Leading article: How to meet the demand for new homes the green way

All housing development within a 300-square-mile area to the west of Greater London has ground to a halt. Since last October, the construction of thousands of new homes across the counties of Berkshire, Hampshire and Surrey has been on indefinite hold. This follows a ruling last autumn by English Nature, the Government's wildlife protection agency, that all house building within five kilometres of the Thames Basin heathlands should put on hold for the good of three species of rare bird that inhabit the area.

The reaction of developers has been less than understanding. Why, some have demanded, should building work be held up for the sake of a few wild birds? The answer is obvious to anyone who has visited the heathlands. This is not just some anonymous, over-cultivated corner of rural England. The lowland heaths - covered by heather, gorse bushes and silver birch trees - have a rare, wild beauty. They are also home to a rich array of birdlife. The nightjars, woodlarks, and Dartford warblers, which English Nature has moved to protect, are the ecological jewel in the area's crown. These heathlands are part of Britain's natural heritage, and English Nature is right to put a priority on their survival.

This is no overreaction. As Jim Knight, the Environment minister, has pointed out, this EU Special Protection Area already has more urban development around it than any other SPA in Europe. It is at serious risk of being swallowed up by the growth of residential developments in the South-east. The environmental impact of new housing should not be underestimated either. Studies have shown that the dog walkers and domestic cats that spill out of residential estates have a devastating effect on the heath's rare bird population (which nest on the ground, or in low bushes). Simply put: more houses in the area will mean more harmful visitors, of both the animal and human variety.

This battle between the push to develop and the need to protect our natural environment is likely to be the first skirmish in a long war. Some 580,000 new homes are to be built in the South-east over the next 20 years. More friction between environmentalists and developers is inevitable as this ambitious programme proceeds.

We would argue that some additional building is necessary. The rate of house building in the UK is at its lowest level since the 1920s. Many workers, and not just in the public sector, find themselves priced out of the market in the South. In the long term it would be preferable for the Government to encourage people to move to the rest of country, where housing tends to be cheaper and more plentiful, to take the pressure off the region. But in the short term the Government has little choice but to cater for the demand for more housing in the areas around London.

This need not be ecologically disastrous. Not all the green-belt land that has been earmarked for residential development is as valuable as the Thames Basin heaths. And in the case of the heaths, English Nature is in the process of devising a reasonable compromise. House builders will be asked to develop new public spaces alongside any land developed at the edge of the heath. This will provide alternative places for recreation, so as to minimise the effect on the heath itself. This is an environmental equivalent of requiring developers to build a quota of social housing on any new private development. Local authorities and developers should seize upon it as the sustainable way forward. Let us hope that this becomes a model for future green development; we will certainly need one in the coming years.