House mouse infestations are a pain to deal with. While the mice just want a warm, safe place to live, they make a mess and destroy the innards of your house by chewing on wiring and insulation. What's really annoying is that they seem to keep coming back. Mouse control is about more than just getting rid of the current critters in your pantry -- you have to approach this from a whole-property perspective.
Your Yard Work Game Needs Improvement
If the mice appear to be coming in from outside, you need to make your yard less hospitable. That means cleaning up all of the hiding places that mice can use. Even in snow-covered yards, there are usually areas where mice can shelter and set themselves up for a run toward your house.
Clean up piles of leaves, and tidy the areas around shrubs that have not died back for the season. Move woodpiles away from the house and keep the general pile nice and clean. If you have scrap piles (for composting, recycling, or whatever), clean those up -- take them to the recycling center or do whatever you need to do to get them out of your yard.
You're Being Too Kind
Are you using live traps, the kind that let you release the mouse outside? You may be releasing the mouse too close to the house -- it will just find its way back in. You need to go at least a couple of miles away, which is cold comfort when you have a panicked, peanut-butter-covered mouse squeaking at you from a small plastic box.
Put the trap in a sturdy plastic or cardboard box and drive it far away. Find a field or another area that isn't near houses to release the mouse.
Extermination Isn't Everything
Extermination and removal are not the only methods you have to use. Exclusion is essential. All cracks, even small ones, around the perimeter of your house have to be sealed up. What may look like a hairline crack to you is a big open doorway to mice, who can squeeze through tiny places.
Contact a pest control company that treats for rodent infestations. The techs can inspect your house and yard and let you know where the mice might be getting inside, or where they might be nesting. If you can exclude the mice and clean out the nest, you should see a vast improvement in your rodent battles quickly.
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