Spot the difference

It is that time of year when birders sift through flock s of Golden Plover looking for variants on the theme. Normally one finds a juvenile bird that looks marginally different. This adult American golden Plover (different species nowadays) however made life easy. They lose their summer plumage on the wintering grounds as opposed to the European Golden Plover that does so on the breeding grounds making identification much easier.
PS gloomy light so apologies for the grainy nature of the shot.