hen harrier vs northern harrier

hen harrier and northern harrier both are nouns.

Word	Noun	Adjective	Verb	Adverb
hen harrier	Yes	No	No	No
northern harrier	Yes	No	No	No

As nouns, hen harrier and northern harrier are synonyms defined as:

hen harrier and northern harrier: common harrier of North America and Europe; nests in marshes and open land

Other synonyms of hen harrier include Circus cyaneus, marsh hawk.

hen harrier (noun)	northern harrier (noun)
common harrier of North America and Europe; nests in marshes and open land	common harrier of North America and Europe; nests in marshes and open land