Hi jackietb
If they’re mice, there probably isn’t a lot you can do, but when they are outside they don’t normally cause too much trouble, and don’t eat much. You never know, you might even get an owl popping in for a meal!
Although, when you say overrun, how many do you actually mean? And are some of them substantially different in size. Rats are substantialy larger in size than mice.
For more information re. rats, I collected some rat focused posts and put them in the post with link below, so you might like to check through those for ideas of how to deter rats. https://www.hedgehogstreet.org/forums/topic/rat-probelm/
It doesn’t sound a bad idea to clear out the igloo and stop feeding for a while, but just be very careful in case there is a hog nesting in the back. Some hogs may not have come out of hibernation yet.
Good luck and happy hog watching!
