Life in Japan

6 Dangerous or Annoying Insects (and Other Pests) in Japan

If you’re planning to come to Japan in summer, there’s something you should know about first.
The crazy heat and humidity coupled with bad insulation of houses is one thing, but that climate causes another problem!
It’s the perfect environment for all sorts of creepy critters and other pests to grow and spread!

grasshopper in Japan

First, let’s have a look at the insects: There are many insects that I personally don’t mind or find rather cute, especially those that are similar to the ones I’m used to from back home.
Actually there are even some really beautiful insects as well, such as butterflies or the red dragonfly.

However, the majority of them is disgusting. And not only that!
The main reason why I wrote this blog post is to warn you! Some of them are dangerous and many tourists don’t even know about it! Some can hurt you badly, others can kill you! smilie
Although chances are low that it will happen to you, I think it’s important you have at least a rough idea of what to expect.

 

1. Suzumebachi – The Killer Hornet:

Suzumebachi (スズメバチ、雀蜂、胡蜂) which consists of the words “suzume” (sparrow) and “hachi” (bee, hornet) is better known in Western countries as Japanese giant hornet (Vespa mandarinia japonica).
THIS is my personal nightmare! Of course I’m afraid of a few insects and animals, but only bees, wasps and hornets cause me to panic!
And I’m talking about the relatively tiny European ones.
Now, this one is HUGE! And not only that, it can kill you! I’m not kidding! smilie
Obviously somebody who is allergic to the venom of bees will die from it. Suzumebachi’s venom is just so much stronger which is why it also can kill people who aren’t allergic to them, even adults, if the dose is sufficient. A significant number of people die every year in Japan because of this little monster.

My Japanese co-workers keep telling me that one sting doesn’t kill you, but the second time will, because by that time your body will show an allergic reaction. I’m not sure if that’s really true, but Japanese people keep telling me that.

Here’s a video where you can see a suzumebachi from close up. It’s really a huge monster!
(Note: It’s already dead, otherwise it would be too dangerous and stupid to do what that guy did!)

As most insects it’s active in summer, but you’re most likely to run into it in September and October. That’s also when I found one sitting on my bedsheets. But generally they can be around from May to November.

If you get stung, wash the wound with clear water, then try to get the poison out by squeezing. Don’t suck it out!
You should use a cream that contains “histamine”. After these frist-aid steps, go to a hospital or – if in the mountains – to a nearby mountain hut and get an antidote!

Those hornets can be very aggressive. Avoid wearing black clothes. If you have a dark hair color, then wear a bright-colored cap. Don’t use perfume!

One of the many bee-like insects in Japan.

This is probably a so-called “black suzumebachi” (クロスズメバチ), but I’m not sure. It’s always better to assume you’re facing something dangerous than the other way round, right?

There are many similar bee-like insects and all of them are huge! Even horseflies look similar if they’re just passing by. My strategy is to just run away instead of confirming what it is. That’s also the only strategy that kept me from being stung. Staying calm didn’t help! smilie

While it’s not very common that they invade your house (unless you live next to trees or they decided to have their nest under your roof), they’re still very present especially in rural areas of Japan. When traveling, be careful!

Warning sign of suzumebachi in Yumebutai, Awaji Island

If there are a lot of them around, you’ll find signs like this.
They suggest that you don’t make any hectic moves and slowly get some distance between you and the hornet.
“If you stay calm, they are not scary insects at all!!” – Yeah, right .. not gonna stay around to test if that’s true or not!

 

2. Mukade – Centipede

You’ll find a huge variety of centipedes in Japan, but one of them is especially dangerous:
Mukade (ムカデ、百足) is another giant creature in Japan, yet correctly spoken it’s not an insect.
In summer, especially after rainy season you might find them in your house or in your bed. smilie
You are most likely to see them if you live in the countryside close to mountains. They are very territorial, so just kicking them out, won’t help.
They would come back. I heard that many people pour boiling water on them and then cut them into half.

The following video has a lot of interesting information about the mukade:

The problem with this critter is that it’s very aggressive and it can bite you.
People often describe the pain as 10 times stronger than that of a common bee sting. Also the swelling on your skin can be quite bad.
In summer it’s very common for them to be all around the place outside, especially at night. I had a very unpleasant experience in Kyoto a few days ago which I posted on Facebook.

A centipede in Japan

There are a lot of other types of centipedes as well. This photo was taken near Gifu Castle in August 2010.

You don’t have to go to a hospital if you were bitten by a mukade, but it will hurt a lot, so it’s good to know what to do.
Go to a drug store and get something like “ムヒアルファEX“. It will help to cool the skin and release the pain a little.
Unfortunately there’s not much you can do to prevent them from invading your apartment. Japanese people tend to use this powder that is spread around the house, but it can’t guarantee that they will stay away!

 

3. Huntsman Spider:

You can take a deep breath now. This fellow is not dangerous, but it might freak you out nevertheless.
I’m not afraid of spiders, but when I saw my first huntsman spider I freaked out!
Their legspan can reach up to 30 cm!
Actually those spiders are not native to Japan, but have been accidentally imported! smilie
They do not have webs, but hunt their prey, often by jumping on it from above. They’re also very fast. That’s why they’re called “huntsman”.

Huntsman spider in Japan

The one in the photo was sitting on the wall outside of my apartment and even had an egg sac below its body.
A female spider can get aggressive when somebody tries to attack their eggs. Usually they are harmless, but bite if you provoke them.
The venom is not harmful to a healthy adult and usually there’s no need to go to a hospital after being bitten.

You’ll most likely run into them during rainy season as they look for shelter.
As scary as this spider might look, it’s actually useful because it eats cockroaches … probably the NUMBER 1 PEST in summer.

 

4. Cockroaches:

If you’re going to live in Japan, you need to know that you will have issues with these disgusting little guys! They are everywhere in summer. It doesn’t matter how clean or new your apartment is, they will come and pay you a visit!
Don’t freak out! If you see one in your apartment, get rid of it. It doesn’t necessarily mean you have a nest or anything.
As this is such a huge issue in Japan, you can easily buy traps and poison for cheap in most supermarkets and drug stores.
Very common are the “Hoi Hoi sticky traps” and the poisonous traps. A normal insect spray often doesn’t work well, so the “Goki Jetto spray” is the way to go.

In Germany you’ll only see roaches in very dirty places, so I was so shocked when I saw my first cockroach here in Japan. As I never had seen one before I wasn’t even sure if it was one at first.

 

5. Cicadas:

When thinking about insects in Japan, cicadas were always the first to come to my mind.
If you watch an anime that takes place in summer, you’ll surely always hear a buzzing sound in the background. When I was younger I thought that was some kind of machine, but it’s actually the cicadas!

Japanese cicada

Cicadas are quite big and some find them disgusting. I’m not a big fan of them, but I also don’t mind them.
Most of the time their buzzing is considered as a natural noise in summer and people find it relaxing to hear, but in some parts (e.g. parks) they can get so loud that it really hurts your ears! We’re talking about up to 120 dB! Technically that’s loud enough to cause permanent hearing loss in humans!

Other than the noise they are usually totally harmless for humans.

 

6. Other Pests besides insects

The following animals aren’t necessarily something you will run into when in Japan. It greatly depends on where you live and most tourists won’t even know they exist here. Yet I thought it would be interesting for people who intend to move to the Japanese countryside.

 

6.1. Frogs:

If you live in the Japanese countryside right next to rice fields, then from about May to August you’ll suddenly have extremely loud, croaking neighbors. The frogs are harmless and are actually a sign that the rice fields are in good condition.

Amagaeru, cute tiny frogs in Japan

The most common one is the so-called “amagaeru” (アマガエル, Japanese tree frog). It’s very tiny and I find them actually quite cute.
During the daytime they stay in the rice paddies, but at night they become active, hop near lights to catch the insects there.
That’s why I find some of them around my front door when I come home from work at night.
They’re actually quite useful and not a pest – apart from their noisy croaking at night.

 

6.2. Geckos:

To me personally geckos are not a pest at all. They are usually outside my windows at night to catch all the insects.
I find them rather cute and wouldn’t freak out if one of them comes into my apartment.

Geckos in Japan

However, some of you might find them disgusting and you have to know that they are VERY common in summer, especially in the countryside.
I see them every night! smilie

 

6.3. Mice:

Personally I have no experience with mice. I found a dead mouse in one of my cockroach(!) traps in late November!
They’re invading houses or apartments every now and then.
It’s especially likely to happen in the countryside and in old Japanese houses.
When you go into a drug store or a supermarket, you’ll find a lot of mice traps. That alone shows that it’s quite an issue in Japan.
Did you ever have issues with mice?

 

6.4. The Poisonous Snake “Habu”:

Japan doesn’t have that many poisonous animals. One of the most dangerous (as in: causing a lot of deaths per year) is the earlier mentioned “suzumebachi”.
Another really dangerous one is a poisonous snake called “Habu” (波布, Trimeresurus flavoviridis).
As far as I know they can mainly be found in Okinawa and it’s very unlikely that you’ll run into one.
While the venom is extremely strong, fatality rate is only 3%. If you are bitten, get medical treatment immediately.
In most cases you won’t die from the poison, but permanent disability can be caused in some cases.

 

6.5. Bats:

What? Bats? Well, to be honest this is more like a personal story, but I thought it might be good to share it nevertheless. I doubt that anybody will EVER run into the same problem, though.
Yes, Japan has bats – like many other countries, including my home country.
Moving to a really rural area, I suddenly had many of them around. I didn’t mind.

Until the first somehow made it into my apartment. I got the shock of my life! It was flapping around in panic, dropping poo all over the place. smilie
I opened the windows and waved my arms until it finally found its way out.
At first I thought it was a coincidence, but a few days later I had the next bat in.
After many sleepless nights and a lot of bat poo, I finally found out that they came in through the kitchen hood.
When I opened it, lots of poo fell out. After cleaning it thoroughly I literally had a mountain of poo in there. So disgusting.

A metal grid outside (outer kitchen hood) finally solved the problem. Now, I only find some bat poo on my car sometimes. smilie
Bats sometimes live in attics of old Japanese houses, but they’ll find other places to stay like in my case.
I think it’s important to know about that, although it really doesn’t seem to be very common.
Usually they are very shy, but they CAN bite and they COULD have rabies, so be careful!

 

Conclusion:

As you can see, being in Japan in summer can be a quite disgusting experience.
There are so many huge insects, but also many tiny flies and mosquitos. You’ll have mountains of dead insects in front of your door the next morning!

Especially for Japanese boys this is paradise, though. They buy huge nets to go insect hunting.
They’re particularly interested in all the big beetles. Japan has indeed a lot of them. There are also many insect museums all around Japan.
If you ever happen to visit Nagoya Castle, there is a nice exhibition of all sorts of insects in one of the floors:

Insects' exhibition in Nagoya Castle

I hope this blog post didn’t freak you out too much, but it is a fact that all these creepy critters are around and you should know about them.
I think it’s important to know which ones are dangerous and what to do when you encounter them – or how to get rid of them.
I couldn’t cover the topic in depth, but I hope I was able to give you a good overview.
And if you are actually fascinated by insects in Japan and want to see and read more about it, I can recommend this blog to you. smilie

 

There are so many creepy things out there, so let me know if you’ve ever run into something I didn’t mention here.
Please share your horror stories with us!
Were you ever bitten by a mukade or stung by a suzumebachi?

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117 Comments

  • *cries quietly* I can’t! I can’t do spiders! Even if they’re safe! 30cms??? I CANNOT! *cries some more*

    • No need to cry! As a tourist you probably won’t see any of those!
      But I totally understand. While I don’t mind spiders so much, it’s the size of this thing that makes me freak out! :(

  • Ihhhhh :stressed: Ich bin gerade so voller Ekel, dass ich kaum einen klaren Gedanken fassen kann, geschweige denn auf englisch!

    Es war mir schon vorher klar, dass es in Japan viele Insekten gibt und das sie, zumindest im Vergleich zu deutschen, echt riesig sind.
    Von den großen Hornissen hab ich schonmal gehört, aber ich wusste nicht, dass die wirklich so gefährlich sind. Als Kind wurde mir auch hier schon eingebläut nicht in die Nähe von Hornissen zu gehen, weil es einem hinterher ziemlich schlecht geht und man auch sterben kann D:
    Von den Kakerlaken hört man ja viel und damit hab ich mich so gut es geht schon abgefunden, aber die Riesenspinnen?!?! Und hartnäckige Tausendfüßler?! :whyohwhy:
    Ich glaub, ich werde in Japan, zumindest im Sommer, nur eingehüllt in Moskitonetzen oder evtl im Imkeranzug rumlaufen XD Ich bin leider gottes ziemlich panisch wenn es Insekten angeht :disappointed:

    Ic hab gehört, es kommt auch durchaus mal vor, dass sich (riesige) Gottesanbeter in die Wohnung verirren. Hattest du auch damit schonmal Probleme? :sweatdrop2:

    • Ich habe Gottesanbeterinnen schon ein paar mal gesehen. Sehr faszinierende Tierchen! Die stören mich eigentlich nicht! :)
      In der Wohnung hatte ich sowas noch nicht.

  • I’m forced to be afraid of wasps as i used to be close to death everytime when bitten. This is not good news. I wasn’t aware of the real danger of Suzumebachi :whyohwhy:. I don’t mind insects in general tho. In Germany we’re more affected by man-made dangers then natural dangers i guess ;)

  • Moving to Okinawa soon. I thought insects were terrible and huge here in the US. I’m so mistaken. The bees and wasps and centipedes sound horrific. Plus roaches are just intolerable. Not to mention the snakes. Thank you for writing this. It was helpful to know what I should look forward to.

    • I visited Okinawa a few months ago and locals there told me there are no suzumebachi (= the huge killer hornets) in Okinawa, so maybe you’ll be lucky! ;)

  • Oh. Rabies via bats also exist in Japan. New for me.
    Its a weired disease. Have 2 people suffering by rabies in my critical care unit in germany.
    1 st infected by dogs in tunesia I send to the centre of tropical medicine in Hamburg. Death after 2 weeks. 2nd a japanese coworker returned from holiday in Bali we give an experimental treatment with high dose barbiturate anesthesia. But also death after some weeks.

  • When I was living in Japan 2007/08 I had several experiences with the insects listed above, too! I saw a very huge and long Centipede once in the institution I worked for. It was moving towards the dining room. I could take a picture and it is still fun to show it to friends and co!
    By the way… in the big dining room, if you went to it by night time and you turned on the light, you could see HUNDREDS of coackroaches suddenly running away into their secret places… :huh: interesting was: the first time you saw it, you were like “omg”, but few weeks later you were so used to it, that you didn’t notice them anymore :sweatdrop2:
    But when I see your Spider Picture…. omg that freaks me so out >_< that's the most horrible thing! :sweatdrop2:

    • At least the spiders are harmless, but they’re just so freaking big! (T___T) ….

      We had roaches coming out during daytime at work last year. I guess there were so many that they even came out in bright daylight. Eww!! :(
      I can never get used to them. So disgusting!

  • I’m going to move to Japan with my family.
    But i never thought that such insects can be found in japan. :sweatdrop:
    I wish they won’t come to our apartment. :D
    Can i find the Hornet or Mukade in tokyo or uji too? ~
    As i see the Picture i became freaky!
    (Uji,宇治市 is located very near of Kyoto. In the South Direction -10 minutes to the central of Kyoto by a local train.)
    (Hachioji,八王子市 is located in the central part of tokyo prefecture. 1 hour with local train to tokyo central.)
    I guess/wish i won’t find them in the central of tokyo or in other cities like Chiba,Yokohama etc.

    • Hello Justin!
      Thanks for describing where the locations are, but of course I know them. I’ve been there before. ;P
      In general, you could find them EVERYWHERE! Especially in Kyoto I’ve seen a lot of mukade, even in Central Kyoto. Kyoto has a lot of mountains and when you live close to mountains, you’re more likely to run into them.
      I’ve seen killer hornets in Tokyo. You need to move to Okinawa or to one of the small Izu Islands outside of Tokyo if you want to avoid them.

      It’s sometimes really difficult to predict if you’ll run into certain insects or not.
      Just as an example: I used to live about 2mins away from a co-worker. She got a lot of mukade in her apartment, but I didn’t see a single one in 4 years! We both didn’t live in the first floor!

      Good luck to you and your family.
      I wouldn’t worry too much about it! :D

  • Out of all the things that worry me about visiting (or living) in Japan this post has scared me the most. Mostly because it seems that they put all the insects that creep me out the most in one country. I was literally hiding behind some of my hair while scrolling down haha. :whyohwhy:

    • Haha, I’m sorry. :hihi:
      However, I think it’s better to know beforehand what you can expect here in Japan.
      There are several measures you can take to protect yourself and your apartment as much as possible, but you’ll never be able to shut them out completely! ^__^;

      • Actually my mother lives In Osaka and she called a company and they bug proofed the house so whenever I visit I rarely see any bugs :shiawase: Especially spiders and centipedes :hum: I cry like a little girl when I see them and I’m in my 20’s :disappointed:

        • Guess that’s a good solution if you want to make sure there are no creepy crawlers left, although I’d also be a bit afraid of all the remaining chemicals in the house.

  • I found this post while looking up Japanese bee species and found it very informative!

    I lived in Kumamoto myself during 2010/2011, and had some nice and less nice experiences with insects during that time. Luckily I never came across a huntsman spider! Holy shit those things are massive! :stressed: I would have definitely totally freaked out, I don’t have arachnophobia but I’m not a big fan of spiders either. Where I lived we mostly had a species that was maybe 10-15 cms with legs, it liked to build nests up in trees and on telephone poles and such and fortunately wasn’t very interested in coming inside. Never got a centipede inside, either (thank god!), though I saw a few outside.

    Roaches are of course an experience nobody can get around. :notamused: I’m quite disgusted and not a little terrified by the things; I would be a bit embarrassed if I hadn’t seen quite a few Japanese flip out just as much about them. Tip in the summer: Be sure to air out your shoes sufficiently or use antibacterial spray. If they get too smelly it’s not only embarrassing for you, but also Roaches think you smell interesting and will try to climb inside your shoe. Even if you are wearing it at the time. I kid you not. :disappointed:

    Did you have any praying mantises where you lived? We had quite a few of them in late summer, they mostly just sat around calmly and didn’t pay us any attention, we could even walk up to them and take a closer look. We thought they were quite interesting; the females were a bright green colour, and if you waved a finger in front of their faces you could see their eyes following your finger! So cute! :D

    I wonder what Japanese visitors to Europe think of all the insects they encounter over here? A friend recently told me of an experience with an exchange student, they were walking around outside and came across a bumblebee. My friend had to calm the poor girl down and was apparently stared at in horror when she explained that most Germans find bumblebees quite cute. :happy: She tried to explain the differences between bees, hornets, wasps and bumblebees, but since the Japanese only know “hachi” and neither my friend’s Japanese skills nor the German/English skills of the exchange student were all that good, it proved to be an exercise in futility.

    • Hi Luthien!

      Thanks so much for sharing your experience with us.
      Yes, I’ve seen a praying mantis here and there, but not near my apartment. I love them!

      I don’t find bumblebees cute to be honest. I just run away from anything that flies and is black and yellow – just to be safe!
      And in Japan where one of those can actually kill you, it’s just normal to freak out whenever you see something big like that.
      In Japan there’s also a bee called “kumabachi” (carpenter bee). They’re huge and fat, but they’re not dangerous at all. When I saw my first, I ran away screaming. *g*

  • Hi. Love the page. Not at all dangerous, but the butterflies are pretty huge too – those black ones look like birds at a glance. One thing I was curious about was the western identity of bata. They’re all green, look a bit like crickets, but make no noise – well not as I’m aware anyways – but some little critter is eating all the plants in my garden and I only ever see bata.

    • I love those huge butterflies! They’re so beautiful, but too fast for me to take good photos of them. *g*

      I don’t have a garden myself, so I can only guess, but I know that snails and caterpillars are a huge problem for some gardens here in Japan!
      I don’t know about grasshoppers and the likes.

  • I’m so glad I found your post!
    I know this is just silliness, but one thing that always puts me off in living in Japan is the countless bugs/insects/pests stories, and especially the MUKADE!
    I’ve had bad experiences with roaches before (literally I lived in the states for a month) where little ones would be everywhere and even inside the phone!!! *shudder*
    What do you think of places like Sapporo or in the island of Hokkaido where colder weather means less bugs? Is that logical to assume that? I’m also thinking in big cities like Tokyo, Osaka, there will be less of them??
    I was traveling in Koyasan during my vacation, and stupidly, I’ve worn shorts!!! (the Japanese guy in front of me is wearing all sorts of protective gear) The whole trip was less enjoyable when all kind of bugs want to climb onto my hairy legs….

    • Hey Lars!
      Sorry for the super late reply. :sweatdrop:

      What, wait, inside the PHONE??!!?? (O__O”) ….

      There are less insects and the “insect season” is also shorter in cold places such as Hokkaido. However, there are far more insects in big cities than you’d expect. It might be better than in the countryside where I live, but you’ll run into roaches and other creepy things in big cities as well, I fear. T___T

  • Hey! this is the first time i step into your blog, i was looking for dangerous insects in japan (i’ve run with a little insect today twice, like a wasp, very tiny but very red, so i was wondering if it was dangerous haha
    i liked this post, and i want to enrich it!, in the area of CHIBA, near te beach, is whole countryside, and ive found to be surrounded by the biggest plague of dam spiders! (i saw lots of that big badass spider u mentioned on ur post, and for me (i’m mexican) we have spiders but they are tiny (but dangerous as hell) and i was just wordless, but my friends didn’t allowed me to terminate spiders, they said these are great against cockroaches, exactly as u said here) but this ones were from many colors, green, yellow, etc, they are everywhere, every corner u see webs with a big mofo in the center haha
    now i’m in fussa, tokyo, no more spiders, i hate them all xD, i have just moved here so, most things are new for me haha

    keep the good vibe!

    • Hi Mario! :)

      I’m really not a big fan of big(ger) spiders. We have those black and yellow striped ones everywhere here right now, but luckily they’re all outside.
      I’ve never found any of them inside thus far.

  • I do not do well with hornets. I’m ok with honeybees. Spiders I’m ok with since they eat mosquitoes but I just like it better when they stay where I can see them =)

    • As long as all of them stay far away from me I don’t mind them at all.
      Problem is, usually they don’t.
      And especially those nasty hornets are aggressive and will follow you around! :(

  • So, I just got out a tape measure to see what 30cm actually looks like, and I’m starting to feel a bit sick! How does a spider get to be that big? Usually when I find a spider in my house I catch it in a glass and, if I’m feeling brave enough, throw it outside, if not, just leave it and pretend its not there or get someone else to do it for me. I don’t have a glass with a 30cm circumference! And I’m not sure I’d want to risk one of those coming back inside. What do you do if one gets in your house/apartment? (I’d also like to get my hands on whoever accidentally imported those!)

    • I’m sure there are various ways.
      If you’re brave enough try to catch it with an insect net and thow it out / take it away far enough from your apartment.
      Luckily I never had one of these inside of my apartment, but we had one at work. Eventually we sprayed it until it stopped moving (be careful, it takes a while). But you can’t stay in the room afterwards for several hours and make sure to ventilate the room well.

  • I’m a ole texas cowboy born an bred . Every thing in texas is BIG………But you get use to these critters…They all have a purpose …….just like us………We all need to live in harmony with the earth and its folks……..So don’t be scared………..Growing up in the country you learn a lot about nature and her balance…Don’t worry ……These critters have a purpose……..Just like us…….

    • I know that some have a purpose which makes it a bit easier, but doesn’t change the fact that personally I’m either afraid or find them disgusting.
      And I still haven’t figured out the purpose of those damn killer hornets. :(