Silverfish 101: What It Is & What to Do With It


Finding a pest of any kind in your home can be nerve-racking, but the situation is even worse when you have an insect infestation. One insect homeowners are disgusted by (and may even seek out professional help to get rid of it) happens to be the silverfish.

Don’t be dazzled by their metallic appearance, as these insects are among the many superstars of the pest world. But there’s not much to worry about here, as preventing an infestation and even eliminating the silverfish doesn’t have to be tricky!

What Is Silverfish?

No, the silverfish isn’t a distant cousin to any fish you may have encountered so far, but the name does apply to the insect quite well due to its shiny flat teardrop-shaped body (usually metallic brown or silver).

The silverfish body is covered with slippery scales that serve as a form of protection while it’s out and about. Another similarity is how it moves; the insect is capable of slithering its way through your home in a fish-like manner.

But that’s where the similarities end and just the sight of the antennae is enough to identify this pest as a common (rather a primitive insect). But the wings are missing; throughout their very long history (the bugs have survived for millions of years), the silverfish have remained wingless.

A major noticeable feature (and one that would let you identify it more easily) is the tail; instead of one, this insect has three bristle-like tails. Typically, the bug is anywhere from 12 to 19 mm long (without the tail) and has two antennae and six legs.

Living Environment

Much like most house pests, the silverfish thrive in moist, humid environments. They are likely to make an appearance if the humidity inside the home is anywhere from 75 to 95 percent. Residential areas that fit those numbers are usually basements, attics, kitchens, and bathrooms.

silverfish inside house

The insects most often live in the crevices and cracks found in your floors and walls. Finding silverfish in pantries isn’t uncommon either, as they can feast themselves on their preferred foods, such as flour, sugar, and rolled oats. In essence, they prefer stuff that’s high in carbohydrates and protein.

Outside, the silverfish also seek out moist and humid environments, so expect to find them under tree bark, rocks, and moist leaf piles. Any objects that stop the ground from drying out can also become a safe harbor for this insect (tarps and toys, for example).

Mulch and weeded areas are rather attractive to them, too, like these, by default, indicate there’s some moisture around. And, of course, moist soil around your house — sometimes an indication of broken gutters — may as well serve as a bridge to your home.

Plus, in case of water damage, the wood on your house may soften due to water damage, making it chewy enough for the silverfish to go through it.

All the Harm the Silverfish Can Do to You

silverfish living

Image source: Flickr

The Insect Won’t Bite — But It Could Trigger an Allergic Reaction

Bites are common in insects, but fortunately, that isn’t something you should worry about here. The silverfish do have mandibles, but they aren’t strong enough to cause you any harm. Even if they tried to bite you, the mandibles wouldn’t puncture the skin, so they aren’t likely to transmit diseases either. In essence, the insect uses them to scrape food.

What these insects can do, however, is cause an allergic reaction. You can be allergic to silverfish droppings and skin. The bug’s exoskeleton contains tropomyosin, a type of protein, which can, in combination with some other allergens (dust mites, for instance), cause an allergic reaction. The symptoms include coughing, itching, and mucus buildup.

The Bugs May Attract Other Pests Too

Apart from causing allergic reactions, the silverfish may also attract some common pests, like carpet beetles. Though it’s not a huge fabric pest, a carpet beetle can still cause damage to items made of natural fibers (clothes and furnishings made from wool, silk, etc.), stuffed toys, bedding, and similar.

The silverfish may also attract insects that tend to prey on it, such as spiders, centipedes, and earwigs. Though these would potentially reduce the infestation, they can become another problem all on their own.

Material Damage Is the Worst Part, Though

Still, the worst kind of damage you could expect from the silverfish is that done to your belongings. Since the insect feeds on proteins and carbohydrates, it tends to destroy or contaminate various things found inside a home, including:

• Dry, starchy goods, such as flour, cereal, pasta, and similar
• Wallpaper glue
• Furniture
• Paint
• Books, paper, and photographs
• Insulation
• Clothing
• Carpets, curtains, tapestries, and bedding
• Dead insects
• Soap and shampoo
• Hair and dandruff
• Dust

Signs You Have Silverfish in Your Home

signs you have silverfish

Image source: Flickr

Since these are nocturnal (and rather fast!) creatures, you may not even get a chance to get a glimpse of the silverfish. The insects are shy and will hide when humans are around.

However, there are some telltale signs you may be dealing with an infestation. Obviously, you may discover these insects are your new roommates by finding feeding marks on furniture, clothing, and other items the silverfish love to feast on. Look for surface etchings, holes, and notches.

If you suspect there’s some silverfish nearby, there’s a chance you’ll also run into some scales and yellow stains. Other red flags include feces or droppings, which look like tiny pellets reminiscent of black pepper.

Why the Bugs Have Made Your Home Their New Habitat

why you have silverfish

Image source: Flickr

Unfortunately, much like most pests, the silverfish find their way into homes because they simply can. Most of the time, they may indicate water damage, which has caused your home to develop entry points moisture insects like the silverfish can easily use.

Once your home experiences water damage, algae, mold, mildew, and fungi may start growing, causing harm to your foundation and any wood you may have on or in your home. The erosion of the materials causes gaps to form. These can then be used by the silverfish to go into your home.

When it comes to choosing the outdoors or your home, the silverfish don’t dwell much on the decision. The insects follow the food path, and given there’s so much stuff they can eat inside a residential home — they may feel quite welcome.

Food is just one of the reasons they may stay; if your home is full of moisture and humidity, as well as dark corners they can easily hide in, the silverfish may decide to stay for longer. Since they can live up to eight years and reproduce fast, the damage is all but guaranteed in that case.

How to Find Silverfish in Your Home

This insect is probably faster than you, so even if you see one, you may not get to kill it. And even so, you won’t just have one insect in your home. There might be hundreds of them roaming about, most of which might have laid eggs in various cracks and crevices.

The telltale signs such as stains and droppings can indicate where the silverfish have been. They could be anywhere, though, especially if you have lots of moisture spots and clutter around. Thus, the best course of action is to try to get rid of them yourself (or hire a professional to do it). Then, simply follow some common-sense rules to keep them at bay forever.

Getting Rid of Silverfish on Your Own

Go For Chemicals in Case of Large Infestations

If there are no children or pets around, you may be able to eradicate the silverfish using some commercial insecticides. Granted, these may take a few weeks to offer some proper results, and they aren’t a guarantee your home will be a silverfish-free zone in the end. If you don’t remove the stuff that keeps attracting the insects (moisture, for instance), they can come back at any time.

If you opt for this solution, get a household spray formulated with pyrethroids such as tetramethrin, bifenthrin, phenothrin, and cyfluthrin, as well as synergized pyrethrin. The spray ought to be applied in crevices and dark corners and cracks (such as the ones you may have in your doors or window casings).

Any other dark hiding spaces should be treated as well. Make sure to spray some solution on bookcases and in closets, as well as on baseboards and walls (where the pipes are).

You should see some results in two to three weeks. If the silverfish are still wreaking havoc then, you’re most likely spraying the wrong areas or haven’t resolved the issues that have made the pests a problem. Moisture and water sources (drips and such) are just going to drive them back into your home.

In the same manner, you can use silverfish poison, though again, this isn’t the safest choice if you have pets or kids.

Use Repellents

Dispersing dried bay leaves around your home may discourage the silverfish, as the insects don’t like the smell. They also hate cinnamon, sage, and cloves, so you may try your luck with those too.

If you have some cedar shavings lying around, you can spread those around as well. Another option is to mix cedar oil with water in a spray bottle and tackle crevices and corners. You could also use a diffuser with the oil.

diatomaceous earth

Image source: Pinterest

If you have a small infestation to get rid of, sprinkle some diatomaceous earth (a type of white crumbly powder/sand containing fossilized algae) may help control the situation. The powder will dehydrate the insects and ultimately kill them. They do have to come in contact with it for that to happen. Still, it’s a much safer option for children and pets!

Place Sticky Traps

The silverfish may try crawling over those traps and consequently get stuck in them. However, think twice about using boric acid traps, as these can harm your furry friends and little ones.

Get Creative With Newspapers and Glass Containers

Since moisture attracts these insects, you can get rid of some of the insects by rolling and wetting newspapers. Once the silverfish make the paper their new home, throw it away or burn it.

Another (more ingenious) option is to get a glass container (a jar), wrap it outside with some tape, and then place something starchy inside. The outside “wrinkles” on the tape will let the insects crawl into the containers. However, they won’t get out due to the smooth glass interior.

Using commercial baits is another option. Still, they may not be effective since the bugs may not want to feed on them.

Prevention Techniques to Avoid an Infestation

Tackle the Outside of Your Home

Tackle the Outside

Keep your garden and backyard tidy by removing weeds and leaf piles and trimming vegetation close to your foundation to “burn the bridges” to your home. Essentially, get rid of damp debris to discourage the silverfish.

You can also move any construction materials and firewood (any wood, really) as far away from the house (and the ground) as possible. Additionally, if you’re using mulch, consider replacing it with crushed rock. It’s much drier and, therefore, unlikely to attract the pests.

You should also ensure water flows away from your home (and doesn’t erode the property) by grading your landscape. Remember to tackle downspouts and gutters as well, fixing any issues and keeping debris at bay.

Seal Any Openings, Inside and Outside

Get rid of cracks, holes, and gaps in your outer walls, foundation, behind and under baseboards, and in any other corners or crevices you can think of. Focus on the darkest (and usually most cluttered) areas, like the attic and the basement. But really, every unwanted opening should be promptly closed up.

Eliminate Dampness and Reduce Humidity

You can use a dehumidifier to make the inside of your home inhabitable for the silverfish. Ventilating rooms that easily get damp and warm (kitchen and bathrooms are notorious for this) should reduce the moisture too.

Get Rid Of the Clutter and Clean and Organize Your Home Regularly

The silverfish love dust and debris, so you should be tidying your home often to avoid an infestation. Make sure to vacuum thoroughly to remove any food bits and even suck up some silverfish eggs. Go over not only your floors and carpets but upholstered furniture too.

Since these insects prefer to hide from humans, remove any potential hiding spots (stacks of newspapers, dusty books, etc.). Consider eliminating anything that has adhesive on it, too, since the silverfish are drawn to it (cardboard boxes, wallpaper, and similar).

Finally, don’t leave out-of-season clothing in closets — pack it up and store somewhere dry that the silverfish won’t get into. Similarly, sort out your kitchen and pantry. Above all, make sure to keep food products (flour, pasta, pet treats, and similar) in airtight or glass containers.

Final Thoughts

No, a silverfish infestation doesn’t sound fun at all, but you now know how to tackle it properly without causing any further damage to your home or health. But remember — prevention is always the best option. Even if you don’t have some scaly bugs running around your home now, you might see them in the future if you keep your home untidy and full of cracks and holes!

Featured image source: Flickr

Nicole Middleton
Nicole calls herself a typical millennial girl and thrives on her share of social media, celebrity gossip, and all things viral content. She’s a big fan of pop music and plays the guitar as a hobby.