Silverfish

This insect grows to be about ¾ of an inch long and ranges from silver to brown in color. It has six legs, two antennae, and three body parts. Much like a fish, its width tapers from its head to the tip of its abdomen, which is adorned with two long cerci and one terminal filament. Silverfish also move a little like a fish, wiggling as they quickly disappear into hiding places.

If you would prefer to not have silverfish near your home, it is a good idea to address: 

• Leaky spigots that allow puddles to form and soil to become moist.

• Obstructed or broken gutters that allow water to run down the side of your home. When water is not properly channeled away from the wall of a home, it creates the conditions for wood rot and moisture build up in perimeter soil, both of which are attractive to silverfish.

• Trees, bushes, and other objects that create shaded areas where soil cannot be dried by the sun after it rains.

These tiny silver bugs are gross, but they are not known to present a health threat when they enter homes. They don’t bite or carry venom and they are not linked to the spread of human pathogens. If an infestation gets large enough, it may be possible for harmful bacteria to be spread from trash cans to food prep surfaces, but this is rare. Silverfish are not generally a kitchen pest. They prefer to live in moist basements, crawl spaces, and bathrooms.

These insects live on carbohydrates and sugars, but many of the things they eat would not be considered food to us, things such as shampoo, glue, natural fibers in clothing, paper, and dead insects. If they get into a pantry, they can be found infesting rolled oats, flour, and other starchy foods.

Silverfish love glue and, since glue can be found in wallpaper, clothing, book bindings, book pages, and a wide range of other products we have in our homes, silverfish can be quite destructive. If you have valuable clothes or books, it is important to store them in plastic totes to protect them from silverfish.

Reducing moisture outside your home, and sealing any cracks, gaps, or holes is a great start. If you’re seeing silverfish inside, the installation of fans and dehumidifiers in humid areas can drive these pests out. If these methods are not successful, it becomes necessary to use a limited and focused application of EPA-approved insecticide in accordance with safety regulations. For this, we recommend hiring a certified pest professional.

• Silverfish are mostly nocturnal and prefer to feed at night.

• When you find silverfish in your bathtub in the morning, this is because they crawl in to get a drink of water and can’t climb back out.

• Silverfish are sometimes cannibals, feeding on other dead or wounded silverfish.

• The presence of silverfish in a home is usually a sign that there is water damage to the wood of the home.

• Silverfish are fast runners but are not able to climb walls as fast as they run across horizontal surfaces.