My brother once had a cabin in the mountains and kept it fairly well stocked for the periods of time when he'd go gold prospecting.

On one trip he decided to leave his boots there for the next time so he hung them from the ceiling joist to keep the vermin out.

A couple of weeks later he went to take down the immaculate boots - he found both of them almost completely full of pinecones.

Check your ceiling joist, oddude.