"Quivira National Wildlife Refuge (NWR) is located in south-central Kansas within the transition zone of the Great Plains. In this zone, the relatively lush vegetation of the eastern prairie blends with the more arid grasslands of the western prairie. The blend of varied plant communities and the presence of the Big and Little Salt Marshes, major water features on the Refuge, attract birds common to both eastern and western North America. Over 300 species of birds have been observed in the marshes, grasslands, farmlands, and low sandhills of Quivira NWR."