Silverfish and firebrats are sometimes known as “bristletails.” The silverfish lives and develops in damp, cool places (prefer 75%–95% relative humidity), while firebrats prefer places above 90° F. Adult silverfish and firebrats are 1⁄2-inch in length. They are wingless insects with two long, slender antennae, and a flat carrot-shaped body, covered with scales, that tapers down to three long “bristles” at the end. Both silverfish and firebrats move fast in a wiggling motion, resembling the swimming action of a fish.

Houses provide a perfect habitat for silverfish. Preferring moderate temperatures from 70°–80°F, and a relative humidity between 75%–95%, they collect near sinks and other plumbing fixtures in bathrooms, kitchens and basements. Silverfish are most often discovered in sinks and bathtubs, though they can be present throughout the house. Silverfish are frequently introduced with newly installed dry wall, feeding on the paper backing and occasionally large populations form within new buildings where the walls are still damp from plaster and fresh lumber.

Firebrats normally live outdoors under rocks, leaves and inside bird nests where heat and moisture are generated by the natural composting process. However, they are also known to reside in homes. Like silverfish, firebrats enjoy a humid environment, however they prefer much higher temperatures of 90°F and above. Consequently, they are discovered less, because they collect around furnaces in basements, water heaters in attics, inside fireplaces and within the insulation surrounding hot water pipes.

Silverfish and firebrats are mostly nocturnal, foraging at night. They prefer vegetable matter with a high carbohydrate and protein content. Indoors however, they will feed on almost anything, including dried meat, other insects, starch, paper, glue, sugar, molds, cereals and fabric containing cotton, linen, rayon and silk. They seldom damage fibers of animal origin such as wool or hair. These insects are hardy and can live without food for up to one year.

Silverfish and firebrats are considered pests because they consume and stain foods, fabric, books and wallpaper. Damage is manifested as yellowish stains and notched edges, although this is not usually observed. Molted scales and excrement are also left behind.


  1. Fabric, stacked paper products and cardboard boxes should not be stored for long periods.
  2. Spilled food must be cleared away.
  3. Reduce water availability by repairing leaky plumbing and installing adequate extraction fans to laundry and bathroom areas.
  4. Lowering the home’s relative humidity can be accomplished with dehumidifiers. Lighting a dark area is helpful as it forces the insects out of their shelter to new sites where they can be managed more easily.
  5. Outdoors, mulch should not be placed right up next to the house.
  6. Eradicating these insects can be difficult as they often reside between wall partitions, in insulation materials and in other protected places.

We can help! Contact us HERE at GreenShield Pest Control.

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