Ключевые слова: adult, animal, aquatic, atra, beautiful, bird, birdwatching, black, cold, colony, colorful, common, coot, danube, dark, december, delta, eurasian, european, family, fauna, flock, foraging, formation, frost, frozen, fulica, group, habitat, ice, icy, lake, many, migration, migratory, natural, nature, ornithology, outdoor, peace, plumage, reflection, river, row, seasonal, together, water, wild, wildlife, winter,