Here’s an interesting idea! Protect Wild Birds From Striking Windows with WindowAlert Decals. The decals contain a component which brilliantly reflects ultraviolet sunlight. This ultraviolet light is invisible to humans, but glows like a stoplight for birds. Birds have vision that is up to 12 times better than that of humans. WindowAlert decals help birds see windows and avoid striking the glass. They are several designs to choose from and each pack contains 4 Decals for $6.45. And what I like is that shipping is only $0.50, making them $6.95 shipped.