There are three species of swans in North America. The Trumpeter swan and the Tundra swan are indigenous, while the
Mute swan is a Eurasian species that has been introduced and now breeds in the wild in some areas. Brought in from Europe as an ornamental addition to parks and estates, the Mute Swan has established itself in a feral state in some parts of North America, mainly in the northeast. Mute swans are the most common swans in the wild, in parks or on country estates in their native range. They live in well-sheltered bays, open marshes, lakes, and ponds. In winter, they are more common on marine waters. They are best distinguished from North American swans by the knob at the base of the upper bill, and the color of the bill itself, which is orange, with the tip and base colored black. —
animaldiversity.org;
trumpeterswansociety.org