To mark their trails for other mice to follow.
Cats are excellent at keeping mice out of houses. If getting a cat is not a possibility, I suggest calling an exterminator who can rid your walls of mice without causing damage to your home.
It is not known which animal urinates most. Animals with smaller bladders however will urinate more frequently. Animals such as mice and rats have smaller bladders and will urinate frequently.
The mice will come out of the walls when they are looking for food. Place mouse traps near a food source (unset for two days to trick them to thinking the trap is safe). Once the mice are used to that food source, set the trap to catch them. If you prefer not to harm the mice, use mint. Mice dislike the smell and will run away.
Mice cannot eat books, books are not digestible by mice, however, mice can still gnaw on books and damage them. Mice gnaw on lots of things. They are known to gnaw holes into walls, for example.
Mice will nest just about anywhere they can find. They nest inside walls, crawlspaces, attics, storage boxes, closets, and clothing.
It is an instinct. Being out in the open makes them vulnerable.
Deer mice find homes anywhere they can, from in old car seats or in between walls of your house to literal cities made under snow and among tall grass.
Mice only climb walls if there is something to grip onto. They can't climb on walls in a house, unless the paint has some sort of grip to it. They can't climb glass, either. But when I got a mouse, there was a thin-grated air vent in the cage, and she hung onto that. =3
Deer mice find homes anywhere they can, from in old car seats or in between walls of your house to literal cities made under snow and among tall grass.
To find where mice are getting in, inspect your home for small openings or gaps in walls, floors, or ceilings. Check for chewed materials, droppings, or tracks. Seal any entry points with steel wool or caulk to prevent mice from entering.
What have you taken?
Yes. It's not an overwhelmingly strong odor if they're dry, but you can smell them.