A Look at Silverfish

If you’re squeamish about bugs, you may not want to read this one. I first researched this pest after finding one in my apartment. It scared the daylights out of me. The little bug crawled across my wall one night, wiggling it way back and forth, similar to what a fish looks like when it swims. It had about a million legs and long antennae.

The silverfish, a nocturnal insect, gets its name from its silvery color and its movement that resembles a fish’s movement. It is found in damp, dark areas of the home in temperatures between 70 and 80 degrees. There is a similar insect that is brown in color, called a firebrat. The firebrat generally prefers a warmer environment, over 90 degrees with high humidity, so they can be found in attics or near furnaces or water heaters. Silverfish may also appear brownish in color when they are not yet fully grown.

Silverfish require very little water to survive, and can live up to a year with no food. They thrive on starches or sugars. Therefore, they often feed on book bindings, wallpaper, and linens, but also on foods like sugar, flour, and cereals. They can also be found at times near sinks or baths, seeking the moisture found there. The insects tend to be more common in drier areas because they seek the humidity found in homes.

To sum up:

The Good – The insects are very rarely harmful. They pose no medical threat to humans, and the only real harm they cause is the psychological distress to those frightened by their appearance. They’re nocturnal, so if you sleep at night, you probably won’t see many of them. They are very common, so seeing these bugs doesn’t mean that you keep an untidy home. It mostly means you probably have ideal breeding grounds for them – damp and dark with crevices for them. They can even hide inside walls.

The Bad – In high numbers, they can be a nuisance, staining fabrics like clothes.

The Ugly – A silverfish lives about two to three years and an adult female will lay about 100 eggs in her lifetime. Large infestations only occur over long periods of time, so if you find you have a lot of them, you’ve probably had them for a long time.

Getting rid of silverfish. These insects need two things to survive: humidity and crevices in which to hide and lay their eggs. Limiting their breeding grounds will send them seeking a home elsewhere. Getting rid of old newspapers and books may help because you’ll be getting rid of their food supply. Also, using a dehumidifier or fans to reduce humidity may drive them away.

If required, lethal methods of removal are available. Using boric acid will kill the silverfish and is non-toxic to animals and humans. They can also be killed by freezing, but their eggs are not killed using this method.

Generally, they’re not harmful at all, though they can get to be in large numbers. The most harm that will come from having silverfish in your home is being startled by their appearance on occasion.