Actually, their correct name is “Silberfischchen”, but they are more commonly known as “Silberfische”. Their silvery or mother-of-pearl scales speak for the naming, but it is their feeding behavior that gives them their technical term “Lepisma saccharina”: Translated, it means “sugar guest” – because they need sugar to survive. They do not feed exclusively on organic waste such as hair and dander, but also on starchy foods such as flour, cereals or pastries. So it is hardly surprising why the insects feel particularly at home in human households. Where exactly and why you do not necessarily have to fight all silverfish is explained below.
In Central Europe, silverfish live mainly in heated living spaces – preferably where it is not only nice and warm but also damp: in the bathroom, in the kitchen or in the room where you hang up your damp laundry. The absolute comfort temperature is between 25 and 30 degrees Celsius, but if it gets too hot (from 35° C), they die. On the other hand, if the temperatures drop below ten degrees, the insects become inactive. If it is too dry, silverfish can no longer reproduce: a female lays up to 20 eggs.
During the day you rarely see the silverfish, if at all, because the animals are afraid of light and only become active at night. For this reason, they hide wherever it is dark: in cracks or joints or behind skirting boards or wallpaper. If you catch the insects in the act, scurrying across the floor or disappearing behind the wall, you don’t have to panic immediately – because the fact is that the animals are neither harmful to health nor a sign of poor hygiene. On the contrary: silverfish are actually useful.
Many an infestation, such as that of food moths, should definitely be fought, since the insects contaminate food and their residues can trigger allergies and gastrointestinal diseases. Silverfish, on the other hand, are not harmful to our health, instead they even have a practical use: Apart from the fact that they eat house dust mites and are therefore good for allergy sufferers, a heavy infestation can indicate a moisture problem in the home – because silverfish also eat fungal spores. If there are large numbers of insects, you should check your four walls for possible mold growth.
Even if silverfish are harmless in principle, insects trigger a real disgust in many people. Therefore, you can take preventive measures so that the animals do not feel comfortable in your home and run away:
Since silverfish prefer warm and humid rooms, you should air them regularly – this applies in particular to your bathroom. The colder the air and the lower the humidity, the more uncomfortable it is for the insects.
Since organic waste such as hair and dead skin flakes are part of the silverfish’s diet, you should vacuum and wipe all rooms regularly, or wipe them with a damp cloth.
Since the light-shy insects stay in dark cracks and crevices or use them as entrances, it is best to seal them off as best you can – with joint filler or silicone, for example.
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