Common Merganser Mergus merganser (Goosander)

In North America this species is usually known as Common Merganser but in Europe it's much better known as Goosander. The two continents host different recognisable subspecies, so these are treated separately here. There is also a third subspecies in east Asia, Mergus merganser orientalis (I presume comatus as given in, for example, Reeber's Wildfowl book is a synonym of orientalis).

Goosander Mergus merganser merganser

American Common Merganser Mergus merganser americanus