Even though these are big issues, the solutions are fairly obvious. Wetlands can be secured through a combination of new laws and easements that compensate landowners for protecting potholes. Similarly, disincentives can be provided that help secure native grasslands, along with incentive-based approaches like purchased grassland easements that benefit both ranchers and ducks. The ranking systems for CRP can be changed again to reflect priorities that were present in the 1985 Farm Bill, when millions of acres were first enrolled in the PPR. These changes will take commitment and far-sighted leadership, but at least the path is clear. Unfortunately, the potential solutions to other threats are more elusive.
For example, scientists have discovered that prairie pothole wetlands are growing old before their time. For decades, soil and wind erosion has deposited about a quarter of an inch of sediment per year into the average prairie pothole. Not surprisingly, the deposition is worse in wetlands surrounded by cropland, as opposed to grassland. So what's the big deal about a quarter-inch of dirt? For one, that's all it takes to severely depress aquatic invertebrates that live a part of their life cycle in the mud of prairie wetlands. These invertebrates are the food source for many ducks during the breeding season. Moreover, since the average prairie pothole is only a few feet deep, a deposition rate of a quarter-inch per year means a three-foot-deep wetland will be filled completely in less than 150 years. Many prairie potholes have been surrounded by cropland and therefore have been subject to sediment deposition since the early 1900s.
Another unexpected source of concern for PPR ducks is biotech crops. New varieties of soybeans and wheat are not only more drought tolerant, but many also have an engineered resistance to nonselective herbicides. This makes them capable of growing in sites that are now devoted to ranching. The problem is most acute in central South Dakota, where biotech crops and world demand are fueling the destruction of tens of thousands of acres of prime pintail breeding habitat. Soybean fields don't grow pintails. Certainly, it's a poignant reminder that new technology has the potential to put all natural habitats at risk. The conversion of native prairie could accelerate rapidly with the introduction of biotech wheat, which seems destined to be widely adopted by farmers. In the PPR, where wheat is king and farm profitability is front-page news, vigorous debate has surfaced among farmers as to whether biotech crops should be grown.
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