Some time ago I set my tweed flat-cap on the back of the sofa. It must have slipped down behind it and while I knew it was somewhere in the house didn't bother searching for it. I came across it this morning but it had a number of holes about the size of a penny coin in the material.
Is this the work of murine miscreants or maybe moths?
Mice do make nests but I reckon you cap holes are moths. If a mouse had used it, there would be a fuzzy bundle in the cap made of the cap chewings plus anything else warn it could find, and maybe also the remains of food.
My parents used to live in an old house in the country and one day they saw a mouse run across the floor. It disappeared before they could catch it and then Mum found that it had nested under the settee cushions and she`d been sitting on the bloody thing every night which was hilarious. Have you checked under your cushions? It might be having babies under there.
Mouse traps dispatched more than a dozen of them and there's no trace of any left. The cap must have been lying there more than a couple of years. Goes to show how often the place gets a clean.