Martens hunt cables: damage running into millions
Various “home remedies” are recommended on the internet: a wire mesh under the car, since martens dislike walking over wire; human, cat, or dog hair as a deterrent; toilet blocks, mothballs, or scented sachets placed in the engine compartment. The effectiveness of these remedies is, however, disputed.
The biting begins now: in June, the mating season of stone martens gets underway. The males fiercely defend their territory during this time — uncertain times for motorists, especially those who commute between locations frequented by different martens in the engine bay. These small predators love the snug space under the bonnet: a cosy den to feel at home in. Even the scent of a supposed rival leaving its mark can disturb their sense of comfort. In that moment, ferocious biting attacks are virtually guaranteed.
Motorists without a garage should expect martens to target, for example, the spark plug cables or the brake and coolant hoses of their cars. This can turn out to be costly. In Germany alone, martens caused more than 200’000 cases of vehicle damage to their customers’ cars last year. Martens cause annual damage of more than 60 million euros to motor vehicles.
With a total length including tail of up to 90 centimetres and a weight of around two kilograms, these curious predators can also catch squirrels and birds. Stone martens can be identified by the white throat patch on their brown coat — and by their weasel-quick movements.
But it can be not only costly, but also dangerous. The damage often goes undetected, as the sharp little teeth of these predators frequently leave only pinprick-sized punctures. While driving, secondary damage — to the engine, for instance — can occur quite quickly. Keeping an eye on the coolant temperature gauge helps: if the needle moves into the red zone, a look under the bonnet is essential.
Partial comprehensive insurance (Teilkasko) generally covers marten damage. Nevertheless, it is worth reading the fine print, especially with regard to consequential damage: if sensors or other sensitive components are affected as a result of marten bites, repairs can quickly become costly. In some cars, for example, the lambda sensor cable is very easily accessible. If this is damaged by marten bites, the exhaust emission control system no longer functions properly. Steering rod or driveshaft gaiters are also popular targets for martens. If these are damaged, joints may no longer be properly lubricated and can sustain damage.
If the small predator has attacked the hoses and cables of cars, campervans, or motorcycles, fully comprehensive insurance (Vollkasko) also applies, of course. However, bear in mind that anyone who files a claim will be downgraded in their no-claims bonus.
Prevention is better than repair
There is no miracle cure that keeps martens out of the engine compartment. However, car owners who want to avoid all the hassle of breakdowns and repairs can at least make it harder for martens to bite through things.Sturdy cable sheaths for vulnerable components, available from specialist retailers, are effective and affordable. In addition, special devices for sealing off the engine compartment – as offered by some car manufacturers – take the fun out of cables, insulation mats, and water hoses for the little predator. Occasional engine washes are also said to help. They remove all scent traces from the engine compartment that attract other martens. Only a closed garage offers truly reliable protection.
Ultrasonic devices also provide more dependable protection. High-quality products have a variable frequency (> 20 kHz), variable pulse duration and pulse sequence (random generator), and a sound pressure level of at least 100 dB. They are also resistant to moisture, vibrations, and temperature fluctuations, and consume little power. Where the surroundings permit, an ultrasonic device can also be installed near the car.
