We only discovered this Purple sandpiper after we had seen a fledgeling in the grass. "Where there is a kid there is a mother," I said. And very well, a parent soon appeared, i.e. the individual in this picture. But that it is a 'mother', just because it is a caring parent, is in this case doubtful, as among Purple sandpipers, the male it is usually the one that sits through most of the incubation and then takes care of the nestlings. So my qualified guess is that the individual in this picture is in fact the dad...