Common Criminals
This trio of rodents accounts for 80 percent of animal break-ins.
MICE
Diameter of entry hole: ¼ inch or larger.
Likely entry points: Garage, basement, gaps around utility lines.
Signs of infestation: 1/8-inch-long droppings; smell of urine; noises at night; holes gnawed in food boxes.
Best spots for traps: Along walls; anywhere you suspect activity.
Preventive measures: Seal exterior gaps with mortar; weatherstrip the bottom of basement and garage doors; keep all foodstuffs in hard plastic, glass, or steel containers.
Stopgap measures: Stuff copper mesh or bronze wool into foundation cracks.
Job for a pro?: Probably not, but a large breeding population might require professional backup.
RATS
Diameter of entry hole: ¾ inch or larger.
Likely entry points: Garages, basements, rotted sills or foundations, damaged or unused drain pipes.
Signs of infestation: Black, greasy smudges around openings; smell of urine; ¼- to 5/8-inch-long droppings; nests of discarded food; fur; matted-down insulation; gnawing and squeaking at night.
Best spots for traps: Poisoned bait stations outside the house and around the perimeter of the property line.
Preventive measures: Eliminate all water and food sources around the house, including bird feeders and pet dishes; store food (pet and human) in airtight containers.
Stopgap measures: Cover entry points with hardware cloth or 16-gauge steel flashing.
Job for a pro?: Definitely.
SQUIRRELS
Diameter of entry hole: 2 ½ inches or larger.
Likely entry points: Where dormers meet roofs or where roof shingles overhang fascia boards. (The second-story men of household pests, squirrels can jump 10 to 12 feet through the air.)
Signs of infestation: Scampering noises in ceilings or attic; insulation missing from spots near eaves; ½- to 1-inch-long droppings; piles of nuts.
Best spots for traps: Live traps, clamped in place near the spot on the roof where they're getting in. Bait them with peanut butter, dried corn-on-the-cob, or suet.
Preventive measures: Prune trees away from house; keep roof and exterior trim in pristine repair; remove bird feeders.
Stopgap measures: Nail hardware cloth over potential entry points until they can be repaired.
Job for a pro?: You bet. Squirrels can carry rabies. Plus, it's tricky climbing ladders with traps, clamps, and jar of Jif.
