecker

Watching something that's disappearing is a curiously moving sensation. You feel you must focus on it as hard as you can, while you can, for you may not have the chance to see it again.

Watching something that's disappearing is a curiously moving sensation. You feel you must focus on it as hard as you can, while you can, for you may not have the chance to see it again.

At least that's what it felt like this week when The Independent, after more than a year of trying, caught up with Britain's most rapidly vanishing bird, the tiny and elusive lesser spotted woodpecker. After a long wait deep in a Cambridgeshire wood, staring at a nest hole the size of a 50p piece near the top of a dead birch tree, we finally glimpsed a bird few people ever see - and which, if present trends continue, people in Britain may never see again.

Dendrocopos minor is at the top of the list of a whole suite of birds of the woodlands, such as the spotted flycatcher and the willow tit, whose populations are tumbling at a rate that threatens them with extinction - and no one knows why. Over the past 40 years, Britain's farmland birds such as the skylark and the grey partridge, have suffered massive declines, but the major cause is known - the intensification of agriculture - and policies are in place to bring them back. With woodland birds, whose declines have only recently been registered, the cause is a mystery.

The problem is perhaps most difficult of all with the lesser spotted woodpecker, because very little is known about the bird to start with. Quite uncommon and very small - about the size of a Mars bar, and weighing less than a packet of crisps - it lives in the dense leaf canopy of woodland trees, and unlike its relatives, the great spotted and green woodpeckers, it virtually never descends to the ground. Shy and retiring, it does not feed on your lawn like the green woodpecker (which is doing fine); it does not visit your garden bird table like the great spotted (whose numbers are shooting up).

Attractive though it is - the male has a bright scarlet crown - the only people who ever see it are the birders or professional ornithologists who determinedly seek it out in spring, when it can be located by its call and by its drumming as it excavates its nest hole in dead wood. And even now, there is little detailed knowledge about its range, its nesting requirements or its preferred habitat for foraging. So the Royal Society for the Protection of Birds is launching a research project to try to understand the species, so that the causes of its decline may eventually be teased out.

More than a year ago, The Independent asked the RSPB to find us a lesser spotted we could view and photograph; this week they provided one. The pilot study for the research project is focusing on a nest deep inside Monks Wood near Huntingdon, the largest wood in Cambridgeshire.

Derek Gruar, an RSPB conservation scientist, found the nest in March after about 30 hours of searching through the dense woodland of oak, birch and hazel coppice, tracking the male bird down by its drumming. Mr Gruar and his colleagues have succeeded in netting and ringing the male, and fitting a minuscule transmitter to its tail.

When we were shown the bird's tree in the dark woodland, it took a few minutes, even with binoculars, to spot the hole; and then there was a long, long wait. But eventually a shadowy form flickered into view from out of the leaves and there wasDendrocopos minor in all his tiny glory, come to feed his chicks with a beakful of grubs. He landed on the birch trunk above the nest, shinned backwards down the bark, and disappeared into the tree. Then after a few seconds the bright scarlet crown appeared in the nest hole, the bird took a quick peek left and right, and was away again.

It was memorable to a degree - not least because it was a sight that may not long be with us. "Any bird whose population has crashed by 80 per cent has to be a cause of serious concern," said Mr Gruar. "And the main problem is, we don't yet know what the problem is."

¿ Anyone who thinks the idea of wild birds going extinct in England is far-fetched, should be aware that there are several gloomy precedents: 30 years ago we lost what was then the fourth of our woodpecker species, the wryneck. This small brown bird - named for its weird ability to turn its head through more than 180 degrees - started to disappear after the Second World War. Its population of perhaps 400 pairs in 1954 shrank to fewer than 50 by 1967, and by 1974 it had stopped breeding in England.