8 Freaky Facts About House Mice

If you're unlucky enough to spot a mouse in your house, guess what? There's never just one mouse. You've got mice! And given that nearly a third of Americans admit they've had a rodent problem, it's well worth preparing for the inevitable invasion of these pests. Do it now!

Our cheat sheet here contains everything that you need to know about these critters, and how to kick them out of your abode for good.

Fact No. 1: Cheese isn't their favorite food

Cartoonists have led us astray! It's a myth that cheddar is a mouse's first-choice snack. Cheese, in fact, isn't even in the rodent's top three meals: fruits, seeds, and grains. At the end of the day, though, the insatiable omnivores don't actually discriminate. (Eating between 15 and 20 times a day, it would be hard for them to be picky.) When starving, mice will eat their droppings, their children, and their very own tails. (Sorry if you're eating right now.)

Fact No. 2: They can squeeze through openings the size of a dime

Because the critters don't have a collarbone, they are able to wiggle through holes as teeny as a quarter-inch wide.

"Mice enter homes through cracks and holes in walls, floors, and foundations," says Cindy Mannes, vice president of public affairs at the National Pest Management Association. "If drainage pipes are not properly sealed, mice can even get in the home through sink and bathtub drains."

Her advice? Seal cracks and holes on the outside of the home using caulk and steel wool, install door sweeps on exterior doors; and always store food in airtight containers and dispose of garbage regularly.

Fact No. 3: They mark territory just like dogs

Mice droppings are often the first sign of an infestation, and, unpleasantly enough, it's not a tricky one to detect. Mice aren't all that discreet about where they do their business.

Every day, a single house mouse leaves behind 40 to 100 pellets of feces (through which more than 35 diseases can be spread). But their liquid waste is even more alarming.

Male mice constantly release droplets of urine to mark their territory. If another critter comes along, he'll often challenge the claim with a " countermark" of his urine. And this pissing contest isn't just gross, the pee also poses a significant health risk for humans. Studies show that the proteins in mice urine can trigger allergies and asthma.

Fact No. 4: One mouse can pop out 150 babies a year

Rabbits may have the reputation for always getting busy, but they've got nothing on mice. Female mice are able to have up to 12 babies every three weeks beginning when they're just 2 months old. The possible grand tally? About 150 babies in 12 months, turning a small rodent problem into a big one, pronto.

Fact No. 5: Their teeth never stop growing

Unchecked, mice are practically unstoppable thanks to their ability to chomp through most barriers, including plastic, rubber, vinyl, insulating foam, wood, drywall, and even electrical wires. The biting isn't just about breaking through to stashes of food, either.

"Mice gnaw constantly to keep their teeth from overgrowing," explains the expert. Mice teeth, in fact, never stop growing. Chew on this: If they aren't worn down by gnawing, each of the vermin's 16 teeth will grow up to five inches a year.

Fact No. 6: Cats can't help much

Wouldn't it be great to just rely on your feline to take care of business for you? The truth is, not all cats are capable of catching mice, nor do all want to. Many simply tolerate mice if they're being well-fed already. The idea that mice will avoid a cat-filled home is false, too, unfortunately. Sure, the rodents may smell a predator on-site, but if they're hungry enough they'll venture out and about anyway.

Fact No. 7: Old-school snap traps are the best solution

There are lots of DIY ways to catch and kill rodents in your home. Mice baits, aka rodenticides, are essentially pesticides disguised as mice treats that attract and kill the vermin that ingest them. The problem is, they often fail (if another source of food is available, rodents will ignore the bait) and they pose a poisoning risk to pets and children who could get a hold of them.

Furthermore, if a mouse retreats behind a wall and then dies, you've just bombed your house with a rotting carcass you'll have to tear up the baseboards to find. Instead, the Centers for Disease Control and Prevention recommends snap and also electronic traps. Each kills a rodent on contact, via spring-loaded bar and battery-powered electric shock, respectively. Glue traps and live traps, though, are a no-no, the CDC adds, since trapped mice freak out and pee, thus exposing you to all the diseases that you're trying to avoid. Rats!

Fact No. 8: They have facial expressions like ours

Just when it's tempting to think of a mischief (the actual term used to describe a group of mice -- fitting, right?) that has infiltrated your home as the devil's spawn, consider this: Mice in pain have facial expressions so similar to humans that scientists have created a " mouse grimace scale" to evaluate the efficacy of new drugs that they're testing on rodents.

Aching mice apparently squint their eyes and bulge their noses and their cheeks just like us. OK, now we're really weirded out.

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