Woodpecker, though a very defiant bird, has a couple of phobias, one of such is its hatred for mirrors. A woodpecker gets startled by the sight of its own image.
Owls are predators of woodpeckers and as such, a woodpecker would never be seen near an owl. One last hate the woodpecker has is noise. As long as the noise is not made by the woodpecker, that noise is displeasing to a woodpecker.