To prevent the spread of some avian diseases, food should not be spread on the ground, and feeders should be cleaned and disinfected regularly. Other Attractions for Birds.Birds do not have teeth; instead, they grind food in their gizzards. Birds eat small pieces of sand and gravel, or "grit" to aid the grinding process. In winter, when the ground is covered by snow, suitable grit may be hard to find. You can supply grit to birds at the feeder in the form of crushed eggshells, coarse sand, or from boxes of grit that are sold at variety and pet stores.
Most birds that can be attracted to feeders are insect or seed eaters. Insect_eating species, such as chickadees and woodpeckers, are attracted by animal fats or "suet." This can be obtained from the grocery store or trimmed from beef, pork, moose, caribou, or other wild meat. Fats that have a low water content are best in areas with severe cold, because they freeze at lower temperatures. Peanut butter, another fat, also attracts birds to feeders. Its sticky consistency occasionally causes problems for birds, so it should be mixed with melted animal fat and cornmeal or rolled oats. That expensive peanut butter will last longer if it is mixed with other ingredients, anyway.