Hi Reuven,
Thanks for your input. I too did a little more searching on the net and yes, you are correct, it could very well be a Mallard x American Wigeon hybrid. The body colours fit the Eurasian Wigeon exactly according to my Sibley Guide (and that"s what I was going by) but many claim it to be an American Wigeon cross. Given the geographical location of the bird, an American hybrid does seem far more likely. Interesting.
Walter