Facts About Silverfish

By Ann Olson

Silverfish are small, silvery insects similar to cockroaches. They can cause moderate damage to homes, due to where they feed. Silverfish have long life spans and are rarely seen during the day, making them difficult to kill. Silverfish are similar to firebrats, which also feed on household substances. According to Cornell University, silverfish have an expected lifespan of one to eight years.


Silverfish are half to three-quarters of an inch long. They are identifiable by their shiny silver scales, which cover their entire bodies. They have two thin antennae and very small eyes, almost impossible to spot with the naked eye. They typically have three appendages that grow from their backs, almost as long as their bodies.


Silverfish live in damp, dark areas in households in the United States. They tend to migrate near their food sources, which include starchy products, glue, cereal and flour. They prefer to hide in small crevices around the house, including the openings of windows, corners of shelves or cabinets and below floorboards.

Time Frame

Silverfish live for three years on average. According to North Carolina State University, some silverfish live up to eight years. Silverfish can also live up to one year without consuming food and usually rarely die from a lack of food.


Silverfish can damage wallpaper, books, food and wooden materials that are held together by glue. They usually leave behind holes or yellow stains after feeding on substances that contain protein, starch or glue.


According to Cornell University, people can prevent silverfish infestations by keeping crevices, cracks and other dark areas free from moisture. Sealing off small cracks prevents silverfish from inhabiting those areas. Applying insecticide drying agents to cracks and crevices helps kill off silverfish.