No need for eye test, Gary - it is indeed a Hooded Merganser, but in an odd plumage. Apparently up to five seen around that area recently - all from the collection at Spaxton.

You’re right cliff, having a funny five minutes- will book eye test in the morning!

don’t really have the bill shape for merganser (sawbill) does look more like Goldeneye but still the beak is not quite right! perhaps some sort of hybrid or exotic escape? #baffled

I think that’s a hooded merganser. If l remember rightly one escaped from a collection near Bridgwater ( I’m sure someone else will recall the details).
By the way , nice photos

There was a duck on it’s own at Ashford reservoir near Cannington today, but I’m not sure what it was!
  It was a diving duck and looked like a female, I thought maybe a Goldeneye, but ducks are not my strong point!

Pics on my blog, if anyone can help!

http://carlbovisnaturephotography.blogspot.co.uk/2016/11/long-tailed-tits-robins-goldcrests-and.html