I just wanted to add to this posting.
Nick Komar and I were birding at the north end of Boyd Lake State Park in Larimer County this evening when I spotted a male Piping Plover feeding in the mud flats. I showed the bird to Nick, but it flew off before we were able to photograph it. Nick relocated it after sunset on the west side of the lake below the northmost parking lot in the park. We had distant looks at the bird from across the lake, but the light had gone by the time we drove around to the west side of the lake to try and get a better look a the bird. given north winds and predicted rain, it may stay the night.
The bird was a nice adult male with a broad black chest band. I didn't see any color bands on its legs.
Other species present included two Black-bellied Plovers in alternate plumage, five Semi-palmated Plovers, a Long-billed Curlew, two Bonaparte's gulls and two Cassin's Kingbirds.
Walter Wehtje
Fort Collins, CO