I was just down on the river that runs through my place (Arkansas river, south-central Colorado mountains) and saw a little bird that was a golden-green, pecking around the mud at water's edge. The closest I could come in my bird book was a Wilson's Warbler. However, the golden stripe over the eye wrapped all the way around the head, under the dark dome, seeming to be even more "bright" around the back of the head. I could not see the underside because I was above, looking down. The back looked more uniform in color than the book makes out. And the bird looked a little more fleet and lean than the book.