We had them in the garage going after feed. I had an old brooder with a lid that had 1/4 inch hardware cloth, started to put the feed bags into that. It caught 2 mice. LOL wasn't expecting that! They tried to go through the hardware cloth and got stuck.
Traps are everywhere in the garage. I go by the amount of poop, to see if the population is under control. The bucket traps work, but then the thing has to drown, so I prefer regular old mouse traps.
In the henhouse, I put the traps inside shoe boxes, and cut two little mouse sized holes in the shoebox. That way the chickens can't get near the trap. You can go more permanent by using small plastic storage containers that have a lid.
Used to be a lot of missing feed. Hardly any now, and the poop isn't like it was either. Just keep them set and check daily for traps that need reset. Put them along the wall, where the mice run. Use peanut butter as bait.