Silverfish are small, silver or pearl gray wingless insects that seem to appear out of nowhere. You'll find them in your bathroom, kitchen and outdoor areas. Silverfish are not harmful to humans but can destroy books, clothes, cloth furniture and food. Like other insects, silverfish come out during the night and crawl on counters, bathtubs, showers, on your bed and other surfaces. Silverfish do not bite humans, but they do eat materials and food high in starch, protein and sugar.

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Bathroom

Environment

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Man stepping into attic

One reason silverfish invade your home is that you provide an ideal environment. Silverfish need food and water to survive. Any environment where water and food particles are left to stand is ideal for silverfish. Likely areas include kitchens, bathrooms, basements and attics. The insects also reproduce in these areas.

Temperature

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Messy kitchen counters

Along with a source of food and water, silverfish need an environment that is not too hot nor too light. The insects prefer temperatures between 70 and 80 degrees F and areas that are dark, like under a bathtub or sink. Silverfish like to mate and eat in the dark. A light and hot environment forces the insects to take shelter somewhere else.

Neglect

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Woman cleaning kitchen

Another cause of silverfish in your home is failure to recognize a silverfish infestation and take steps to remove the insects. By dehumidifying wet areas in your home, removing food sources and eliminating standing water, you take away elements silverfish need for survival. You also can apply an insecticide to kill them.

Humans

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Newspaper on counter

Silverfish can also enter your home through books, papers, cartons and cardboard boxes. The small insects hide within the pages of books both new and old as well as within the folds of a cardboard box or carton. Silverfish also hide within stacks of paper and within other items you bring into the house.