A LEADING North-East naturalist is urging councils and development agencies to preserve some of the region's brownfield sites as important wildlife habitats.

Terry Coult, conservation manager for Durham Wildlife Trust, said Government guidance was to develop brownfield sites, such as pit heaps, to protect the greenbelt - something it supported.

However, writing in the trust's magazine, Durham Wildlife, he said: "The down side is that some of our brownfield sites are a quantum leap better for wildlife than are our greenfields.

"Redundant and ignored for many years, with an impoverished, and sometimes polluted, substrate which can hardly be called soil, many brownfields have developed a diverse mosaic of flower-rich, sparse grassland and bare areas, with associated invertebrates, most notably butterflies.

"Greenfield sites tend to be designated for landscape values and are often intensively managed green deserts supporting little wildlife."

The Government wants 60 per cent of business, housing and recreational development achieved on brownfield land.

Mr Coult said planning regulations allowed brownfield land to remain untouched where it had become part of the natural landscape with conservation significance.

He said: "It would be good to see authorities using some brownfield sites for housing, and incorporating the best into long-term managed landscapes, green networks and linear open spaces."