Many birds prefer sunflower. Some prefer millet. A few prefer peanuts. Sparrows, blackbirds, doves and juncos will eat the other grains used in pre-made mixes: corn, milo, red millet, oats, wheat and canary seed. Birds will also kick out artificial “berry” pellets, processed seed flavored and colored to look like real fruit.
Black oil sunflower is the hands-down favorite of all the birds that visit tube and house feeders. Birds who visit platform feeders (doves and sparrows) favor white proso millet. Ducks, geese and quail will eat corn. Many cereal grains (corn, milo, oats, canary, wheat, rape, flax and buckwheat) in mixed bird seeds are NOT favorites of birds that visit tube feeders.
The most effective way to attract the largest variety of birds to your yard is to put out separate feeders for each food:
a starling-resistant suet feeder
a house feeder for sunflower
a bluebird feeder
a wire mesh cage feeder for peanut
a nectar feeder
a tube feeder for thistle