More than 40 per cent of England's best wildlife sites are in poor condition, the most comprehensive survey of its kind ever undertaken will disclose today.
Many treasured woodlands, heathlands, grasslands, lakes, rivers, fens and shorelines are suffering from a catalogue of problems. These range from overgrazing by sheep and deer to industrial and agricultural pollution, from lack of scrub clearance to flooding, according to the survey from English Nature, the Government's wildlife conservation adviser.
Ministers have pledged to return 95 per cent of these sites to favourable conditions by 2010, but meeting this goal will involve a "huge effort" from everyone involved and millions of pounds of increased funding, English Nature warns.
Although they have been officially "notified" as Sites of Special Scientific Interest (SSSIs) for their wildlife or geological importance, the great majority of these areas are not owned by the Government but are in the hands of 32,000 farmers and other landowners. Their co-operation (and a willingness to provide funding) will be needed if improvements are to be made.
English Nature estimates that its budget for land management agreements will have to rise from £10m per year now to £24m per year by 2010 if the Government's 95 per cent target is to be hit.
The definitive survey of all 4,112 English SSSIs, which cover just over one million hectares or 7 per cent of the land surface of England, took six years to carry out and is believed to be the most extensive such exercise ever attempted anywhere in the world.
It ranged from the smallest - the seven-square-metre roof space of a barn in Gloucestershire, a roost for the lesser horseshoe bat, to the largest - the 62,000 hectares of the Wash, which are coastal and marine habitats of international importance for migratory and wintering birds. And it found that only 58 per cent of them were in favourable or recovering condition.
Of the 42 per cent in trouble, rivers and streams, chalk grassland on mountains, moorland and bogs are the habitat types with the largest proportion of their area in poor ecological state.
Rivers come out worst: the 33 English rivers and streams scheduled as SSSIs have more than two-thirds of their total area in poor condition, the survey notes, and this includes stretches of some of the most prestigious and beautiful rivers in land, the chalk streams of the southern counties such as the Test, the Itchen and the Hampshire Avon.
Intensive farming is the worst problem the rivers face, in particular in the form of "diffuse" pollution (pollution from more than one source) by agricultural chemicals, which disturbs the balance of plant growth. Direct industrial and sewage pollution and overabstraction of water are other threats.
Overgrazing by sheep, whose numbers soared when EU agricultural payments increased with every extra animal, is a further problem affecting many habitats, especially the moors in the English upland national parks, such as the Lake District, the North Yorkshire Moors and Dartmoor.
More than two-thirds of the area of these moorland SSSIs (officially classed as uplands heath) is in trouble, with sheep grazing out the heather; a similar proportion of bogs is also in trouble.
Another severe grazing problem is coming from deer, especially in woodlands. "There are now more deer than English woodlands can sustain," said an English Nature spokesman. "Deer management is becoming a bigger and bigger issue."
Deer eat the plants around the base of trees, damaging the habitat of many small mammals, birds and insects. The disappearance of nightingales from some southern counties of England is thought to be due to deer eating the scrub in which they like to nest.
The general thrust of the report is that funding for management agreements with landowners will have to rise if more sites are to be restored.
CASE STUDY THE OUSE WASHES
To see a Site of Special Scientific Interest that is in trouble, take a trip to the Ouse Washes in Cambridgeshire.
On the map, the site looks like the thinnest of pencils - a dead-straight strip of grassland half a mile wide and 20 miles long, with a dyke and a river channel on either side, in the flat Cambridgeshire Fen country. Ely Cathedral stands on the horizon.
For much of the past 50 years, this thin pencil has been one of Britain's most important breeding areas for wading birds, especially the black-tailed godwit, Limosa limosa .
Striking birds, chestnut-red in their breeding plumage, black-tailed godwits were driven to extinction in the 19th century, but in 1952, a few pairs came back to nest on the Washes, and founded a new British breeding population. And for 30 years they flourished.
Understandably so. The washes are a gigantic flood reservoir, constructed by the Dutch engineer Cornelius Vermuyden in the 17th century to help drain surrounding fenland for agriculture and to store surplus floodwater from the Bedford Ouse.
Under water every winter, in spring they dry out, and the damp grassland is a perfect breeding ground for wading birds, including rarities such as ruff and spotted crake, besides the more familiar redshank, snipe and lapwing. In winter, thousands of waterfowl throng the washes, including whooper and Bewick's swans from Iceland and Siberia.
Much of the Washes are owned now by the Royal Society for the Protection of Birds and the Wildfowl and Wetlands Trust. But in the early 1980s, the floods began occurring in the spring as well as the winter, washing away the godwits' nests.
The Ouse Washes godwit population tumbled from 65 pairs in the early 1970s to only four pairs in 2003.
"More water is coming down from as far away as Milton Keynes," said Dr Mark Avery, the RSPB's director of conservation. "There is a lot more agricultural drainage, and a lot more concrete - most of Milton Keynes wasn't there 30 years ago."
The RSPB can do little to stop the spring flooding, which would take the intervention of other bodies, such as the Environment Agency, with new engineering works or a new management plan for the Ouse.