May try putting up a mirror close by. That way it may bother the mirror and not the window. Had this problem with my car. Bird would fight the mirror and crap and bleed all over the car. Covered mirror and it moved to the other side. Wife said send that bird to see his maker.

61 acre water shed lake. bass, channel cat, black crappie, wiper, walleye, redear sunfish, blue catfish and bluegill. To many bullhead and common carp
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