The 6 confirm-it signs
1. Sounds in the walls or ceiling at night — light scratching, soft pattering. Mice are nocturnal; you almost never hear them during the day. 2. Droppings: small (¼ inch), dark, pointed at the ends. Found in drawers, under sinks, in pantries, on top of cabinets. 3. Chewed cardboard, paper, or insulation — especially around pet food, dry goods, or stored items 4. Greasy "rub marks" along baseboards, around pipe collars, and at the top of foundation walls — mice run the same paths repeatedly 5. Pet food disappearing overnight, dog kibble in unusual places 6. Faint musky / urine odor in confined spaces (under-sink cabinet, basement closet)
What's NOT mice
- Squirrels in the attic — heavier, scampering during day, much louder
- Bats — usually only at dusk + dawn, sounds in the eaves not the walls
- Birds nesting in vents — chirping, distinct from rodent scratching
Why you can't wait
A breeding pair of house mice in optimal conditions can produce 5–10 litters per year, 5–8 pups per litter. The math gets ugly fast:
- Month 1: 2 mice → 8 mice
- Month 3: ~28 mice
- Month 6: 100+ mice
- After 1 year: 2,000+ theoretical, ~150 practical given resources and territory
Mice also chew electrical wiring (~25% of "unknown cause" house fires are attributed to rodents) and contaminate food storage.
The right response
Snap traps placed perpendicular to walls (where mice run) outperform glue boards and poison stations for in-home mouse problems. But traps alone don't fix it — you need exclusion (sealing every entry point larger than 1/4 inch). Read about our mouse exclusion process →