How are ducks adapted to their habitat?

1) ducks are waterfowl, swim and dive well; have a swimming membrane between the toes;
2) legs are short, set far back; on land move slowly and awkwardly;
3) the plumage is dense, protects from getting wet; there are air bubbles in the thinnest cavities of feathers;
4) feathers are lubricated with the secret of the coccygeal gland to protect from water, preserve their elasticity