Trumpeter Swans are much less numerous and widespread than Tundra Swans. Trumpeter Swans are larger and their bills are always all-black; most Tundra Swans have a yellow spot at the bill base, although this can be hard to pick out at distance. The border between the bill and the white feathers of the head has a different shape in the two species: Trumpeter has a more smooth line between mouth and eye, and the margin comes to a point on the forehead. Mute Swans have a black knob at the base of their orange bill, and they typically hold their necks in a graceful S-curve, not straight as in Tundra Swan. Snow Geese are much smaller, with shorter necks, mostly pink bills, and black wingtips that are prominent in flight and usually also visible when the wings are folded.
The Eurasian subspecies of the Tundra Swan is known as Bewick’s Swan. It is slightly smaller than the North American Tundra Swan and has more yellow on the bill. Individuals are occasionally found in western North America, usually in flocks of Tundra Swans.
Find This Bird
Unless you’re in the arctic, don’t look for Tundra Swans in the summer. Instead, look for them on large bodies of water, particularly estuaries and protected coastal waters, during migration and in winter. You may also see flocks of these large white birds in agricultural fields where they are feeding on spilled or unharvested grains. Look for their distinctive straight-necked posture, as well as their characteristic large flocks, to separate them from Mute Swans.