Trumpeter swan which is apparent even when the swan is not standing or swimming upright) and larger, wedge-shaped bill as compared to the tundra swan. Trumpeter swans have similar calls to whooper swans and Bewick's swans. They are loud and somewhat musical creatures, with their cry sounding similar to a trumpet, which gave the bird its name. Beginning in 1968, repeated in 1975, and then conducted at 5-year intervals, a cooperative pan-continental survey of trumpeter swans was last conducted in 2015. The survey assesses trumpeter swan abundance and productivity throughout the entire breeding ranges of the three recognized North American populations: the
Pale-winged trumpeter Pale-winged trumpeter The pale-winged trumpeter ("Psophia leucoptera"), also known as the white-winged trumpeter, is a species of bird in the family Psophiidae. It is found in the southwestern Amazon rainforest of Brazil, northern Bolivia, and eastern Peru. It has two subspecies: The widespread nominate has a white rump and is found south of the Amazon River and west of the Madeira River, while "ochroptera" has a yellowish rump and is found between the Amazon River and the lower Rio Negro. Genetic evidence suggests the closest relative of "ochroptera" is the grey-winged trumpeter, leading some to treat it as a separate