genus Calidris vs bird genus

genus Calidris and bird genus both are nouns.

Word	Noun	Adjective	Verb	Adverb
genus Calidris	Yes	No	No	No
bird genus	Yes	No	No	No

As nouns, bird genus is a hypernym of genus Calidris; that is, bird genus is a word with a broader meaning than genus Calidris:

genus Calidris: a genus of Scolopacidae, containing the knots and the surfbirds (Calidris)
bird genus: a genus of birds

genus Calidris (noun)	bird genus (noun)
a genus of Scolopacidae, containing the knots and the surfbirds (Calidris)	a genus of birds