That's the solution rangers in Quebec's Mont Tremblant National Park are trying after having to kill three wolves showing signs of becoming too comfortable around people last year, The Gazette newspaper in Montreal reported Monday. The park has about three dozen wolves.

The rangers, who blame campers who feed the wolves, put up two miles of fencing around 300 campsites on Monroe Lake a month ago. The fence consists of a single strand of low-strung nylon cord with wide strips of red cloth every yard or so. It's a centuries-old European trick that some U.S. ranchers use to protect their herds, but it's the first time it's been tried in a national, provincial or state park in North America, said Hugues Tennier, Mont Tremblant's chief conservation officer.

"Why this curtain works, we don't know," he said, though some research indicates it may have something to do with the color, an effect that may be only temporary.

So far, so good: There have been no reports of wolf sightings inside the perimeter.

Previous efforts to shoo away the wolves included sounding foghorns and "bear bangers," a small gun that fires a shell that makes gunfire noises, The Gazette said.