Mergus merganser; the Goosander is - like the read-breasted merganser, also a fish-eating duck. Mergansers & Goosanders too have long beaks with a sharp hook, adapted to catch small fish. The main food source is Sticklebacks. They can be found on Iceland along the coasts and lakes. They are though less common and in my experience much quicker startled than the the red-breasted merganser. I saw a few couples along the Laxá river between Mývatn and the hydro-electric plant between Mývatn and Húsavik. For differences between both merganser species see the page of the red-breasted merganser. Both Mergansers & Goosanders stay in small numbers on Iceland during the winter where waters don't freeze but most birds leave southwards.