The region, filled with millions of glacially formed wetlands, includes parts of western Iowa and Minnesota, the central and eastern Dakotas and parts of Manitoba, Saskatchewan and Alberta.
Scientists at South Dakota State University examined 20th century records starting in 1906 for 18 Prairie Pothole Region weather stations.
The records showed a widespread trend toward warmer minimum temperatures, especially in the Canadian prairies, where some stations showed increases of more than 6 degrees Fahrenheit, wetland ecologist W. Carter Johnson said in a release Monday.
Much of the region has been turned into farmland and the best remaining duck nesting grounds are in the parts of the region where the effects of climate change are projected to be the most severe, he said.
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