bird feed vs bird food

bird feed and bird food both are nouns.

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

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

Other synonyms of bird feed include birdseed.

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