Residents say a wildlife corridor near Oxford's Churchill Hospital is being destroyed by the hospital trust.

They claim important wildlife habitats are being swept away by diggers as part of a scheme to transform the wooded area around Boundary Brook into "parkland."

The Oxford Radcliffe Hospitals Trust undertook to tidy up the overgrown area on the edge of the Churchill Hospital's Headington site. It says the community project has involved clearing the brook of debris and planting wildflowers to regenerate the natural grassland habitat.

Some of the work has been carried out by offenders doing Community Service, with the site visited last month by the Home Office Minister Baroness Scotland.

But residents' groups say the trust has overstepped the mark with its enhancement scheme on the banks of the brook.

Graeme Salmon, a retired Oxford University physicist of Hill Top Road, warned: "The wildlife corridor is going rapidly. Tidying in woodland may be needed occasionally. But this seems to be converting the eastern riverbank of the Boundary Brook into parkland."

Dr Sietske Boeles, of Divinity Road Residents' Association, said: "This is a sensitive area. It is designated as a wildlife corridor and is close to an ecologically fragile Site of Special Scientific Interest.

"We are concerned about the destruction of habitats and the impact on drainage from the work, as well as the introduction of alien plant species such as ivy. A footpath has also been redirected. Sound rules and regulations exist to safeguard important habitats, to monitor hydraulic changes and floodrisk and to maintain rights of way.

"Yet these are ignored as soon as major development work starts."

Prof Floris van den Broecke, of Hill Top Road, said the work had added to fears about proposed development at the nearby Warneford Meadow, on the other side of the brook, which is now the subject of a local protest campaign.

Project manager Vicki Holcroft said the scheme had been approved by the city council and aimed to benefit the local community.

Ms Holcroft added: "We are happy to meet residents and have stopped work so we can take account of their comments."