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Prairie potholes are not a sign of a road in need of repair, but rather shallow depressions created by the movement of glaciers during the last Ice Age that filled with water. They are among the most productive breeding habitat for waterfowl in North America.
This region is named "mixed grasslands" because it is the area between the moist tallgrass prairies in the east and drier shortgrass prairies to the south and west. One piece of the habitat, called the Cypress Uplands, is believed to have escaped being covered by the last glaciers. Found in Canada's Alberta and Saskatchewan provinces, this area on the lower slopes of the Rocky Mountains looks different from the surrounding grasslands. The region is dominated by lodgepole pines mixed with deciduous trees and wild lupine, rather than grasses.
The grasses that give this habitat its name include grama, little bluestem, needle-and-thread grass, and wheatgrass. These grasslands provide food for many herbivores and their predators, including pronghorn, black-tailed and white-tailed deer, short-horned lizards, western rattlesnakes, white-tailed jackrabbits, sage grouse, and coyotes. The majestic bison of the plains used to live here in large numbers before humans took them to the brink of extinction; they are now making a small comeback thanks to conservation efforts.
Virtually no large areas of intact mixed grassland habitat remain today, and nearly 80 percent of the area's wetlands have been destroyed or damaged, largely due to the conversion of the habitat to farmland. For more information on this ecoregion, go to the World Wildlife Fund Scientific Report. All text by World Wildlife Fund © 2001
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