Can anyone tell me whether this is a leucistic Mallard or a Mallard cross? Or if neither, what is it?
Looks like a farmyard duck which may have a bit of Mallard in its genes. Most of our domestic ducks are probably derived from wild Mallard in times past and often those genes show through. I used to visit country shows a lot and it was interesting to see the many Mallard related species on show.
Pete
Birding is for everyone no matter how good or bad we are at it,enjoy it while you can