We have these large plate glass windows, and no matter what, the birds see the reflection of the woods and head right for them. THUNK! We here that sound several times during the year, especially in the spring, and when we look on the deck we sometimes see a stunned bird on the deck, just sitting there and wondering, "Wha happened?" This Indigo Bunting recovered after a few minutes and flew off. The secret for the bird is to wake up and leave before Niko finds them. Most do. Some don't.