I photographed this presumable Tundra Swan (yellow spot on bill) in Toronto the other day. However, the bird also seems to have some characteristics of a Trumpeter. What are your opinions? Thanks in advance!
Tundra for me, too. Trumpeter should never show a yellow loral spot, so that is the biggest mark here. Often the most consistent field mark is seen when the bird is head-on, in which the border where the bill meets the face is V-shaped in Trumpeter but roundly U-shaped in Tundra.