parula warbler vs northern parula

parula warbler and northern parula both are nouns.

Word	Noun	Adjective	Verb	Adverb
parula warbler	Yes	No	No	No
northern parula	Yes	No	No	No

As nouns, parula warbler and northern parula are synonyms defined as:

parula warbler and northern parula: small grey-blue wood warbler with yellow throat and breast; of eastern North America

Other synonyms of parula warbler include Parula americana.

parula warbler (noun)	northern parula (noun)
small grey-blue wood warbler with yellow throat and breast; of eastern North America	small grey-blue wood warbler with yellow throat and breast; of eastern North America