SILVERFISH APPEARANCE, BIOLOGY, HABITS, CONTROL RECOMMENDATIONS
Click on image to enlarge
Silverfish Photograph by: J.L. Castner, University of Florida
1/2 inch long, with a uniform silvery color over the upper surface. Their
bodies are long and slender, flattened. The bodies are broad at the front,
and gradually tapering toward the rear.
They can be found almost anywhere, but prefer damp, moderate temperature
places such as basements, laundry rooms, and under sinks.
Silverfish Biology and Habits
- Silverfish prefer a dark, moist environment and require
a large supply of starchy foods or molds.
- Silverfish are considered to be nuisance pests that can feed on wallpaper
pastes, natural textiles, books, and papers.
- Silverfish also feed on mold or fungi that can grow on various surfaces.
- They are fast-moving and can travel throughout buildings.
Once silverfish find a good source of food, however, they stay close
- Silverfish go through only a three stage life cycle called gradual
metamorphosis, while many insects have a four stage life cycle (complete
Silverfish may lay eggs at any time during the year, and take 19-43
days to hatch.
The life cycle from silverfish egg to adult is three to four months.
They prefer humid areas (75 to 97% humidity), like bathrooms and moderate
temperatures (70o to 80o F).
- Silverfish are found in basements, kitchens, sinks, bathtubs, in
bookcases, on closet shelves, behind baseboards, wallpaper, window or
door frames, wall voids, and sub-floor areas.
- Silverfish are active at night or
are active in dark places found throughout the structure.
Silverfish can be a problem year round.
Attics are a favorite place for silverfish due
to the abundant food sources due to the recycled blown in paper insulation
and storage boxes.
You may see silverfish trapped in sinks and bathtubs because they enter
seeking moisture and are unable to climb a slick vertical surface to escape.
and Damage of Silverfish:
are found in basements, kitchens, sinks, bathtubs, in bookcases, on
closet shelves, behind baseboards, wallpaper, window or door frames,
wall voids, and sub-floor areas.
they molt during their adult lives their cast skins may be a useful
diets are high in protein, sugar, or starch, including cereals,
moist wheat flour, starch in book bindings, and paper on which there
is glue or paste.
can damage book bindings, wallpaper, paper goods and dry foods. They
may eat holes, irregular shaped in the wallpaper to get to the paste.
Silverfish may bite very small holes in various fabrics, including cotton,
linen, and silk, even though they cannot digest either linen or cotton.
Firebrats will feed extensively on rayon, whereas silverfish usually
damage it only slightly.
- They may
leave a yellowish stain on fabric.
they may be found in nest of insects, birds, mammals, and under tree
bark and mulch.
They can be found in wood shingles or sidings on houses, they may enter
the home from these.
RECOMMENDED MEASURES FOR SILVERFISH
CONTROL: How to Get Rid of and Kill Silverfish
- Sources of any undue moisture, such as faulty plumbing
or condensation that provide the humidity favored by these pests should
- Dehumidifying reduces the moisture content of the
air that these insects find essential. Some methods for dehumidifying
Mend leaking pipes.
Ventilate closed rooms and attics.
Eliminate standing water.
Use a dehumidifier an air conditioner.
- Regularly vacuuming cracks and crevices with a narrow vacuum tip
also can be a good method to physically remove these insects from their
- Removal of food sources , stored in tight containers.
- If you have a problem of silverfish inside your home, a good
residual perimeter treatment of:
These residual insecticides, sprayed around entry points and foundation
of the house would be the first step.
Spray along the foundational wall, with a two or three foot band.
D-Fense SC, Demon WP/Cyper WP :
last for two to three months.
All these products are odorless. The wettable powder (WP) formulation
in the Demon WP and Cyper WP will leave a slight film that can be seen
against dark surfaces. The Cyonara 9.7 does
not leave a film.
However if you have a more severe problem with silverfish , look
into stored boxes and the insulation in your attic. It is best to
dust or bait these areas for greater control.
When you use baits or dusts, you do want to get it as close as possible
to their habitats to be effective.
You never want to bait and dust in areas that are visible.
Dust needs to be in hidden areas such as :
Behind Refrigerators and Ovens
Under siding .
- Recommended dusts for silverfish control would be: Cimexa Dust
D Fense Dust
Both dust last 6 months in the attic area or recessed area.
Apply it in the attic
in the insulation area in particular, under siding, in storage boxes,light
fixtures, electrical outlets.
Apply it to areas that can be kept dry. An easy way to apply D Fense Dust or Cimexa Dust, if broadcasting in the insulation area would be the use of a duster
called the Dustin Mizer,cranking out a large amount of dust at a time.
You will want one lb. of dust per 800-1000 sq. ft.
For smaller dust jobs Bellows Duster would work fine.
- Another very effective way is the use of baits in the attic or on
the outside for silverfish control.
- . Intice Granular Bait works very well
against silverfish as well as roaches and crickets.
It can be sprinkled out in a self contained one lb. bag, in all the
areas you believe they are hiding.
- You can also you a residual aerosol like
D-Force HPX Aerosol
with a crack and crevice tip, enabling you to get behind baseboards
and corners of traveling paths of the silverfish. This type of aerosol
is very helpful in bathrooms where silverfish like to eat the back
Silverfish Paks are designed to go inside. These Paks destroy these
year-round pests that eat wool, paper, linen and cellulose materials.
Place odorless, wafer-thin packets under rugs, behind curtains, in closets
and dark hidden places . Place away from children and pets. Niban/Intice
and Silverfish Paks both are designed to attract the silverfish as they
eat, functioning as long term baits.
If you do not know the exact location of
the habitat of the silverfish and cannot treat it directly, baits are
ideal for silverfish control.
*** Silverfish Paks is an excellent product to
accompany a through spraying and/or dusting.
It is not advised as a stand alone treatment.