I only use Black Oil Sunflower seeds, Striped sunflower seeds, Safflower seeds (cardinals), and Black Niger seeds (finches). Mourning doves like grain seeds but they're just as happy pecking around in the lawn. Mockingbirds will eat from a feeder if there re dried berries in them but not often. Robins typically won't eat at the feeder, I think, regardless of what you put in it. They are everywhere in the garden looking for worms.
My feeder visitors are mostly cardinals, chickadees, nuthatches, titmouses, downy and red bellied woodpeckers, bluejays, house finches, goldfinches, as well a the not so welcome house sparrows, grackles, and squirrels. Seasonal visitors include redpolls and pine siskins.
When I have the energy to keep up with changing the nectar, I also put out one or more hummingbird feeder.
Other birds that don't like the feeder so much also visit my garden for insects, berries, etc. Kinglets in early spring and late fall, Juncos in winter, catbirds in the summer, flickers, bluebirds, warblers, etc.
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