If you want to attract more birds to your yard, you can entice them with some empty eggshells! Rinse yours after breakfast, then you can sterilize them by baking on a cookie sheet in a 250° oven for about 10 minutes. Now crumble them, then add to your feeder or around the ground. The birds, most especially the females who have recently laid eggs, will come to nibble on this feast to boost their calcium.