I finally decided to move the owl box to a new location. This is the 3 rd location and I am confident that this one will be a winner. The new location is on my lawn at the back of my garden. The box is on a 10 foot post and the entrance hole is about 7 1/2 feet from the ground. To discourage squirrels I put a baffle on the post. In addition the box is far enough from any trees which means that squirrels won't be able to jump onto the roof. The day after I put the box in the new location I had a pair of Screech owls calling in my river birch outside my bedroom window. I am hoping that this is a good omen. No sighting of any owls during the day.... It's still early days as the owls will only start nesting at the end of March.