Bird Collisions with Towers and Buildings. For Birds Scientists estimate that between four and ten million birds collide with man-made towers each year.
Most deaths occur during migration in inclement weather.
The collisions involve primarily night-migrating songbirds such as warblers, thrushes, vireos, tanagers, cuckoos, sparrows, etc. Tall towers are necessary to provide cellular phone service and wireless Internet connections. New towers are being constructed at an alarming rate. Today, there are over 50,000 towers over 200 feet tall in the United States. Tower warning lights that blink white or red seem to be less effective than white strobe lights.