Are Silverfish Harmful? 16 Silverfish Facts Everyone Should Know

One of the first questions people ask when they’ve spotted one of these slithery bugs is: are silverfish harmful?

It makes sense why.

We’re used to pests that bite, steal our blood, and spread bacteria and disease while at it. And these silverfish, with their long creepy antennae, look like they could be dangerous. So are they?

Let’s dive in. Here are the most important silverfish facts everyone should know.

Are silverfish poisonous?

No. Silverfish may be gross-looking but thankfully, they’re not poisonous.

Often, due to their appearance, silverfish can be mistaken for some more venomous strains of centipedes, some of which can be a danger or risk to humans if they bite.

>>>What Do Silverfish Look Like? 6 Bugs That Look Like Silverfish

It’s important that you learn to tell them apart for precisely this reason.

Do silverfish crawl in your ears?

Of all the strange silverfish tales that abound, this one is the strangest: that silverfish will crawl in your ears. And even worse, lay eggs there.

But is it true?

While this claim is widely regarded as unfounded, there have been reported cases of silverfish hanging out in people’s ears like this disturbing encounter and this horrible experience.

So while it is rare and very unlikely to happen, well, it can happen.

Do silverfish bite?

Silverfish tend to be quite reticent around humans and would much prefer to run away like a pansy than stay and fight their corner, so they generally don’t bite humans.

>>>Do Silverfish Bite? The Truth About Silverfish Bites

That’s not to say that silverfish bites haven’t been reported in the past, however. A few unfortunate souls have experienced silverfish bites but the good news is that they’re harmless.

Should one manage to sink its gnashers in to your hand or elsewhere, it’s not a cause for concern unless you’re allergic. It may sting a little and perhaps show up as red or tender, but you’re unlikely to suffer any other side effects or risks.

Do silverfish make noise?

A silverfish infestation can make infinitesimally small noises as they gnaw away on thing like cardboard and the glue on wallpaper. But unless you have super-powered hearing, you most likely won’t notice it.

Especially since silverfish are nocturnal and creep about during the hours you’re most likely to be asleep.

If you hear scratching or rustling noises, it’s most likely not silverfish that are causing it. It can be rodents. If it’s a hissing noise, it’s likely to be cockroaches. In which case, you have bigger fish to fry. Sorry to be the bearer of bad news.

Are silverfish harmful?

Luckily for us, silverfish aren’t actually harmful to humans or pets, aside from the initial visceral shock or fear of stumbling across one, that is.

So if they don’t feast on you and your loved ones, do silverfish pose any other dangers?

Well, that depends.

Silverfish can’t sting you like a wasp or bite you like a mosquito. They don’t make disturbing noises. They also do not carry diseases and, despite how common they might seem at times, are quite reluctant and shy critters.

As such, they have little interest in crawling in your ears while you sleep. In fact, they have very little interest in people at all. Rude, I know. But at least you don’t need to worry about them hurting you or your family or spreading disease.

That doesn’t mean they’re harmless though. Silverfish may not be dangerous for you but they can wreak havoc on your belongings. How? It all comes down to their eating habits.

What do silverfish eat?

Silverfish love carbs. Starchy foods rich in carbohydrates and cellulose are a silverfish’s favorite foods. This is why silverfish are often found in pantries, feeding on everything from cereal to dry pet food, as well as the paper packaging these dry items are wrapped in.

>>>What Do Silverfish Eat? Do Silverfish Eat Clothes? Wood? Us?

They also have a deep abiding love for sugars and protein, which is why silverfish will also get into your sugar and coffee. Silverfish also have the ungracious habit of feeding on dead skin cells cast off by humans and pets.

The adventurous eating doesn’t stop there. Silverfish feed on glue, wallpaper paste, linen, silk and other natural materials. In short, they are not picky eaters at all.

When in dire straits, silverfish will even resort to eating dead insects. Which may prompt you to ask a couple hopeful questions, like:

Do silverfish eat spiders? Perhaps, but only if the spider is already dead. Silverfish aren’t predators and in a battle of spider vs silverfish, the spider will end up eating the silverfish every time.

Do silverfish eat roaches? Again, only if the roach in question is completely dead. It’s unlikely to happen otherwise since silverfish are completely defenseless. In a battle of roach vs silverfish, roaches will end up victorious with a silverfish snack.

So, as you can see, silverfish aren’t going to help you get rid of any of your other pest problems. If anything, they will contribute to it by being a helpless food source.

In the meantime, they will be causing untold damage themselves…

What do silverfish do?

A lot of people ask this question, seeing as silverfish can start to seem like fairly magnanimous creatures that don’t pose much of a threat or disturbance. I mean, they essentially eat, hide and hang out.

So apart from just existing, what do silverfish do?

Simple. Silverfish cause damage. Here’s how.

Do silverfish eat paper?

Silverfish will absolutely eat paper, mainly because paper is composed mostly of cellulose, a silverfish favorite. Their habit of eating cellulose means they can destroy books, photos, newspapers and other documents.

So that box of old photos in your closet that can’t be replaced? That’s like a silverfish buffet.

Do silverfish eat books?

Absolutely. Books are among the silverfish’s most favorite foods. Paper is anywhere between 90% to 97% cellulose so it’s as delicious as can be to a silverfish.

Do silverfish eat clothes?

It’s not their first choice but silverfish will eat natural fibers like cotton, linen, silk and even leather. So if you have a lot of nice clothes, silverfish could be your worst nightmare.

Do silverfish eat wool?

Silverfish don’t necessarily like the taste of fabrics. They prefer to munch on clothes for the spills and stains that are embedded in the fabrics, i.e. sugary stains and starched fabrics.

Wool is not off-limits to a silverfish but if you’re noticing significant damage to your woolen fabrics, it’s most likely another culprit, like clothes moths or carpet beetles.

Do silverfish eat money?

The cash money issued by the Federal Reserve aren’t actually made of paper. Instead, they are a blend of 75% cotton and 25% linen. So yes, silverfish can eat money. If you have a silverfish infestation, don’t leave your cash out uncovered.

Do silverfish eat wood?

One thing that silverfish aren’t known to eat is wood. So if you notice damage to your wooden furniture or floors, you may another pest problem on your hands like termites or carpenter ants.

That being said, silverfish may hide and live in tiny cracks and crevices found in wood, making these gaps bigger in the process. That can result in damage to your wooden possessions.

Do silverfish eat glue?

Yes, silverfish are well known for munching on the glue that binds books together. The starch that’s found in glue is the main attraction.

And if you have wallpaper, silverfish love to get in behind it and eat the paste that holds it to the wall. So you could be minding your own business in your living room one day and have a sheet of wallpaper peel right off the wall and land on you. It’s not life threatening, but it’s definitely going to annoy you.

Can silverfish fly?

You may have spotted a silverfish high up on your walls or even your ceiling. Which leads you to ask: can silverfish fly? Do silverfish have wings?

No. And no.

Silverfish don’t have wings and they cannot fly at all.

Do silverfish jump?

Silverfish may be fast but they certainly can’t jump. In fact, the main thing that a silverfish has going for it is that it can run very fast. So in most cases, silverfish rely solely upon their cross-country running prowess. If you’ve ever experienced a silverfish first hand, you know what I mean. They’re lightning quick when they need to be.

And if you spot something that looks like a silverfish but jumps – it’s not a silverfish. Most likely, it’s a jumping bristletail.

Can silverfish climb walls?

Silverfish are flightless bugs but they are decent climbers, demonstrating much of the wall-climbing skill displayed by their other creepy crawly counterparts like spiders, beetles, and some scorpions.

So if you spot a silverfish high up on your wall, you know how it got there.

Do silverfish leave a silver trail?

Of all the strange silverfish myths, this one takes the cake. Silverfish, despite their name, do not leave silvery trails. Instead, they get their name from the fact that they tend to have a silvery grey color.

Silverfish actually don’t leave a sort of trail, per se. Instead, they can leave behind small yellow spots in places that they’ve infested.

If you’re finding silvery trails around the house, the culprit is not a silverfish – it’s likely to be a slug. Slugs ooze a slimy, silver trail behind them as they move.

Do silverfish come from drains?

Silverfish love places with high humidity and plenty of moisture. That’s why they’re so commonly found living in bathrooms.

But silverfish simply like to hang out near drains, sinks, pipes, and floor grates for the moistness these spots provide. They don’t actually come from drains.

So if silverfish aren’t coming into your home from the drains, where are they coming from?

>>>What Attracts Silverfish? 6 Common Causes of Silverfish

I found one silverfish, are there more?

You’ve found one silverfish. And now you’re wondering: are there more? Do silverfish come in groups?

Silverfish don’t necessarily travel in groups or even pairs. They don’t have the sophistication to have developed a buddy system.

So you’ll most likely only spot one silverfish at a time. But there’s good reason why seeing even one silverfish is the gold standard of silverfish infestation signs.

>>>6 Subtle Silverfish Infestation Signs that Spell Trouble

If you’ve seen one, it’s very likely to be the case that its family and friends are lurking nearby. Here’s why…

Do silverfish lay eggs?

Oh, do they! Silverfish not only lay eggs – they lay them in bulk.

As soon as a female silverfish reaches maturity, she can lay eggs every day until the day she dies. In her lifetime, that can add up to more than 100 eggs deposited in small cracks and crevices around your home.

But wait. It gets worse. Once a silverfish has found a safe nook or cranny to lay eggs in, she can also emit aggregation pheromones to let other silverfish know that there is a lovely delivery ward nearby. This prompts other silverfish to join and lay more eggs.

The crowding caused creates the ideal temperature and humidity for these eggs to develop and hatch.

How do silverfish mate?

Of course, in order to make silverfish babies, silverfish need to do some breeding. So how do they get it on, so to speak?

In terms of the actual mating process, silverfish sound more like shy pre-schoolers with a crush than any sort of serious life form trying to keep its existence relevant.

Silverfish fall into a small dance or ritual during reproduction which can take around half an hour (show offs) and is divided into three distinct phases…

  • The first phase is characterized by the male and female facing one another off and rubbing their antennae against each other’s – after a while, they begin to back off and then return to this position, like playing the lowest stakes game of chicken known to man.
  • The second phase sees the male fleeing from the chasing female…your guess is as good as mine.
  • In the third and final phase, the two lovers stand side by side, whilst the male vibrates his tail against the female, laying sperm capsules which the female absorbs into her body and fertilizes herself with.

Coming soon to a theatre near you, the rom-com for the ages.

How long do silverfish live?

We get it. This species is vile. But you don’t want to get your hands dirty and you’re hoping that maybe you can just wait for them to die out.

Once they’ve reached maturity, though, a healthy silverfish living in ideal conditions can last an average two to eight years, with ample opportunity to mate and procreate in that timespan. A worrying proposition for anybody with an infestation.

How can I get rid of silverfish?

And now we come to the end of our silverfish roadmap. With any luck, you’ll now be better informed when it comes to ridding your home of the silver non-fish that’s been chewing all your books.

But how do you do it?

The question of silverfish damage and the lengths you should go to to rid yourself of them is pretty subjective.

Some folk might not care if they have to squish (or rather, hopelessly chase) the odd silverfish, but a lot of homeowners find themselves googling emigration laws for tamer countries at the first sight of antennae…or so I hear.

If you’re in the latter camp, you’ll want to check out our full, extensive guide to get rid of silverfish permanently.

>>>How to Get Rid of Silverfish Once and For All in 7 Easy Steps

And don’t worry. This problem can be solved. Silverfish are gross, but they’re not worth making yourself sick over.

If you have silverfish, try not to panic. Just remember that they can’t hurt you or your family. Unless you’re made of paper and glue. In which case, you may have bigger problems. 

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