Waterfowl--birds of the duck family--have webbed feet suitable for swimming and diving, and are mainly active in the deeper waters of rivers and lakes. Inside their broad flat bills they have a comb-like strainer with which they can filter plant material and insects out of the water, while the water's edge is where they sun themselves and roost.
「雁鴨科」擁有一對適合游泳、潛水的腳蹼，多活動在較深水的河流、湖泊，它們的扁嘴內有柵狀篩網，可以過濾水中的植物和昆蟲，水陸交界地帶則是它們曬太陽、休息的地方。