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Have checked the attic , few mouse droppings thats all, even lifted insulation, no rats or squirrel nests. Or bird droppings.
Are squirrels nocturnal?
This noise is was heard overnight, from an outside source very near to our bedhead. The gable ouitside is covered in wood lap and along the length of two of the boards are vertical scratches. If it was a squirrel and they are nocturnal, I would expect to see other boards with the same marks. The wood is sound and a tight fit,no gaps. it has be treated with 'Ducks Back' a waterproofing treatment which contains wax. It looks like something may have flown onto the wood surface and lost grip . Perhaps an Owl would do this?? Don't know, think this is one of lifes little mysteries. Last night was much quieter, or I was so tired from previous night, slept through it all.