Whooper Swan

Whooper swans occupy the boreal zone of Eurasia and many nearby islands. Breeding populations occur from Iceland and the British Isles eastward, while wintering birds travel to countries including China, Korea, Japan, and India. They nest beside freshwater lakes, pools, shallow rivers, marshes, bogs, and swamps, particularly where emergent plants shelter nests and cygnets. Nonbreeding birds also use protected estuaries, lagoons, and shallow bays. Adults measure 1.4 to 1.65 meters long, span 2.05 to 2.75 meters, and weigh 7.4 to 15.5 kilograms. (Animal Diversity Web)

Adult whooper swans feed chiefly on aquatic plants, roots, and tubers, digging into mud with their webbed feet before reaching underwater. They also graze on land and in tidal habitats. Growing cygnets consume insects and other invertebrates for additional protein, and parents may stir the water to expose food. Whooper swans form lifelong monogamous pairs and defend breeding territories vigorously. They breed once annually, beginning in late April or early May. Clutches contain one to eight eggs, with incubation lasting 30 to 32 days. (Animal Diversity Web)