European method might effectively keep livestock safe
Here´s the problem: You´ve got a pasture full of livestock, you´ve got hungry wolves nearby, and you want to prevent the wolves from killing your animals. How do you do it?
You do it by messing with their minds.
That´s what the federal government and a private animal-conservation organization did last summer in east-central Idaho a few miles from the Montana border. They created a “psychological barrier” between wolves and cattle, and it kept the cattle safe for most of the summer.
The barrier was a length of twine, from which hung harmless strips of plastic or cloth, known as “fladry.” Wolves fear it.
The Idaho experiment, and others in that state and Montana, followed research under way in Canada. But the technology isn´t new. People have used it for hundreds of years.
“It all started in Europe,” said Marco Musiani, an Italian who is a graduate student at the University of Calgary in Alberta. “I did my Master´s thesis in Poland, and I noticed hunters using this technique to hunt wolves. Even the word is Polish.”
Hunters strung hundreds of yards of fladry in the shape of a “V.” Working from the wide end, they drove entire packs of wolves into the “V” and killed them at the narrow end, where the animals were reluctant to cross the cloth barrier.
In Idaho and elsewhere in North America, it is seen not as a means to kill wolves, but to protect them; to keep them from killing livestock — a behavior that often results in their own death sentence.
Musiani, a biologist who is studying for his doctorate in environmental design, came up with the idea of using fladry to keep wolves out rather than in.
“But we needed to do some experiments,” he said, “because we didn´t know if it would work or what the optimal design was.”
In a two-month experiment in Alberta, workers strung fladry around a 160-acre pasture.
“During the experiment, they had no problems,” he said, “but wolves were approaching the area. On 17 occasions, they approached the area and they turned back.
“After two months, we had to suspend the experiment,” he said. “After we removed the fladry, the wolves got back to the area and killed livestock again.”
In 1995, starting with four gray wolves, the U.S. Fish and Wildlife Service began reintroducing them to Idaho, which was — like Washington — a part of their natural range from which cattlemen and others had extirpated them. The effort was controversial, and still is. Many agriculturists and sportsmen complain that wolves kill too much livestock and too much game. Biologists estimate Idaho now contains eight “breeding pairs,” or extended-family packs.
In the Idaho experiment last summer, with Musiani´s collaboration, workers strung fladry around more than nine miles of cattle ranch near Salmon.
“We think it´s probably the largest (fladry) experiment in the world,” said Suzanne Laverty Stone of Boise, western field representative for Defenders of Wildlife. The material enclosed an entire ranch.
It kept the wolves at bay for 61 days.
The study was a cooperative effort of Defenders of Wildlife, the Fish and Wildlife Service and that agency´s Wildlife Services branch. The Fish and Wildlife Service purchased the material, Wildlife Services helped oversee the project and provided equipment, and Defenders of Wildlife furnished volunteers to install the material, said Carter Niemeyer, Idaho wolf recovery coordinator for the Fish and Wildlife Service in Boise.
Fladry is heavy-duty twine on which is located, about every 18 inches, a strip of flagging some three inches wide and 20 inches long. Workers install it so the bottom of each ribbon hangs just a few inches off the ground, creating a visual barrier about 28 inches high.
“It gives the appearance — from a human perspective, anyway — of being a barrier,” Niemeyer said. “I believe it´s a psychological barrier that causes wolves to hesitate and avoid passing by it or through it or across it.”
In the Idaho experiment, workers strung the fladry on an existing barbed-wire fence, to save labor and money. Ironically, the cattle pastured behind the fence — those the fladry was intended to protect — destroyed some of it.
“Some of the fladry got wrapped around the barbed wire,” said Musiani, “and the cattle were pulling away some of the fladry and even ingesting some flags.”
And, while the cattle had no apparent fear of the material, that wasn´t so for the wolves.
About two months passed before they crossed the line. Besides the presence of cattle, a motive for crossing may have been their den site, which was within the protected perimeter, Carter said. The area the workers had cordoned off “was in the center of their home territory.”
Even then, the wolves were reluctant to cross a second time, to go out, even after officials called in a helicopter to pursue them.
“They tried to drive the wolves across it, and the wolves refused to cross,” said Stone. “They actually ran back under the helicopter instead of crossing it again.”
Still, the single crossing showed that fladry is not infallible. Stone calls it “a somewhat reliable, temporary tool, which is what we were looking for.
“Every predation situation is different from every other one,” she said.
“If, say, we have a calving operation and the wolves come in to that, the cows really are the most vulnerable (then). So, if we can use the fladry temporarily, we can buy ourselves a month.”
Researchers hope, she said, that stockmen “can possibly use it temporarily time after time with the same wolves, and they may not habituate. It´s a very inexpensive tool.”