In the afternoon of Saturday 25/09/2021 I saw a small grey and white duck (pictures at the bottom of this question post). It was small, about the size of a Little Grebe. I have a copy of RSPB What's that Bird?: The Simplest ID Guide Ever but cannot identify the duck I saw from any of the ducks therein, male or female. Perhaps it is a juvenile of one of those ducks?
Does anyone know? Any thoughts gratefully received.