Ribbon.
Older friend of mine has a 3' piece of ribbon tacked to his house (same color as his house), and I asked what gives? Told me that was an old trick used to scare off woodpeckers. Tack it up just over the spot, so it swings in the wind across the area they peck at. He showed me a couple of places that he had done so.
So, when I had the same issue, I tacked up ribbon just over the spot, sure enough seemed to work for me. Not sure why, but they don't like it.
I would guess that the silver mylar tape previously mentioned may do the same thing.
Yup, exactly the same thing.