We had a similar problem when we owned our house trailer in upstate NY with an oriole (sp?) It kept landing on my dark blue car and looking at himself in the mirror. I covered the mirrors with grocery sacks, then he would use the reflection in the window. I thought if I tied some feathers around the mirror area he would think another bird was there and leave. Well it worked, a neighbors cat seen the feathers and snatched the bird.....
. I hated to see that happen !
The bird droppings were actually staining the side of my car. Poor bird!