A protected colony of water voles are being brought into London in the hope the mammals take to city life.

The water vole, immortalised as Ratty in Wind in the Willows, is threatened with extinction in the wild as its habitat declines and predators increase.

During the past decade the water vole population has been reduced by 90% nationwide.

But the Mammals Trust UK is reintroducing a colony of 200 captive bred water voles into Bedfont Lakes Country Park, near Heathrow Airport.

'Incredibly excited'

In the wild the mammals' riverside habitat has been destroyed and there has been an inexorable spread of predatory American mink.

But Bedfont Lakes is naturally protected from mink so it is hoped a viable water vole population will be able to be established.

It follows the success of a trial release of water voles at the London Wetland Centre in Barnes last year.

Paul Morgan, ecology and conservation ranger at Bedfont Lakes, said: "We are incredibly excited about having the water voles here.

"It's such a new chapter for an area that in the last century has been used as gravel workings and a landfill site.

"Hopefully our participation in the project will prompt other such sites to think about reintroducing animals to their land and encourage further programmes like this."