Environmentalist: The complex ecosystem of the North American prairie has largely been destroyed to produce cattle feed  But the prairie ecosystem once supported 30 to 70 million bison, whereas North American agriculture now supports about 50 million cattle
Since bison yield as much meat as cattle, and the natural prairie required neither pesticides, machinery, nor government subsidies, returning as much land as possible to an uncultivated state could restore biodiversity without a major decrease in meat production
Preservation of the remaining North American bison would be a sensible policy.