Rare ducks

I saw some unusual ducks at Colwick Country Park last saturday. Here are some photos of them. At the bottom, a Mandarin duck is to the right of a female mallard. Mandarin ducks are not native to Britain, but have established a "wild" breeding population in parts of the country. I had never seen one in the "wild" before. Several ducks can be seen in the top photo. The unusual ducks are sat next to each other to the right of the centre of the photo, underneath a large branch. Guesses as to their identification in the comments, please!! Or click here. There was a male and a female; it was the first time I had seen a male, which is particularly attractive.