My Kabuto Mushi Dream
My dream, when moving to Japan, was to keep a Japanese rhinoceros beetle, known here as “kabutomushi” (which means, “helmet bug”). Unfortunately, I couldn’t find many resources in English on how to take care of rhino beetles (also known as Hercules beetles). So, for at least my own benefit, here’s some information about rhinoceros beetle care that I’ve found from Japanese websites.
I hope this is helpful to everyone who is looking for information about keeping a rhinoceros beetle pet.
Rhinoceros Beetle Care
Rhinoceros Beetle Materials
Breeding case (Japanese: shiiku case)
A breeding case is Just a normal animal aquarium, like what’s used for hermit crabs. They are usually plastic and cube-shaped. Be sure it is a type that will keep the air inside humid.
Bug bedding (konchuu matto)
Bug bedding (konchuu matto): If not planning to breed beetles, many types of bug bedding are okay. For ease, many websites recommend store-bought beetle-specific bedding.
In addition to basic bedding, beetles also like leaves, logs, etc., all of which can be bought at the store.
Decaying branches (kuchiki) and leaves
Store-bought branches marketed toward beetle-keepers or branches from outside are okay. The branches give the beetles places to hide.
Food dishes (esazara)
Food dishes keep the beetle jelly from spilling onto the bedding.
Food (esa)
You can buy special beetle jelly (konchuu zerii), in appetizing flavors such as black sugar, “protein,” and fruit (yum!). Apparently, bananas are also good for rhinoceros beetles. Even though it’s traditional beetle food in Japan, avoid watermelons and other water-heavy fruits.
Beetle humidifier (kirifuki)
Rhinoceros beetles are very susceptible to drying out, so this spray, or, alternatively a sort of “water bottle,” helps keep their bedding moist. Also, putting leaves in the case helps keep the soil moist.
Where to Buy Materials
Most of the above materials can be bought at home-and-garden stores, such as Cainz, or 100 yen shops.
Rhinoceros Beetle Care Instructions
Purchasing Necessary Items
In Japan, some home and garden centers sell rhinoceros beetles. I bought my beetle at a Toys’R’Us. Typically, it’s much easier to find them in stores in summer.
The normal price is from 300 yen to 2,000 yen. I’ve been told kids really enjoy catching wild beetles, but I’ve also heard the wild beetle population has been dwindling because of loss of habitat.
Preparing the Case
Fill the case 1/3 of the way with bedding that has been moistened with the humidifying liquid or plain water. Make sure the bedding is moistened to the point that it doesn’t crumble apart in your hands when you pick it up but isn’t soaked.
Beetles like to burrow during the day in this moist bedding. The web doesn’t have much information about changing the matting, but the bag recommends switching all of the matting out about once a month.
Preparing the Food
Then put in the branches and the food. To make sure that the jelly doesn’t make the bedding dirty, you can place it in a food plate.
Be sure to change the food every day, preferably in the evening, to make sure this nocturnal beetle has fresh food as he is waking up.
Water for drinking is unnecessary, as the jelly and fruits provide enough, but be sure to keep his/her soil moist — which leads to the next point.
Hydration
Beetles are susceptible to dehydration. In nature, they hide under leaves and in dark places. Therefore, keep their case out of the sunlight!
To keep the bedding hydrated, you can buy a special hydrating bottle (available at 100 yen shops, home and garden centers, etc.) and just stick it in the bedding as shown on the bottle.
If you want to re-moisten the soil and/or aren’t using a humidifier, be sure to dampen various places but not pour water directly on the beetle.
Also, to keep the case hydrated, one website advises putting vinyl over the case and poking holes in the vinyl to let some air in. Leaves in the case also help keep the soil from drying out.
How Many Beetles
Most websites recommend not keeping more than one beetle together, as fights or babies might break out. Also, too much humidity or leaving food for too long will invite unwanted bugs and mites.
Mites
This is quite important, and a lesson learned through experience: Rhinoceros beetles naturally have a small number of mites on them. For this reason, many people keep the beetles outside.
If you keep the beetle inside, make sure to take measures to prevent these mites from multiplying.
One method is a charcoal mixture put into with the matting. Stores sell this and other “dani” (the Japanese term for mites) prevention products near other kabuto mushi products.
Some brave souls go as far as to pick the mites off the beetle gently with a toothpick. Many websites are conflicted on whether or not the mites will hurt the beetle, but they are yucky none-the-less, and some may bite humans.
Last step: enjoy your new friend!
Rhinoceros Beetle Trivial
Do Rhinoceros Beetles Bite?
Rhinoceros beetles don’t sting or bite! Also, they won’t stab you with their horn. Still, they are very strong and their legs are quite prickly.
Do Rhinoceros Beetles Fly?
Rhinoceros beetles CAN fly!
Keeping in mind that they can fly, but that they are pretty much harmless (unless their prickly legs deter you), rhinoceros beetles can be picked up. Since they are shy, though, it’s best not to do this too much, as it will stress them out.
Do Rhinoceros Beetles Make Noise?
These beetles don’t make much noise, except for the sounds of scurrying and an unexpectedly loud buzzing sound when they flap their wings.
What is Rhinoceros Beetle Lifespan?
I didn’t find much on beetle lifespans, but many places indicate a lifespan of less than a year, including the pre-beetle stage.
Rhinoceros Beetle Breeding
Breeding beetles requires a little bit different care and is more involved, so this information is only regarding how to keep a healthy celibate beetle.
Rhinoceros Beetle vs. Hercules Beetle
Rhinoceros beetles are also called Hercules beetles because they are really strong! In Japanese, their name is “kabuto mushi.” “Kabuto” means “helmet,” usually referring to the samurai armor helmet. “Mushi” means “bug.”
Disclosure
Keep in mind that I am not a beetle expert. The information provided here was compiled and translated from the Japanese sources listed below.
Sources:
Kokusan kabuto mushi shiikuhou
Thinking of getting a sawagani (Japanese freshwater crab)? Check out these instructions!
Interested in how to take care of a kuwagata mushi (stag beetle)?
Hi, I have an l3 rhino beetle larvae, and I haven’t changed the substrate in about a month. One day I saw that a few mushrooms popped up, I don’t know if they’re good or bad, do you know?
The mites on the beetle are usually good mites, not the parasitic type. They’re there to keep the bad mites away from the beetle. So yea.
Hey, thanks for the detailed information! 🙂
Since moving to Japan, my 4 year old son has been amazed by bugs. We bought him a beetle cage from the 100 yen shop, and he’s been collecting small beetles throughout the summer, though most of them don’t last very long without the right care. He has been asking to get a kabuto mushi for a while now, and to my surprise, a neighbour brought one over for him today (not sure where she got it from though!) Now I’m trying to find out as much information as I can to help him keep it healthy. She brought some cucumber slices with it, but having read what you said about watermelon, I’m wondering if cucumber is okay? We have some cucumber plants in the garden, and his small beetles devoured the bits I put in.
Also, quick question – can you keep the paper cutter beetles? We’ve seen a few of them around and wondered (though my son is scared to pick them up because of the name).
My pleasure! It was fun looking it up.
That’s lovely of your neighbor.
This website states that watery fruits and veggies such as cucumber, eggplant and watermelon should be avoided. The same website and many others recommend banana.
Paper cutter beetles aka Asian long horned beetle have a reputation of being pretty gentle and it seems some people keep them.
To avoid being bitten, though, you’ll want to hold them by their back.
(They have rather strong jaws for chewing trees. They also will sometimes make a surprising creaking noise if you hold them.)
You may wish to try Google translate on the below sites for tips on caring for paper cutter beetles.
How to care for kamikiri mushi
The correct way to care for kamikiri mushi
Hi! Are there any particularly good websites to buy larvae & adult beetles in the US? I’d rather not have to pay money for an importing permit and have to wait months for everything to be finalized.
Unfortunately, I am not familiar with any websites that sell beetles.
The first stop I would take is your local pet store. They may be able to order one or point you in the right direction to find one.
Aw that’s too bad but thank you anyway! I do know a seller who offers the two species of Rhinoceros Beetles native to the US but they are not as impressive as the Kabutomushi or other exotic species. Also this is probably one of the best articles I have read on taking care of Rhinoceros beetles, good work!
Thanks again!
My pleasure 🙂
Thank you for the kind compliment.
I hope you find a good beetle!
Thank you for your kind words!
I hope you find your perfect pet 🙂
yes bugs in cyberspace is a really good website, I just bought a rhino beetle from there and it got delivered alive (unlike those other companies from asia)
Stigma, from the North-East Coast of the US:
Its amazing the amount of helpful information one can find on the most bizarre subjects, this included. I just started to raise my own beetles from L1 an L3 larvae, at the moment. I’m also an extreme cheapskate and handy person, so I often go out of my way to collect the materials that are free and available around me for rearing the larvae. The only thing I’ve bought, outside of the larvae, has been the compost to make the substrate.
Though you mention a lot of interesting facts about the adult care and info, I was hoping to find more about the larvae. Right now I’ve manage to find excellent rotten wood and I’m using an old aquarium heater to keep the substrate nice and warm this winter to decrease the instar time of the larvae and keep them from entering hibernation mode.
That in mind, do you happen to have any knowledge on how hot or cold is too extreme for healthy larvae/beetles?
Anything you many know helps, but I didn’t hear any info about larvae so I may be one the wrong article for this.
Hi Stigma!
I’m glad you found this article interesting.
Unfortunately, my schedule doesn’t allow for research, translation and a full write-up on kabutomushi larvae and breeding. However, I’m happy to look up your question.
Most sites simply said that for standard Japanese kabuto mushi larvae ‘room temperature’ is fine and not to worry too much about temperature as long as you keep the larvae out of direct sunlight.
This site gave a more concrete range of above 5 degrees C and below 30 degrees C (41 degrees F to 86 degrees F). Still, it says not to worry too much, simply to keep the larvae at room temperature and avoid temperatures below 5 degrees C.
The site mentioned above also has other details about raising larvae, so it may be worth trying to GoogleTranslate it.
I hope that helps!
what do they eat. i fed them apple and they do not seem to eat it. #sad face 🙁
Congrats on your new friend! I’m sorry he’s not eating well. According to Wikipedia, in the wild, rhinoceros beetles often eat sap, nectar and fruit. In captivity in Japan, most people feed them special ‘beetle jelly’ and fruits (non-watery fruits such as bananas are most recommended).
Good luck!
I am raising an EASTERN hercules beetle larva from the USA. My larva is currently L2, but it tried to bite me. Anything to prevent that, or anything about beetle larva aggressiveness?
-G.
Hi there. Surfing the Japanese net, I saw a few Yahoo questions and blog posts about getting bitten by the larvae. However there was nothing conclusive about preventing it. A few of the answers to the Yahoo questions suggested that larvae may bite if they feel threatened and that some larvae (like Atlas Beetles) may just be more aggresive and may bite at just being touched.
Like I said, though, just anonymous commentors on a website and nothing about preventing bites.
Good luck!
Hi! I just got to Japan (Okinawa to be exact) and i wanted to breed and take care of some rhinoceros beetles, and i have this one rhino female beetle in a small cage (looks like the cage they use for catching it and i just found it in our porch) and i want to know if where can I get some beetles that I can start with? I already have some jellies that I can feed them with and a food stand (its a wood with a hole in the middle) and some anti-mites deodorant that looks like tiny rocks, i forgot to buy the bedding and yea. Ill wait for your reply!
PS: I dont know what the “6-three=” is so i just answered it with a random number lol
Hi!
I hope you are enjoying your time in Okinawa. Actually, I bought my beetle at a Toys R Us in Japan. I’ve also seen them sold at home centers like Cainz. I don’t know how prevalent they are in the wild, but in Kanto, you can find them in the woods at night, especially near bright lights.
Good luck with your beetles!
How thick should the soil be for this beetle ?
pls answer it asap , thannk you
According to the Koka-City website (first result searching for this topic in Japanese), the insect mat should be 15 to 20cm thick.
This is extremely helpful. THANK YOU! We, too, are living in Tokyo and just bought 3 kabuto mushi larvae at our local fish store for 300y each. I have 3 little boys and we are so excited to watch them grow. Having an english resource is wonderful. I apologize in advance if we now regard you as the ‘beetle bebe’ expert and enlist your help raising them up. 😉 Arigato gozaimasu! 😉
Doitashimashite 🙂 Good luck raising your kabuto mushi! It sounds like twice the fun raising them from larvae.
How often should you feed the rhino beetle? (with jelly and/or other fruits)
Hi Gary,
According to most of the sources I’ve read, rhino beetles should be fed once per day, preferably around noon. The next day, the old food should be taken out and new food put in, around the same time.
One beetle jelly or piece of fruit per day should be sufficient. Of course, if the beetle seems to be eating more than that, then it’s probably okay to put more food in. Just be sure to change the food daily, in any case.
Hope this helps!
Hi
I need help. I don’t know when to feed them I. I am going to try to feed them every evening.
Hi!
Long answer short, according to the Japanese website Nanapi, beetles should be fed once a day around noon. Since beetles are nocturnal, (human) lunch-time is the best time to put the food in the case, since the beetle will be resting. This will cause the beetle less stress and keep it from flying away.
The food should be exchanged everyday.
The website recommends one beetle jelly per beetle per day. The plastic lid to the jelly should be taken off, but the jelly should be left in the little cup. See the website for pictures.
Some people feed fruits to their kabuto-mushi. Bananas seem to be the most recommended, while watermelons and other watery fruits are discouraged, since they can hurt the beetle’s stomach.
Best of luck to you!
Hi
I just got a rhinoceros beetle and a stag beetle. I found them in the wild. Do I have to change the soil every
Day or can I just put water in the soil?
Thank you for your question.
I myself cannot give an authoritative answer, but I took a look around on some Japanese websites to find a proper reply.
This website says that in a normal season (that is, the lifespan of a rhinoceros beetle, although I don’t know about stag beetles), you should not have to change all of the mat. You should only change soil that is too damp (not just slightly moist) or has a food spill. Every once in a while, you should wipe dirt off of the sides of the case and change just the surface soil. Changing the soil everyday will cause stress for the beetle. The website also states that spraying the soil everyday isn’t necessary. Only put water on the soil if it seems to be getting dry.
In addition, this other website says that you should only change the soil in the case if the soil if food or excretion has made the soil messy. Unhygienic conditions may lead to dani (mites) or nematodes (small worms). So, you should change the soil in the summer when the soil gets dirty, and once right before winter and then once at the beginning of spring.
Long answer short: Changing the soil everyday is not recommended. The soil should be changed only when it is dirty or too damp, and shouldn’t be changed all at once. However, if the soil gets dirty or too damp and isn’t changed, uninvited insects may show up. Also, you should keep the soil slightly moist, but putting water in the soil everyday isn’t needed.
Hello! I am looking for some info about kabuto mushi eggs! We found a female kabuto-mushi outside, and we’ve been taking care of her for about two weeks now. Two days ago she started laying eggs – surprise! I would like to try and raise the babies, but I think we made a big mistake – we mixed both rotten wood mulch and breeding mulch and now our tank for when the babies hatch, but now our tank is very warm – we are worried we killed the babies from the mulch fermenting 🙁 Any advice? Or is warm okey for the eggs? I can’t find any info in English – thank you if you can help!
Hello!
Thank you for your comment.
I’m not an expert on beetle care, so I can’t give an authoritative answer. I looked around on some Japanese websites.
An answer on the oshiete! goo website says that kabuto-mushi won’t lay eggs in a place where the conditions are not suitable for larva. So, if the kabuto-mushi laid eggs, that means that the conditions in the case are right for the eggs to hatch and nine times out of ten, the eggs will indeed hatch. The answer goes on to say that just mulch from the 100 yen store is fine and that pebbles can even be mixed in, so I would guess wood wouldn’t be a problem. I couldn’t find any websites that made mention of temperature, unfortunately.
Again, I am not sure myself on this since I’m not an expert and have never brought up baby kabuto-mushi, so I also found this forum where you might want to post your question. The forum is mainly for reptiles, but it has a very active insect/spider section as well.
Best of luck to you.
Thank you! I appreciate your feedback 🙂 I know you aren’t an “expert” but you sure sound like it! I wish I could read more Japanese.. sigh! Thank you again 🙂
You’re very welcome!
I’ve learned a lot about beetles through researching everyone’s questions on the many useful Japanese sites out there. I wonder if there is an opening somewhere for an apprentice beetle-keeper. 😉
Thanks for this list, it’s very helpful to see something like this in English. If I may add, one of the books I have (in Japanese) also mentions to be careful of mold growing, as it can harm the beetle. Now, I’m not exactly sure how to prevent this, as it seems like a balancing act between keeping things moist for the beetle while NOT making it moldy, but that’s what the book mentioned so I thought it might be helpful to know. Enjoy your beetle!
Hi James,
Thanks so much for the comment and additional advice.
I’ll take a look around and see if I can find any tips on how to keep the soil moist while preventing mold.
Pesky mold!
Thank you for the information. I also have a Kabuto Mushi in PR, USA!
You are very welcome. Good luck with your kabuto mushi!