bird food vs bird feed

bird food and bird feed both are nouns.

Word	Noun	Adjective	Verb	Adverb
bird food	Yes	No	No	No
bird feed	Yes	No	No	No

As nouns, bird food and bird feed are synonyms defined as:

Other synonyms of bird food include birdseed.

bird food (noun)	bird feed (noun)
food given to birds; usually mixed seeds	food given to birds; usually mixed seeds