Got mice? How to build a better mousetrap.

This box is a simple solution for homeowners dealing with the annual mouse migration. Photo by Steele Hays.

By Steele Hays

It’s that time of year when, as the weather cools and the leaves fall, mice, voles and other rodents look for places to stay warm and dry, moving into homes, barns, greenhouses and other outbuildings. 

That annual migration is happening now in our area. 

“We’ve been selling a lot of mouse traps lately,” said Debbie Armstrong, a retail sales employee at Reny’s in Ellsworth. “This is the time of year they are scurrying around looking for someplace warm.”

Here are two tips about how to combat the annual mouse invasion and keep your home and other buildings from being mouse havens:

Build a mouse trap box

Local organic farmer and author Eliot Coleman of Cape Rosier wrote about this tactic in his book “The Winter Harvest Handbook.”  The idea is to construct a wooden box roughly the size of a shoe box with mouse-size entry holes about 1 ½ inches in diameter at each end. Mice and voles love to enter small, dark holes and they’re attracted to the boxes, especially when they’re placed next to walls.  

The trap box should be built with a removable lid or one that is hinged with a single screw or nail so that it can be easily swung open. Several online videos suggest another option: using a plastic fishing tackle box and cutting entry holes in its sides. 

Any type of mouse trap–or traps–will do when placed inside the box. Coleman recommends using unbaited traps placed next to the entries of the trap box so that mice and voles trigger the traps when they enter.  

“This solution has been, and continues to be, impressively effective,” Coleman wrote. 

It’s easy to find videos and written instructions online for building a trap box. The boxes can also be placed outdoors in gardens. One of the advantages of these boxes is that they prevent pets and other animals from accidentally being harmed by traps. 

Mellisa Petrik and Clay Rossignol of Autumn Moon Farm and Flowers in Brooksville have built multiple trap boxes and rely on them to protect their greenhouse crops and flowers. 

Use scents like peppermint oil to repel mice 

Debbie Armstrong of Reny’s recommends using peppermint oil, a method she says has been effective in her own home.  

“Mice don’t like the smell of peppermint oil,” she said. “It’s much stronger for them than for humans so they won’t come into the house or rooms where there’s oil. I put it into a diffuser (in a wall power outlet) or sprinkle some on cotton balls or wadded-up paper.” 

There are a number of commercial products available that work similarly to repel mice by scent. Another option is to use electrical-powered devices that emit high-frequency sounds that repel mice but can’t be heard by the human ear.  

Regardless of which method of mouse and vole control you use, it’s wise to try to reduce their populations as soon as cooler weather starts–before they have a chance to build nests inside and begin proliferating.