From the Anchorage Daily News October 15, 2001
Inside, they can get into drawers, cupboards and other places you wouldn't imagine. Mice can jump straight up a good 12 inches. They can scale vertical surfaces if there's enough texture for a toehold. They can even swim.
Besides the droppings you can see, mice leave behind something you can't. It seems they have no bladder control. They ''go'' constantly, leaving a trail of urine across floors, countertops and cutting boards. This is how exterminators find them, using a black light to illuminate their travels and setting traps in the paths.