Sunset lights up the water and sky at Necedah National Wildlife Refuge in Wisconsin. The refuge, known to early homesteaders as the Great Wisconsin Swamp, provides important habitat for endangered species like the Karner blue butterfly and whooping crane. Of the experience, photographer Darlene Martin says: “The sanctuary is spectacular and surprisingly large. It was a beautiful spring evening, and the brilliance of the sunset was quite unexpected.” Photo courtesy of Darlene Martin. Posted on Tumblr by the US Department of the Interior, 5/13/16.