An immature male Scaly-sided Merganser (Mergus squamatus) standing on a rock beside a small pond in Southern England

The Scaly-sided Merganser or Chinese Merganser (Mergus squamatus) is a typical merganser (genus Mergus). It lives in temperate East Asia, breeding in the north and wintering in the south. The species is considered endangered by the IUCN. Its numbers declined in the 1960s and 1970s due to loss of primary forests in its limited range, particularly along the major rivers in Russian Far East.