Mice

What mice look like

House mice are small, brownish-grey rodents with a pointed snout, large ears and a tail about as long as their body. Adults run roughly 175 mm from nose to tail tip and weigh 12 to 30 grams, which means a mouse can pass through a gap about the width of a pencil. People often mistake a young rat for a mouse. The giveaway is the head: small and pointed on a mouse, heavier and blunter on a rat.

Signs you have mice

• Droppings the size of a grain of rice, usually along walls, under the sink or at the back of cupboards.
• Scratching or scurrying at night, most often behind walls, above ceilings or under the floor.
• Gnaw marks on food packaging, baseboards, wiring or stored boxes.
• Shredded paper, insulation or fabric tucked into a corner, which is nesting material.
• A musky smell in a cupboard, basement or utility room that doesn’t clear.
• Greasy smudge marks along baseboards, where mice run the same route each night.

Seeing one mouse in daylight usually means there are more out of sight. Mice are active at night and stay hidden while they can.

Why mice come into Ottawa and Toronto homes

Mice want three things: warmth, food and a quiet place to nest. Our winters supply the first, kitchens and pantries the second, and wall cavities, attics, garages and storage rooms the third. They get in through gaps around pipes and vents, worn weather stripping, unsealed dryer ducts, crawl space openings, and the joint where the garage meets the house. In row houses, condos and apartments they also travel between units along shared walls and service runs, which is why a neighbour’s problem can quickly become yours.

Are mice dangerous?

They are more than a nuisance, for two reasons.

Health. Mice contaminate far more food than they eat, leaving urine and droppings on packaging, counters and inside cupboards. Contact with that contamination is associated with illnesses including salmonellosis and leptospirosis, and mouse droppings and dander can aggravate asthma and allergies, particularly in children.

Property. A mouse’s teeth never stop growing, so it has to gnaw. That means chewed food containers, damaged insulation, ruined stored belongings and, at worst, stripped electrical wiring, which is a genuine fire risk. Damage inside walls usually goes unnoticed until it is significant.

How to keep mice out

• Seal gaps around pipes, vents, dryer ducts and cables, and fit door sweeps wherever daylight shows underneath.
• Store dry food, pet food and birdseed in sealed containers rather than bags or boxes.
• Clear clutter in basements, garages and storage rooms, which removes nesting sites.
• Keep bins closed and away from the wall of the house, and clean up crumbs and spills nightly.
• Trim branches and dense planting back from the roof and walls.
• In winter, check where heating pipes and utilities enter the building, as these are the warm routes mice follow.

Prevention works best before a colony establishes. Once mice are breeding indoors, sealing alone will not clear them.

How GO! Pest Control treats mice

• Inspection. We find how they are getting in and where they are nesting, inside and outside, and confirm it is mice rather than rats or squirrels.
• Exclusion. We seal the entry points, because removing mice without closing the gaps only makes room for the next ones.
• Removal. We place traps and control products where the activity is, out of reach of children and pets.
• Follow-up. We come back to check the results, clear what has been caught and adjust the plan if activity continues.
• Advice. We tell you plainly what to change so the problem does not return.

We are licensed, insured and bonded, and we work in homes, apartments, condos and businesses across the Toronto GTA, Ottawa and Hamilton.

Common questions about mice