FOIX, France (AFP) - Thousands of ranchers and farmers concerned about their livestock demonstrated in southwestern France on Saturday against plans to introduce a group of wild bears as well measures to protect wolves and vultures.

Some demonstrators dumped sheep carcasses and manure in front of the local town hall to protest against the "re-wilding" of the mountains near Foix on the edge of the French Pyrenees, which they say is affecting their livelihoods.

Police said 2,500 protesters took to the streets although organisers said the figure was higher, at 4,000, with many protesters bringing their livestock and tractors with them for a go-slow around the town.

Ranchers and farmers are angry at what they call the "uncontrolled expansion" in the number of wolves across the country and a plan to introduce a dozen wild bears in the region. They are also concerned about the prevalence of the griffon vulture, which they have accused of attacking livestock.

The protest was called by the FDSEA agricultural union, a young farmers union and a group representing local hunters who are critical of the restraints put on them by the animal protection measures.

Protesters carried posters that read "stop the massacre", "hands off my mountain", and "wolves, vultures, bears: Stop".

France's Environment Minister Segolene Royal stepped into the row on Saturday, saying that attacks by wolves had become too frequent.

"The damage to herders has become too great," she said in a statement, with figures showing more than 6,000 livestock were killed by wolves last year.

"The distress of the farmers and their families should be taken more strongly into account," she said.

The animals were hunted almost to extinction in France in the 1930s, but crossed back into the country from Italy in the 1990s. They are now protected and number around 300.

About a dozen bears have been introduced to the Pyrenees region in the last decade, a programme strongly opposed by cattle and sheep farmers.

The latest tensions involve the griffon vulture, which usually feed on dead or weak animals, but which farmers say have changed their habits and are also now attacking livestock.

"That is forcing farmers to constantly keep an eye on their animals, which cannot be practical," Francois Toulis, head of the chamber of agriculture in the Pyrenees region of Ariege, told AFP.

Wildlife organisations deny claims that the bird has become a more active predator, and criticised a protest by "those who say they are defenders of rural life."