Making an impression

YOUR article on the short-eared owl (Notebook, November 3) gained my attention, as we came back from a short break to discover this amazing imprint (only visible in darkness) of head, body, wings and feet on our drawing-room window. We are advised it was an owl and that the bird is a great survivor when it comes to striking solid objects. No sign of feathers, blood or bird. Do your readers have any ideas? John Stace, Somerset