What Causes Silverfish?

causes-silverfish Credit: rawdonfox/CC-BY 2.0

Silverfish, or Lepisma Saccharina, are common household pests. The small silver creatures are nocturnal, so they may not be visible during the day. In moist or humid climates, it is very common for silverfish to reside in a home. Also known as fishmoths, silverfish and their eggs are transported by groceries, books or any type of paper brought into the home.

Even in a new home, silverfish potentially turn up with construction materials, eating the packaging and glue from the supply containers. Once silverfish arrive, it can be a challenge to eradicate them. Silverfish live in moist areas, such as an attic, a basement, a garage, a kitchen and bathrooms. They eat the carbohydrates found in common products such as adhesives and glue, paper, photographs and wallpaper. They love old book bindings and magazines but can also subsist on fabrics such as cotton and polyester. In a pinch, they infiltrate oatmeal, flour and sugar.

Silverfish life cycles range from 2 to 8 years, and they have the ability to produce more than 100 offspring in their lifetime. They can live for nearly a year without eating, so while that makes infestation difficult to eradicate, it isn't impossible to rid a home of these pests. To purge a home of silverfish, old magazines and newspapers must be removed or sealed in tight containers. Wet or molded wood needs to be repaired or replaced, with all crevices sealed with silicone caulk. Pantry foods such as sugar, flour, starch, oatmeal and coffee must be sealed in tight containers and plastic bags.

There are many safe, effective treatments to eliminate silverfish, including bug traps with special vanilla-scented glue to attract the critters. Installing dehumidifiers in or near bathrooms and kitchens reduces the moisture in a home, while pesticides that contain boric acid help eradicate both silverfish and roaches. Safe, odorless pesticides can be purchased inexpensively from grocery, home-improvement and hardware stores.