registered vs fauna

registered is not a noun while fauna is a noun.

Word	Noun	Adjective	Verb	Adverb
registered	No	Yes	No	No
fauna	Yes	No	No	No

registered (noun)	fauna (noun)
	a living organism characterized by voluntary movement
	all the animal life in a particular region or period

registered (adjective)	fauna (adjective)
listed or recorded officially
(of animals) officially recorded with or certified by a recognized breed association; especially in a stud book
(of a boat or vessel) furnished with necessary official documents specifying ownership etc