Crush them into small bits and scatter in an open spot, such as a driveway, sidewalk, deck, or platform feeder. Watch as all kinds of birds stop by for a nibble. At our farm, martins, barn and tree swallows, chipping and song sparrows, bluebirds, robins, eastern towhees, and Carolina chickadees have eaten the eggshell bits we offer. Offering fruit and nectar. Almost any kind of fruit you put out for the birds will be eaten by some species.
Old standbys are oranges, grapefruits, melons, grapes, and apples.
Use your imagination and see what your birds prefer. We spike the fruits onto nails driven into feeder posts and snags all around our yard. For shy species, such as orioles and tanagers, we place a few oranges around the edges of our yard near spots these birds already frequent. Nectar is not just for hummingbirds anymore. More than 50 species have been recorded consuming nectar from feeding stations.