Mergus serrator; the red-breasted merganser is a fish-eating duck. Mergansers & Goosanders 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. Goosanders (Mergus merganser) are not very common on Iceland but are breeding birds. The red-breasted merganser is quite common, though. The drakes are easily distinguishable: male goosanders have white breasts , white bellies and no crest while r.br.mergansers have reddish marbled breasts, greyish breasts and a crest. Females are more difficult to tell but goosander females have a strict line between the red color of the head and the white color of the breast. In the merganser females this is blurred. Apart from that females only differ in size (62 cm goosander vs. 55 cm merganser). Both Mergansers & Goosanders stay in small numbers on Iceland during the winter where waters don't freeze but most birds leave southwards.