Green-winged Teal

Pretty regulalry recently I've been scanning Coot Loch when I pass it looking for an American duck that has been there on and off this winter.
This was not what I was looking for but is still an American duck - their variety of our Common Teal. 
It used to be ocnsidered a subspecies but was split to full species status several years ago. Not a difficult one to identify with the vertical go faster stripe rather then the horizontal one visible here in the Common Teal.