Restoring the glory of waterworld

A project to replace arable fields with pools and reedbeds will create habitat for threatened wildlife in the Fens. Michael McCarthy reports

The Fens are coming back. Southern England's long-lost great wetland is to be recreated on a massive scale by several huge restoration projects which will turn farmland into watery wilderness.

The Fens are coming back. Southern England's long-lost great wetland is to be recreated on a massive scale by several huge restoration projects which will turn farmland into watery wilderness.

In terms of putting back the countryside to the way it once was, Britain has seen nothing like it. The various schemes aim to recreate a total of nearly 25,000 acres of wetland - continuous stretches of reedbeds, marsh, wet grassland and lakes - which, it is hoped, will not only be teeming with birds and mammals, wild flowers and butterflies, but will provide a much-needed amenity which people can wander through on foot, on bicycles, sometimes on horseback or even in boats.

Cambridgeshire, where most of the projects are set, is the poorest country in England for wildlife and rural recreation. It has less than half the national average of publicly accessible countryside, and the lack of it will become even more telling with the large-scale housing development now targeted at the region. Up to 200,000 new homes are expected by 2025.

The county is such a disappointment for wildlife and worthwhile country walks because it is given over to intensive agriculture, which is itself a direct result of the drainage of the Fens over the past 400 years. The peat of the drained fenland provides a very rich soil, which supports mile after mile of sugar beet, wheat and carrot fields, although as it dries out it is steadily shrinking and eroding.

The transformation has been immense. Once, the Fens covered nearly 3,000 square miles of the low-lying ground between Cambridge and the Wash, roughly bounded by Peterborough to the west and the dry Brecklands of Norfolk and Suffolk to the east. They formed a strange and impenetrable swampland which the local inhabitants, who lived by wildfowling, peat-digging and cutting reeds for thatch, learnt to walk through on stilts.

This was Britain's equivalent of the Florida Everglades, and a landscape of legends; it was from the Isle of Ely, deep in the Fens, that the mysterious figure of Hereward the Wake led his Anglo-Saxon resistance to William the Conqueror after 1066. But it began to disappear in the 17th century, when landowners brought over Dutch engineers skilled at draining large areas of marsh by cutting channels and dykes. The drainage continued steadily for two centuries and reached a peak with the draining of Whittlesey Mere near Peterborough, the largest stretch of open water in lowland England, in 1851.

More than 99 per cent of the Fens went, and a unique countryside disappeared. But what has been lost even more, conservationists now realise from the few fragments of natural fenland that remain, was a wildlife reservoir of unparalleled richness, supporting flourishing communities of specialised animals, birds, plants and insects, many of which are now rare, such as the water shrew, the bittern, the fen violet and the swallowtail butterfly.

The main restoration projects are centred on these remaining fragments, now islands of biodiversity in a sterile sea of sugar beet. Three in particular provide the focus - Wood Walton Fen, Wicken Fen, and the Ouse Washes. All have long been celebrated nature reserves, and all are now to expand.

Wood Walton Fen, in what used to be Huntingdonshire, is at the heart of the Great Fen Project, which is a partnership between English Nature (the government's wildlife advisory body); the Environment Agency; Huntingdonshire District Council and the Wildlife Trust for Bedfordshire, Cambridgeshire, North-amptonshire and Peterborough. Managed by the trust, the project aims to restore more than 9,000 acres of fenland from arable land between Peterborough and Huntingdon.

A similar scheme is envisaged for Wicken Fen, north-east of Cambridge, which is owned and managed by the National Trust. Here, the projected expansion is even bigger, aiming to restore 10,000 acres to fenland in a south-westerly direction, almost to the boundary of Cambridge itself.

Both these undertakings will take many years, perhaps decades, to complete, because the farmland concerned will have to be freely bought on the open market. The great Fen project may be the easier one, because there are fewer than a dozen landlords owning the land, two of whom, the Crown Estate and the Mormon Church, have 60 per cent of it between them. For the expansion of Wicken Fen, the National Trust will have to deal with 120 farmers.

But farmers may be increasingly willing to sell, because the peat soil of the drained fens is steadily blowing away as it dries, and the land will become increasingly unsuitable for agriculture. The first two new areas have already been acquired by each project, and fundraising is actively under way for the millions of pounds that will be required for the rest.

One of the reasons for the scale of the two projects is that in recent years conservationists have come to realise that small nature reserves sometimes do not work well. Habitat fragmentation, as the problem is known, means that small wildlife populations become isolated and cannot replenish each other.

The attempted reintroductions of two rare and beautiful butterflies, the large copper at Wood Walton, and the swallowtail at Wicken, failed because the present reserves were not big enough to provide an adequate supply of their food plants; water dock for the large copper, and milk parsley for the swallowtail. The large copper is now extinct in Britain; the swallowtail is restricted to the Norfolk Broads.

But when the extended reserves are in place, there is a good chance both species could be introduced again successfully, said Nigel Bourne, of the charity Butterfly Conservation. "We would look on it very favourably," he said. Nick Hammond, the Wildlife Trust director, said: "Habitat fragmentation has been one of the great ecological problems of the past century, and here we have the opportunity of creating really large-scale conservation areas."

The most exciting aspect of the Great Fen Project, he added, was the idea of creating amenities for future generations. "Most of us in our private lives are not big landowners and we can't plant trees that will look magnificent in 200 years. But this is something that is going to change the face of the countryside.

"Most nature reserves you can walk across in an hour. This is going to be somewhere where you can lose yourself for a day, and still come back for more."

The third major restoration project for the Fens centres on the Ouse Washes, a pencil-shaped strip of wet grassland a mile wide and 20 miles long near Ely. Laid out in the 17th century as a winter flood reservoir, this is now one of the most important breeding sites in Britain for wading birds such as snipe, lapwing, redshank and the rare black godwit, managed by the Royal Society for the Protection of Birds, and powerfully protected by European Union as well as UK law.

But the Washes have been flooding in summer as well as in winter, and many nests have been destroyed. Under EU law the Government is obliged to provide alternative nesting sites, and so it is making £14m available to fund the purchase of up to 3,000 acres of farmland where once again, wetland will be recreated. The Royal Society for the Protection of Birds has, in fact, recently created new fen with spectacular success at Lakenheath in Suffolk, on the Fens' eastern edge, where 350 acres of arable land has been turned into a booming wildlife reserve.

Mark Avery, the RSPB director of conservation, said: "Seven years ago, Lakenheath Fen was a carrot field growing a perfectly good crop, but now it is growing a crop of hundreds of pairs of reed warblers and sedge warblers, marsh harriers and bearded tits. That's how quickly you can do it.''

The RSPB is also restoring more fenland at Needingworth near St Ives, in co-operation with Hanson, the building materials company; in a wetland of nearly 1,800 acres it will create an 1,100-acre reedbed, which will be the biggest in Britain.