This looks very much like a Bahama Pintail to me, as illustrated by a painting in my aged Collins Pocket Guide to British Birds (1971 reprint, plate 49!)
On Sunday last Judith and I decided to go to Slimbridge, the Wetlands and Wildfowl Trust Centre on the Severn Estuary north of Bristol. I got "inspired" with my camera, and these are some of the better results.
The sign for Fordwich, Kent, where my grandfather lived at the time of the 1891 Census. Miles inland, it was nevertheless the original port for Canterbury, and ships sailed up the Stour to unload here - hence the Cinque Port status