You may have heard of people with bats in their belfry, but how about rats in their manifold, or mice in their motor?

It is only a rumor that small autos are powered by hamsters running full speed on whirling exercise wheels, but rodent residency of engine compartments is not a total myth.

In fact, the damage done to vehicles by mice, rats, and their many cousins can be considerable. Gnawing wires, ripping out insulation for nesting materials, or squirreling away caches of nuts and other treasures in car and truck engines can wreak havoc on some of man's most sophisticated transportation technology and cause a significant finantial loss. This is especially true if you live in a rural area.

Seldom used vehicles are not the only ones which inspire vermin thoughts of habitation. Sierra foothill resident Glennis Tribe found out that furry critters were apparently as excited as she was about her brand new car. In less than 24 hours they managed to destroy much of the wiring.

"The plastic insulating material that is now being used must be especially tasty. It's like caviar to rodents," says Tribe ," they chewed all the wires that connected batteries or alternators or anything electric to anything else. It was rather costly! "

Five months later it happened again. Tribe now has a small electronic deterrent device which sends out rodent- disturbing signals warning tiny intruders to back off. She makes sure it is properly connected each time the car is parked.

"Apparently they have nothing but time," says Rick LeDuc of Rick's Automotive Service, who has found elaborate nests in intake manifolds, and even litters of tiny pink mice inside densely re-insulated air cleaners. In one of the more ambitious nests, he found a section of broom handle that had been dragged into the inner workings, as well as "a couple of pounds of dog food." In another instance, he said that only the wires coated with blue plastic insulation had been gnawed. "They are supposedly color-blind, but sometimes they pick out one certain color of wire to chew," he insists.

Several auto repair businesses report that they have numerous incidents of rodent damage each month. The time of year doesn't seem to matter. Hoarding, nest building and wire gnawing are year round occupations. Mechanics say that the animals favor newer cars and trucks, but they also plague vehicles which are parked for extended periods of time. Repair costs can sometimes be as high as $500. In at least one case where so much wiring damage was done that the car was not worth fixing.

People sometimes come into a repair shop complaing that they "smell something burning". The diagnosis might be feather duster plumes tightly packed into a carefully fabricated nest, pine needles jammed into tight spaces, and actual culprits, both living and defunct. A lot of people are surprised to discover the source of their problems.

Why have so many furry occupants taken up residency in a space where renters are not welcome? Are they planning to take over the planet by disabling our vehicles? The real reason they seek an unnatural habitat under a hood, is that it provides a dark, warm, secure place to hide.... at least until the ignition key is turned. Machinations of vehicle start-ups can be deadly for the critters, and sometimes can cause serious consequences for the drivers as well.

An acorn, rolling into a crevice after a driver stepped on the gas pedal, kept the throttle open on a late model Ford truck. Brakes were damaged before the driver could shut down power on a winding country road. The wood rat culprit had apparently abandoned ship before the adventure, but his hoard of nuts almost caused a real disaster. The truck required towing and lots of professional attention.

John Muir, the famous Yosemite naturalist, called the Wood Rat, " a handsome, interesting animal". In his detailed descriptions of Sierra flora and fauna, he also opined that " No rat or squirrel has so innocent a look, is so easily approached, or expresses such confidence in one's good intentions."

The colorful comments of many vehicle owners who have been plagued and bedeviled by by these damage- causing beasties is usually much less complimentary, and often unprintable. Those who have been their victims have long since abandoned any "good intentions".

Muir recorded incidents of rats stealing combs, eating utensils, nails, tin cups and spectacles which he supposed were used for the purpose of strengthening it's nest. Quite possibly it was easier for the poetic naturalist to appreciate the animal, since he usually traveled on foot, rather than by SUV.

Wood rats or pack rats are notorious for gathering and accessorizing their nests with varied accumulations. Their collectibles range from natural curiosities like bones, cones, and stones, to the tools, trash and treasures furnished by humans. Once they have found their way into an engine compartment, the rats must think they have found the mother lode of wonderful man-made objects, with wires and hoses and tubes connected to a spectacular variety of shiny metal and plastic components. To this assemblage, they will add their acorns, pine needles hardware items, bottle caps and whatever ornaments suit their eclectic decorating style.

Even before the era of motorized vehicles, people have contended with these tiny terrors. Early settlers did their best to keep rats and mice out of their houses and barns, even though hard rock miners actually encouraged rats to inhabit the mine tunnels. There are tales of miners saving crusts and crumbs of bread for the rodents who acted as a kind of low tech safety system. The rats, being ultra sensitive to tremors or quakes could provide early warning for impending collapses or cave-ins. When the rats suddenly went running for the exit, the mine workers were close behind.

So how can pesky little wire nibblers and insulation grabbers be discouraged? Could a car be disguised with with animal pelts, to make it look like a rat eating predator? Would a ground squirrel be tricked into thinking your car was a mountain lion or a giant badger with the help of a spectacular paint job? Or perhaps one of those big plastic owls could be stuck under the hood, and wired it up with a speaker playing annoying rap music.

Some people park their car over a bucket of mothballs, which is apparently repugnant to rat olfactory perceptors. Other simply leave their hoods open, eliminating the darkness and privacy sought by invasive mammals. Traps, baits or poisons are used by others.

The family dog or cat may help to keep mouselike pests away, though if the cat gets into an engine, it's bad for everyone ..... usually worst for the cat. Some say that even a little bundle of dog hair or cat fur has the power to repel the nuisances. Others swear by the electronic devices used to repel gophers .

There are also little buzzer things that are supposed to keep pets of the furniture. They might work.

The problem is not going away, so drivers might be wise to pay a little extra attention next time they notice an unfamiliar squeak in their vehicle.

They are out there. One of them knows where you park your car.