side view of a male knob-billed duck also know as african comb duck

african agriculture animal asia background beak bill bird black blue blueblack china closeup colorful comb dabbling dark duck explore fauna field foraging glossy grass green grey head iridescent knob-billed knobbilled macro male meadow melanotos natural nature neck ornithology outdoor pond rainforest sarkidiornis side south species spot spots swamp tropical view waterfowl wetland wetlands wild wildlife wings