The water vole is disappearing across Britain

Numbers of the creature - which inspired the character of Ratty in the children's classic - have been declining rapidly in most parts of the UK.

The water vole was depicted living a life of ease on a sleepy riverbank in Kenneth Grahame's 1908 novel.

Now the creatures have been discovered thriving at higher altitudes than usually expected and apparently seeking refuge underground.

Water voles have been found at RSPB Scotland's Abernethy Forest Reserve in the Cairngorms, where they have not been seen for more than 12 years.

Ecologist Andy Amphlett said: "Significant numbers of water voles have been found in water courses at the head of burns.

I sat down with the surveyors and promised them that I'd eat my hat if they found any water vole communities underground Desmond Dugan Forest manager

"These can be very narrow burns often flowing underground or covered by vegetation.

"These communities are subterranean, very different from their Wind in the Willows image."

Mr Amphlett said water voles had been rapidly disappearing from lowland Scotland.

"In the last five to 10 years it has become apparent that in the Cairngorm area the species still occurs in considerable numbers," he added.

"Here they have been found on hillsides at altitudes as high as 900 metres."

RSPB Scotland forest manager Desmond Dugan said the discovery at Abernethy had taken him by surprise.

Original sites

"I sat down with the surveyors and promised them that I'd eat my hat if they found any water vole communities underground," he said.

"Well, it looks like I'm going to have to find some seasoning for my deer-stalker."

The water vole population has disappeared from about 94% of their original sites in Britain.

The creature is threatened by habitat degradation, water pollution and predation by mink.