whistler vs Bucephela clangula

whistler and Bucephela clangula both are nouns.

Word	Noun	Adjective	Verb	Adverb
whistler	Yes	No	No	No
Bucephela clangula	Yes	No	No	No

As nouns, whistler and Bucephela clangula are synonyms defined as:

whistler and Bucephela clangula: large-headed swift-flying diving duck of Arctic regions

Other synonyms of whistler include goldeneye.

whistler (noun)	Bucephela clangula (noun)
Australian and southeastern Asian birds with a melodious whistling call	large-headed swift-flying diving duck of Arctic regions
large-headed swift-flying diving duck of Arctic regions
large North American mountain marmot
someone who makes a loud high sound