by Russ and Tiña De Maris
With RVers hopeful that spring and summer travel will get a green light – even if on a limited basis – their thoughts may have turned to getting the rig ready to roll. Trouble is, not only do we like our RVs, sometimes rodents like our RVs too. Not surprisingly, we may find our prized motorhome or trailer has become the wintering grounds of the cagey mouse. And why not? Much warmer than being outside, certainly dry, and usually full of suitable food in the form of leftover breakfast cereal, rice, dry pet food, and potato chips. With easy access points for a mouse to move in, you may as well have put out the rodent equivalent of a welcome mat last fall.
Popping open the fifth wheel door that withering smell of mouse residency wrinkles your nostrils. Or, maybe the mice have decided your hide-a-bed is an ideal place to “hole up.” The smell and physical damage of nesting mice is bad enough, but their “calling cards” can actually be deadly: Deer mice are known carriers of Hantavirus, an often deadly-for-humans airborne pathogen. All excellent reasons for keeping these critters outside your RV.
How do you keep rodents out of your rig? And if they’ve already let themselves in, how do you get rid of them? We posed these questions to Marty Pullen, a professional pest exterminator. Marty is a jovial fellow, always quick with a laugh, and with a deep sense of being a scholar of pests of all sorts – and that’s probably a good thing. If you have to deal with creepy-crawlies every working day of your life, it’s best if you really have an abiding interest in the life and times of said creatures.
Keeping the creeps out can be a bit of a challenge. Marty waxes eloquently on rodent physique. First, the term “rodent” comes from the Latin, meaning to “gnaw.” Mice and their kindred have teeth that constantly grow, and to keep themselves happy they have to gnaw to keep their teeth from getting too long.
While visions of mice gnawing their way into your rig are probably overstated, they do have another physical trait that can make keeping them out challenging.
Rather than having a skeletal structure like humans, mice are more cartilage-based life forms. This peculiar structure allows a mouse to squish itself through a hole as small as 1/4 inch. RVs often come factory-equipped with mouse-portals meeting this requirement. Think about where your power cable ports through into the rig. Or how about a hose port? And as the years and miles roll by, the constant vibration and pounding can make formerly tight joints loosen, thus making space enough available for these determined little critters’ access.
What to do? A thorough inspection of your rig is essential. Look for cracks or holes that might make mouse access possible. If you find a likely spot, you need to close it up. Since “rodent” means to “gnaw,” filling the holes requires the appropriate agent. For larger holes, try filling them with steel wool. Apparently mice find this wiry substance indigestible. Long running cracks might respond to a heavy-duty caulk – consider acrylic sealant from the RV store.
What about the problem of mice-in-residence? First, you’ll need to look for evidence of their existence. Marty tells us that mice are prolific in more ways than one. The average mouse produces about 25,000 droppings per annum. While I’m not suggesting a scatological survey to determine how many mice you have, just look for calling cards. Since rodents can have a litter every six to eight weeks, and the little baby mice will be ready to have their own family in as little as six weeks, rapid riddance of furry interlopers is essential.
Placing the trap is half the battle. But mice are predictable, which makes establishing the battle plan a little easier. Mice rarely travel to eat much farther than 20 feet or so from their established nest, and they establish routes called “runs.” Typically a mouse run is along a wall. Long runs of cabinetry in RVs are often open underneath, rather than compartmentalized like home cabinets. Hence, check for mouse droppings under your sink cabinets.
According to Pestman Pullen, mice are neophobic – they have a fear of new things. Hence, sticking out a baited mouse trap to nail these guys is not the best first step. “Pre-baiting” is the way to start. Bait – but don’t set – your mousetrap and place it along a suspected mouse run. What bait? Everybody has a suggestion, from the time-honored cheese to the modern’s peanut butter (would that be crunchy or smooth?). Marty has his own favorite: “Sew a cotton ball on the bait latch,” says the veteran hit man. “Then soak the cotton ball with vanilla extract.”
Apparently the odor – and perhaps the taste – of vanilla is irresistible in the mouse world. And mice love to have soft substances to make their little beds out of. Sewing the cotton ball to the bait latch not only assures you that the cotton will be there when you return, it also guarantees the mouse will have to really tug on it. By pre-baiting with the trap unset, the mice will overcome their neophobia. After a few days, when the mice have determined that the trap is not a threat, return and set the trap to “T” for TERMINATE.
When disposing of your victims, take precautions with your health. Wear rubber gloves and a dust mask. If you intend to reset the trap, take the offending mouse away and give it a proper – and safe – burial. Place it in a plastic bag and seal the bag before tossing it in the garbage. If you’ll be removing the trap, douse it thoroughly with a bleach water solution to kill any Hantavirus. NEVER use a vacuum cleaner to clean up mouse droppings. Instead spray them with bleach water, then carefully collect them with paper towels, disposing of droppings and towels as you would a dead mouse. And if you do encounter a mouse infestation in any enclosed space, open the door and thoroughly air the place out before entering, properly attired with a dust mask. Can’t find one? Use a cloth substitute, as you would when venturing out in public.
Mice may be cute little guys. Those popping little eyes and wiggling whiskers make them seem adorable. But the thought of drowning in my own bodily juices, which is the final aspect of catching Hantavirus, causes me to sprint for the steel wool. Mice are nice – outside my rig – or inside our cat.