The urban high-rise office building where I work has a problem with little birds flying into windows, not knowing anything is there. The birds crash into a window and the crash and the fall to the ground kills them. To fix this, building maintenance put up black silhouettes of birds on some of the windows - silhouettes of birds of prey like hawks - and this seems to scare the little birds away before they crash into the windows. I can’t say it works all the time but it seems to help.
There was a passageway between two buildings, with glass windows that had the same problem at that facility. They did the same thing, large black bird silhouettes. The passageways were about 15 feet wide, with glass windows on the sides about eight feet tall, and connected floors 2,3, and 4.
The hawks would attack the conference rooms in the facility, especially one particular one a corner.