lesser scaup duck vs lesser scaup

lesser scaup duck and lesser scaup both are nouns.

Word	Noun	Adjective	Verb	Adverb
lesser scaup duck	Yes	No	No	No
lesser scaup	Yes	No	No	No

As nouns, lesser scaup duck and lesser scaup are synonyms defined as:

lesser scaup duck and lesser scaup: common scaup of North America; males have purplish heads

Other synonyms of lesser scaup duck include Aythya affinis, lake duck.

lesser scaup duck (noun)	lesser scaup (noun)
common scaup of North America; males have purplish heads	common scaup of North America; males have purplish heads