Biology & Reproduction
Silverfish are easily recognizable because of their distinct shape and color. Their body is shaped almost like a teardrop and is covered with silver-colored scales. It has long, thin antennas and similar looking appendages on the back. One species of silverfish has dark lines along its entire body. Silverfish are found throughout the United States and the world. Breeding can take place anywhere in the structure, such as wall voids, attics, under or inside subflooring, and more. Shake roofs are especially excellent breeding sites during warm weather months because they contain a lot of moisture and food supplies. The silverfish female will lay about 1-3 eggs every day and will place them in cracks, underneath objects, or she may even leave them exposed. Depending on the environment it’s placed in, developmental time from egg to adult can take either 3-4 months in favorable conditions or 2-3 years otherwise. The typical lifespan of a silverfish is roughly 3 years.
Habits – Silverfish habits depend on the species.
Fourlined silverfish can be found outdoors among mulch of flower and shrubbery beds. They gray silverfish will not be found outdoors, but rather inside homes and commercial buildings. All species of silverfish will hide during the day and will rest in tight cracks or crevices. They can live anywhere in the house they prefer though. The most common commercial buildings silverfish have been located are offices and libraries. Silverfish can easily enter a home through a shake roof, and people will notice them when they come down through skylights and light fixtures in the ceiling. Sometimes silverfish will live in cardboard boxes of books and paper, and be brought inside that way. They are paper pests and will be found amongst wallpaper, book bindings, envelopes, and other paper sources. They also prefer areas with high humidity and temperatures. However, the four-lined silverfish is not constrained by preferences of moisture and temperature. Silverfish are especially good climbers.
Silverfish prefer proteins to carbohydrates, such as dried beef. They also will eat their own dead or injured. Gray silverfish will eat proteins and carbohydrates from both plants and animals. They’ll also eat artificial silk, linen, rayon, and cotton.
There are signs to look for if there’s a silverfish infestation in your home. They leave feeding marks and are irregular. The marks range from holes, notches along an edge, or surface etchings. They also leave yellow stains, scales, and feces (tiny black pepper-like pellets) that can be seen on materials. Since silverfish are such good climbers, anything stored against the house such as woodpiles or cardboard must be removed, as they can climb up them and get through the windows and doors and into the interior. Because silverfish species range in preferences, it takes extensive pest control knowledge to treat an infestation. Any do-it-yourself methods will be costly and ineffective. If you notice the signs of silverfish, call a professional pest control company.