RAP SHEET

Silverfish

Lepisma saccharina

low CASE #MWP-0012

Eating your grandmother's photos and your college diploma. No motive. No remorse.

How We Take Them Down

  1. Residual insecticide application in cracks, crevices, and along baseboards
  2. Dust application in wall voids, attic areas, and crawl spaces
  3. Dehumidifier deployment to reduce relative humidity below 50% in problem areas
  4. Sticky traps in bathroom and basement areas to monitor and reduce population
  5. Treatment of entry points and harborage areas throughout the structure

Prevention Tips

  • Use a dehumidifier in basement and bathroom areas — silverfish thrive above 75% relative humidity
  • Store books, photographs, and paper documents in sealed plastic containers or airtight bins
  • Fix any moisture intrusion, condensation, or plumbing leaks that create high-humidity areas
  • Caulk gaps around baseboards, pipes, and tile to remove hiding spots
  • Regularly inspect stored items in attics and basements for early signs of feeding damage

Fun Facts

Silverfish are among the oldest insects on Earth — they've been around for 400 million years and looked essentially the same the entire time. Evolution took one look at the silverfish and decided it was already done.

They can run at surprising speed for their size and move in a fish-like wriggling motion — which explains the name, if not the discovery experience.

Silverfish can survive up to a year without eating, but they can't survive low humidity. A well-maintained dry home is your best long-term defense.

They can live 2–8 years, which is an extraordinary lifespan for an insect. They will outlive your houseplants and your interest in that hobby bread-baking phase.

Field Notes

Silverfish are the low-threat, high-annoyance member of the pest world — they pose no health risk, don’t bite, and won’t chew through your wiring. What they will do is quietly destroy irreplaceable paper-based items: the childhood photo albums in the attic, the decorative wallpaper in the hallway, the diploma in the spare bedroom. They’re moisture-dependent insects, so finding silverfish indoors is always a signal worth investigating: somewhere in your home, the humidity is high enough that it’s attracting them, which may also point to a more significant moisture problem lurking nearby. They’re not an emergency, but they’re not something to ignore indefinitely, either.