French in a hole as toads halt Europe's biggest M-way project

The road, which will cross France from Bordeaux in the west to Lyon in the east, goes through the Bernand valley, where the toads, whose official name is bombina variegata, are found.

The valley is home to several other rare species, including the woodlark, northern harrier and the red-backed shrike, but it is the toad that has been adopted by environmentalists fighting to stop the 288km motorway, which is the most expensive ever built in France.

"The path taken by the motorway represents a great bloody gash through this region of great biological interest," said a spokesman for the Association for the Defence of the Valleys of Gand and Bernand, which is led in its crusade to stop the A89 motorway by Marie-Emilie Germain, 78, who was the first woman in her area to get a university degree in 1944.

"She is leading the fight for future generations," her son said. "The path [of the motorway] is an affront to her common sense."

The environmentalists have taken their case to court and a decision is expected later this month.

Although the Bernand valley is classified as a conservation area by the French authorities, its zoning, as a nature zone of ecological interest for its fauna and flora, offers little real protection under the law.

This has resulted in heavy criticism of France by the European Union for its failure to translate the Natura 2000 directive in favour of protected sites into sufficiently concrete terms.

Nevertheless, the French authorities are worried that the environmentalists could succeed in holding up construction of the final leg of the motorway for months, or even years, until a way can be found to protect the yellow-bellied toad.

They have good reason to worry. The preservation of the tiny hermit beetle recently held up construction of the A28 motorway, near Angers in western France, for more than five years after activists argued that the road threatened its habitat. Only when the trunks of the trees in which they lived were successfully moved far from the site of the road could the motorway be completed.

If the legal fight to have the route of the A89 changed fails, the toad's usual tactic of rolling on to its back to show its poisonous belly is unlikely to stop the bulldozers.

"The toad's only defence is to play dead by lying on its back and showing its coloured stomach, which contains irritant products," said one French naturalist. "In the animal world, a yellow stomach is a sign which never lies: if you bite, you are going to get a nasty surprise. There might occasionally be one bite, but never two."