By Christa Rolls, USAG Bavaria Environmental Division
GRAFENWOEHR, Germany — If you have been in a local car shop, you’ve likely seen products that tout a hissing, ferret-like animal on the front cover, warning of their presence.
Martens, or Marder in German, notoriously damage vehicle electrical systems by chewing on exposed wires and tubes beneath a car’s hood.
According to Gesamtverband der Deutschen Versicherungswirtschaft, a German auto insurance company, martens account for tens of millions of dollars cumulatively in damage to car cables each year.
These animals may be portrayed as vicious, but in actuality they are misunderstood.
Martens, specifically Stone Martens (Martes foina), are small mammals with long, furry bodies. They are crepuscular or nocturnal— or active at twilight or nighttime—so they are difficult to spot any time of day.
While a handful of studies have been completed on the subject, it is currently not known exactly why martens exhibit chewing behavior on vehicles.
Their territorial nature is the most likely explanation, where martens feel the need to exhibit dominance by marking objects, including cars, within their territorial area.
There are other hypotheses that suggest the coating found on wires or cables attracts the martens, inviting them to have a bite. Or, while taking rest and refuge in the hood of the car, they simply get curious and take a nibble.
Trapping and hunting of martens in Germany is illegal, unless performed by a designated state certified trapper and hunter. Trapping is not a viable option.
There are, however, a number of established ways to deter martens. The effectiveness of these deterrents have not been studied in detail, and users report positive results in only some cases.
While martens have a keen sense of smell, repellent sprays can be put under the hood of the car, and ideally will detract them.
Alternatively, small acoustic machines with a built-in infrared or movement sensors can be installed at the parking spot to emit a very high-pitched sound thought to scare away martens as soon as they approach the car.
There are downsides to both of these repellents, as sprays can leach into the surrounding environment, and acoustic machines may allow sneaky martens to slip past the sensor.
The noise emitted, too, is quite jarring, so if kids or pets are in the surrounding area, they’ll likely hear this noise every time they pass by. The noise can also negatively impact other unsuspecting wildlife, including birds.
One less invasive deterrent is building or purchasing a marten grid, or Mardergitter, to be placed under the engine compartment while the car is parked. The gridded metal or mesh acts similar to the way a cattle grate deters cows from crossing through a gate. It’s supposed to prevent martens from getting under the car.
It is possible to purchase wire grids to drive over directly, however, some grid users have claimed that having the mesh sit at least an inch off the ground on a wooden frame—giving the impression of a drop-off when the marten’s paw slips through the wire—deters the animals.
For more information about martens and other wildlife, follow the Environmental Division on Facebook or visit home.army.mil/bavaria/index.php/environmental.