Ключевые слова: anas, bif, bifs, birds, common, coverts, crecca, dress, ducks, eurasian, fast, feather, feathering, feathers, flight, fly, flying, gray, grey, male, pace, plumage, prompt, promptness, quick, quickness, rapid, rapidity, rate, speed, spreaded, stretched, swiftness, teal, teals, velocity, wild, wings, winter,