Zimmer frei? - Die Baukunst der Spechte

They tap, carpenter, drum. Woodpeckers are the greatest builders in the bird world. They hammer far more cavities than they need. For the benefit of titmouse, pigeon, pygmy owl, squirrel and other cavity dwellers. To win over mates, woodpeckers drum at the highest frequency. And in their search for the greatest resonance, they sometimes tap on metal. Woodpecker holes in house facades cause resentments with homeowners and arguments among animal squatters: Is that room still free?