To keep sparrows out of nesting cavities or other sites, the openings should not be larger than ¾". Any sparrows found in nest boxes should be immediately removed. Openings greater than ¾"; around houses and other buildings should be screened off or blocked to prevent entrance. All outside structures such as air conditioners should be mounted with no open spaces between it and the structure. Exclusion of sparrows around bird feeders is difficult. However, do not scatter birdseed on the ground where they prefer to scavenge. Avoid cheap mixed bird seed that contains a large amount of filler grains, such as milo, millet or cracked corn. Concentrate on using sunflower seeds which are preferred by many songbirds, but not by house sparrows.