I have read that Mandarin and Wood ducks are the only ducks that have silver-white on the leading edge of their flight feathers. These ducks are found in southeast Russia, China, Japan, and Korea. They were introduced into Britain and exported to many other countries. The largest populations are in Japan and Britain. Ducks found in North America are usually escapees from collections or feral ducks in small numbers. There is a small colony of Mandarin Ducks in northern California. This couple lives at the Minnesota Zoo. I thought about cropping the hen out of the image to leave only the drake, but I didn't want to break up the couple :)