Climate change, conversion of native prairie to cropland and reduction of acreage enrolled in the USDA's Conservation Reserve Program (CRP) appear to be converging and impact substantially the numbers of wetland- and grassland-dependent wildlife in the country's prairie pothole region, according to the Wildlife Management Institute.

Scientists from the U.S. Geological Survey, St. Olaf College and the Universities of South Dakota State, Montana, Nevada and Idaho conducted an analysis of impacts of climate change on hydrology and vegetation in the prairie potholes. Results of their work are published in the current issue (Vol. 60, No. 2) of "Bioscience," and predict that, as climate change advances, the region will not be able to support historical levels of waterfowl and other wetland-dependent species due to significantly drier conditions. The results also project that wetlands in the region will be less full and the water that does collect in the wetland basins will remain for shorter periods.

These projections come on the heels of continuing, well-underway losses of native prairie and CRP-driven grassland habitat in the region. A recent University of Michigan study, funded and published by the National Wildlife Federation, notes that, while it is difficult to quantify the level of conversion of native prairie to cropland, "habitat loss in the form of sodbusting is significant in the study region" of North and South Dakota, Iowa and Minnesota.

The loss of acres enrolled in CRP, on the other hand, is well documented. As reported in the November 2009 ONB issue, "the Dakotas and Montana lost more than 960,000 acres of grassland habitat in 2007 and another 335,000 acres in 2008 as a result of expiration of CRP contracts. During the next three years, contracts on an additional 3.4 million acres will expire in this same area." Loss of CRP acreage is being driven in part by rules included in the 2008 Farm Bill. In early September 2007, there were 36.8 million acres enrolled in CRP. The 2008 Farm Bill included language that placed a cap of 32 million acres in the program by 2010.

In addition to nature and legislative mandates, economics and advances in technology are helping to advance losses of wetland and grassland habitats in the region. The ethanol boom has led to more demand for corn for conversion to biofuel, which, in turn has led to higher corn prices. Higher prices provide incentive for more corn to be planted. USDA statistics show that corn planting in the United States increased by nearly 12 million acres between 2005 and 2007. In addition, genetically modified crop varieties now can be used to produce economically viable yields on lands that formerly were unsuitable for crop production.

The merging of climate change, reduced acreage in CRP and the rush to biofuel production at the expense of uncultivated landscape does not bode well for the prairie pothole region's invaluable habitat for diverse and abundant wildlife. (pmr)