Fond of their colorful feathers and soul-nourishing songs, many homeowners take special care to make their yards extra hospitable to birds. But even if you do nothing to court their company, birds may choose your gutters as the location for a long-term nest. It could be worse; compared with other pests, birds are relatively benign. They're not harmless, though. For one, their droppings can stain highly conspicuous parts of your home's exterior. For another, their nests can undermine, if not completely undo, the efficacy of your storm drainage system. Worse still, even if you make it a point to remove one bird's nest, you can't discount the possibility that another will simply take its place.