Thus, natural cavities are sparsely distributed, particularly in young forests, in areas with low woodpecker populations, and in areas where dead trees have been cut down. In these types of areas, cavity_nesting birds often have difficulty finding nesting and roosting sites and will readily use suitable birdhouses. Properly constructed birdhouses provide nesting and roosting birds the same protection as natural cavities in trees. This includes protection from wind, rain, cold, and nest predators (red squirrels, weasels, ravens, crows, jays, etc.).
While it is okay to paint the outside of a bird house, do not paint the interior surfaces or the inner rim of the entrance hole. Furthermore, use only environmentally safe paints, stains or varnishes on the outside and avoid any lead_based paints that can poison birds from fumes or ingestion. Choose a bird house design with the proper interior dimensions for the desired residents: Too small of a house may cause growing birds to smother, while too large of a house will not be attractive to nesting parents. Smaller birds could also become too chilled in a larger house if they are not huddled together when needed.