Gadwall Duck (Anas Strepera) The Gadwall Duck is the world-famous dabbling duck and belongs from the Anatidae family. This Gadwall Duck has the same size like as Mallards Duck. Here in this article, you will see the Gadwall Duck Facts, identification, eggs information and photos. Similar Species American Wigeon Blue-winged Teal Green-winged Teal Mallard Gadwall