Calif. Wine Country Clashes With Ecosystem

"Animals like bobcats, gray foxes and striped skunks were detected most often in wide corridors," Hilty said. "Native animals used wide corridors twice as much as narrow ones, and more than three times as much as denuded ones." Results were published in February in the journal Conservation Biology.

Sonoma County has a mandated vineyard stream setback of 25 to 100 feet on each side of a waterway, depending on its location. The widest setbacks are along the Russian River, home to the threatened coho salmon.

"With literally thousands of miles of streams here, we need to find a balance between vineyard expansion and riparian protection," said Greg Carr of the Sonoma County Permit and Resource Management Department.

A proposal under consideration by the Sonoma County Board of Supervisors would increase stream setbacks for non-agricultural development, such as housing, to 200 feet along the Russian River and to 100 feet on all other streams identifiable on a U.S. Geological Survey map. The required setbacks for agriculture, including vineyards, would be only about half as wide. In vineyards with a slope of more than 20 percent, and thus more likely to produce erosion, 100-foot stream setbacks would be mandated.

The wider setbacks being reviewed by the Board of Supervisors are about as wide as the "narrow" corridors in Hilty's and Merenlender's study, Hilty noted. "Even this setback size," she said, "is not enough. Large predators, for example, need extensive streamside territories in which to hunt."

"We have turned landscapes into obstacle courses, and that requires thinking differently about restoring connectivity," said biologist Thomas E. Lovejoy, president of the Heinz Center for Science, Economics and the Environment, a nonprofit policy institute in Washington, D.C. "If you make sure that streams have enough vegetation along their banks to control silt and other runoff from land, you can go a long way toward that connectivity."

Vineyard owners' reactions to the setback proposals have ranged from welcoming to quietly accepting to resistant.

At Gallo, Lyon did not respond directly to questions about the company's position. In March 2003, the company, one of the two largest land-owners in Sonoma County, reached a settlement with the county over complaints that vineyards at its Twin Valley Ranch had discharged sediments into waterways that flow into Porter Creek and then the Russian River. Gallo committed to more than half a million dollars in various mitigation projects.

Not far from Gallo land, as the bobcat roams, is Alexander Valley Vineyards, one of the places where Hilty placed her cameras.

Manager Mark Houser said, "Foxes, quail and even a mountain lion frequent Hoot Owl Creek, which runs through our property." While he, too, did not address the setback proposal directly, he said the vineyard's philosophy is that "while we're here to make a living by growing grapes, we're not here to scorch the earth in the process."