I think 12 by 12 is probably too small for a hog to build a hibernation nest in, but I agree, a good home for other small wildlife if a hog turns it down. You could make a good bug hotel with a box that size. Just fill it with bits of wood of different diameter (with the ends towards the entrance to the box), with maybe the odd bit of corrugated cardboard rolled up. I have done a similar thing on a larger scale with an old tea chest. It had only been in place a few days before some bumble bees moved in. But there are loads of other bugs, spiders, etc. living in there.
I think it’s probably alright if you insulate before a hog moves in, as they know what they’re dealing with then. But not afterwards. I would avoid plastic.
How to think like a hog – not easy, especially as they seem to like to keep us guessing!
