We usually have problems identifying Sandpipers, especially when they’re flying. Our best guess as to the ones in the images here – based on size, plumage, and their being in our field pond – is that they’re Pectoral Sandpipers.
But these images were taken in August, when Pectorals (if that's what these are) are supposed to have already migrated to Canada, Alaska, and the Arctic.
Anyway, we have an excuse to point out that Pectoral Sandpipers get their name from the males’ puffing out their chests (pectoral muscles) to impress the females.
It just occurs to us that we have fewer problems identifying Pectoral Humans than we do Sandpipers. (Brooklin, Maine)