A OMNIVORE they eat plants and bugs or insects
Cardinals are actually granivorous birds. Although they do eat some insects or fruit on occasion they do maily eat seeds.
Herbivores eat plant matter
Carnivores eat meat
Omnivore is a varied diet
Granivores eat grains seeds etc
Piscivores eat maily fish.
I know they eat seeds, a herbivore, but i would think they would also east some bug, insect and etc. For protein.
My guess would be that they are Herbivores because they eat seed and things like that.