I had Starlings going in the guttering and up under the slates and felt into the roof space over the bedroom making a nest and waking us early mornings. I hung a Magpie decoy on the gutter were they were getting in, it worked for a few days as they would not go anywhere near the decoy.Then they found a way in 10 foot from the decoy so I put another Magpie decoy there which, during the next night was attacked twice by an Owl.First hit woke us up and the second hit I had my head out of the bedroom window looking for the cause of the noise.
The Starlings then became accustomed to the Magpies and would sit adjacent to them and continued building the nest.
l left them to it as by now they had young. When they fledged I rolled chicken wire and lay it in the gutter.
They have been back this year looking for entry but failed to get in.