By Russ and Tiña De Maris
It all started with a letter from Don Callahan, a long-time RVtravel.com reader. Here’s Don’s missive: “I read in a number of places that Irish Spring bar soap was a deterrent to rodents in RVs. I put a number of bars around in my motorhome last fall when I stored it. Today when I was going to install the chassis battery I found that the two bars of Irish Spring I had placed in the battery box area had been partially eaten and there were a lot of mouse/vole droppings around it. Amazing.”
Don is an Alaska resident. Are cold-weather mice hardy? Or, after several long months of winter, maybe they just need a good bath, and a few nibbles of Irish Spring and a breaking of the ice on a nearby puddle are all they need to get spiffed up for spring. In any event, it brings up the perennial question: Just what can you use to successfully keep rodents out of your RV?
Certainly Irish Spring falls under the old odiferous offering category. You can add to it moth balls and cotton balls dipped in peppermint oil. The theory goes that since mice and their kinfolks have sensitive noses, putting out something that is proboscis potent should send them fleeing into the next county. Good in theory, but usually not too effective in practice. Why is that?
First, a little mouse psychology. Put yourself in a mouse’s place. If all your enemies were bigger than you, had sharp teeth, and were terrifying, just how quickly would you be willing to move out of a safe shelter where the big guys couldn’t get at you? Would you be willing to put up with a little smelly stuff to have a safe place? Think rats in sewers. Tell me, just how bad does a sewer smell? Yes, it’s possible that if you could whip up a stinky batch of Irish Spring, peppermint oil and moth balls you might be able to run off the rodents – but think of what the stuff would do to you.
Perhaps peppermint-scented cotton balls will deflect Herman the Mouse, but unless you put them just about everywhere in your RV it’s quite likely they’ll just learn to avoid the immediate smelly area. The same seems to be so for the next techno-mouse repelling idea.
Ultrasonic shooing systems
Described by one marketer as “unique devices that are designed to drive away ants, spiders, mice, rats and cockroaches only using ultrasonic sound waves,” these not-so-cheap electronic devices are sworn enemies of mice and bugs. The marketing trumpet goes on, “That means no unpleasant odors or dangerous chemicals to inhale and no messy, toxic sprays that may put your pet in danger.” Do you buy that?
If you do, remember, you probably also left a bunch of cotton balls lying around in the bottom of the dinette cabinet, soaked in peppermint oil. Now envision hordes of mice making a beeline for your dinette cabinet, grabbing ahold of those same cotton balls, ripping off chunks, wadding them up, and stuffing them in their little mousy ears. They smile as they go about their daily routines in your RV, now oblivious to your “unique devices.”
Once again, strength and area are problems for these dream machines. In order to be safe for pets and users, the noise strength of these clever devices has to be kept down to a dull roar. Even if they were like the proverbial “fingernails on the chalkboard” to rodents, the intended target audience would simply move out of the effective range of the device.
Many of these potent potions really do spell death for mice. But they also come with their own set of drawbacks. Some of them are consumed by mice, who don’t die instantly. Some cause the critter to develop the effective equivalent of a hemorrhagic disease – their blood vessels start leaking out their vital fluids in a torrent. No doubt the mouse feels terrible, so instead of dropping dead on your kitchen floor, he drags himself off to a quiet, dark and sheltered place to die. Come time to travel, you only know the stuff was effective when you open the door and smell the decomp. Now try and find that quiet, dark and sheltered place to retrieve that body!
Some years ago we had a bad infestation of mice in a food storage area. We put out little boxes of green pellets, guaranteed to make mice beg for their last meal. The mice found the stuff – and carried it off to the other end of the rig where they carefully squirreled it away in a sofa. Enter three-year-old grandson – who made the remarkable find in the couch. Picture terrified grandparents dumping ipecac syrup in the squalling kid’s mouth in an effort to get him to upchuck the mouse poison. He survived, and now has a rug-crawler of his own, but the nightmare really never goes away.
Forget the stuff that doesn’t work. Throw out the ideas of poison baits that can create bigger problems than they cure. Here’s what REALLY works:
Cut off the food supply
Your rig is a great haven for mice, but only if they have the necessities of life. When you put your rig in storage, make sure you don’t leave stuff behind that rodents will find life-sustaining. You like to snack while RVing? So do mice! Don’t leave behind stuff like crackers and chips. A box of Cheerios is great cheer for a hungry mouse. And stuff you might not immediately think of includes powdered coffee creamer, sugar, flour and baking ingredients. Uncooked pasta, nuts, dried fruit and trail mix, candy and granola bars are easy mouse targets.
And don’t think that your precious commodities that you’ve carefully concealed in plastic containers with sealed-tight lids will keep away a determined rodent. With plenty of time on their little paws, busy teeth can make for holes big enough to access tasty snacks.
Roll up the draw bridge
Secure your rolling castle by keeping the rodents outside your walls. Mice can squeeze through tiny cracks and holes and come in like an occupying force. It requires effort, but you need to make a thorough inspection of your rig. Crawl underneath and look for any cracks or holes. Inspect where utilities enter or leave – electrical port, water hatch, gray and black water pipes passing through the floor. Expanding foam, cautiously used on some things, will do a pretty good entry prevention trick. Steel wool is also another great hole fixer – mice can’t chew through it to gain access.
Keep your rig clean, remove any attractive food supplies when the rig isn’t in use, and always ensure that the welcome mat is never extended by keeping all outside access to your rig closed off. And what if an enterprising rodent still makes it in? We found spring traps, baited with peanut butter, were simply irresistible to a fat little mouse that had the audacity to eat raisins right off our galley counter while we slept.