Black-oil sunflower seed: preferred by the widest variety of species. Chickadees, Titmice, Cardinals, and Nuthatches are among the popular feeder birds that favor black-oil sunflower seeds.
White millet: Many ground feeding species, such as Juncos and Sparrows, are attracted to white millet.
Red milo: Some western species, including Jays flock to red milo.
Cracked corn: By scattering cracked corn over the ground, you’ll invite Doves and Pigeons to your feeding station.
Mixed seed: This is best sprinkled on the ground or onto platform feeders. Mixed seed typically contains high quantities of millet, preferred by ground-feeding birds: many feeder birds will not take millet. Likewise, ground-feeding birds that favor millet will not have access to it if it’s in a feeder.
Nyjer: (Niger) Also known as thistle seed, this will attract small finches such as Goldfinches, Siskins, and Redpolls. There are feeders specifically designed for thistle seed.
Safflower: Although this seed is typically more that sunflower, it is not proven to be more preferred, but some reports claim that squirrels dislike it.
Sugar water: Hummingbirds are attracted to sugar water. Prepare this by mixing four parts water to one part sugar and bringing to a boil. Allow this to cool before pouring it into your hummingbird feeder.
Suet: Woodpeckers, Chickadees, Titmice, and Nuthatches all enjoy suet. You can hang this in a mesh bag, but it won’t be as protected from raccoons that might help themselves. You may wish to consider using a sturdy suet feeder.
Fruits: Raisins, bananas, currants, and sliced apples may attract Mockingbirds, Robins, Bluebirds, and Waxwings. Oranges are a favorite with Orioles.
Courtesy of Cornell Lab of Ornithology