A clever wolf repeatedly snuck into a Minnesota ranch. Biologists figured out its MO.

Voyageurs Wolf Project lead researcher Tom Gable uses rocks to shore up a hole near a gate in the perimeter fence at Wes Johnson's cattle ranch. (Anthony Souffle/The Minnesota Star Tribune) But last week, standing in the tall grass of the ranch as a dozen cows lazily grazed, Gable said he realizes how lucky it was that the one wolf in all of northern Minnesota most determined to get on the ranch happened to be a wolf that had a GPS collar around its neck. It was placed years before as part of the Voyageurs Wolf Project's research.

Gable likened it to a security firm hiring a hacker to find the flaws in its system.

"She showed us exactly where to find every weak spot we had," Gable said.

There were 192 calves born on the ranch this spring. On Nov. 11, Johnson counted 192 calves still grazing on his ranch.

"It's the first time nothing's disappeared," he said. "We never had none get sick and never lost any to wolves."

There have been no signs of wolves breaching the fence this year. No 04D. No other collared wolves. No paw prints, or scat.