We had a similar experience a number of years ago with a Flicker. First thing we knew about it was when we found pieces of insulation scattered around the yard. We covered the opening by nailing the base of a coffee can over it, but I swear the bird was watching, since he then started another hole about five feet further up, out of reach of the ladder that we borrowed from a neighbor. We tried all the usual things like hanging pieces of foil, putting up a plastic great horned owl, none of which worked. Eventually the bird gave up as I guess it decided it wasn't a suitable nest site. Just be grateful it isn't a Pileated. We had a pair attack a second floor window frame and ended up having to replace the window. When we took a photo of the window to place the order for the replacement, we realized that the window was highly reflective and that the birds were probably attacking their reflection. We hung a piece of screen cloth over the window and that seemed to do the trick. Wendy Ealding Chesterfield County