barred owl vs bird of night

barred owl and bird of night both are nouns.

Word	Noun	Adjective	Verb	Adverb
barred owl	Yes	No	No	No
bird of night	Yes	No	No	No

As nouns, bird of night is a hypernym of barred owl; that is, bird of night is a word with a broader meaning than barred owl:

barred owl: large owl of eastern North America having its breast and abdomen streaked with brown
bird of night: nocturnal bird of prey with hawk-like beak and claws and large head with front-facing eyes

Other hypernyms of barred owl include bird of Minerva, hooter, owl.

barred owl (noun)	bird of night (noun)
large owl of eastern North America having its breast and abdomen streaked with brown	nocturnal bird of prey with hawk-like beak and claws and large head with front-facing eyes