Hercules beetle, Dynastes hercules is one of the largest insects in the world. They are the dream pets for beetle lovers. In this guide I will teach you how to keep and care for Hercules beetles.
Place the adult Hercules beetle in a 4 gallon tank filled with coir. Add tree bark for the beetle to climb. Feed the beetle with beetle jelly and mist regularly. Keep gravid beetles in a separate container for egg layings. Put the emerged grubs in flake soil. They turn into adults in 1-3 years.
Keeping Hercules beetles is easy and requires low cost. There are a few important things that you need to note in order to get your beetles healthier and live longer. Do bear in mind that you may need a permit to keep Hercules beetle, depending on where you live. Continue reading to learn more.
Hercules beetle is a rhinoceros beetle known scientifically as Dynastes hercules. It is found in the Central and South America. This species is notable for its exceptionally long horn on male beetle. The length of a Hercules beetle including its horn can reach up to 7″!
A female Hercules beetle can lay 40-100 eggs. The eggs hatch into grubs in around 30 days . It takes about 2 months for 1st molt and another 2 months for second molt. After the 2nd molt, the grubs continue to feed for another 1-1.5 year before it turns into pupa. The pupa then emerge into adult in 1 month. The adult Hercules beetles can live for up to 6 months.
While the adult beetle looks sluggish and slow, they can fly. The first pair of wings on the beetle is called the elytra. The elytra are the hardened wings used to protect the hindwings, and the hind wings are used for flight.
Getting a Hercules Beetle
Depending on where you are, uou can buy Hercules beetles from your local pet store or online store. Make sure you ask for recommendations from the seller on how to take care of the beetles.
You may want to buy the grubs as they are way cheaper than an adult beetle. Depending on size and breed, an adult beetle can cost you up to $500. However, as the grubs spend all their time underground, feeding, you will need to be patient if you are starting from grubs. You should buy at least 3-4 grubs because not all grubs can successfully turn into adult.
Always check the age or larval stage of the beetle before buying. Hercules beetle can live up to 6 months. You won’t want to buy a 7 months old adult beetle. If you are getting the beetle from local store, look for sign of injury or lost limbs.
There are a lot of beetle enthusiasts out there and as a result of that, there are various notable breeds for you to choose. Some breeds focus on the overall size, some on the length of the horn, and some on the thickness of the horn. A grub of a noble breed can be more expensive than the adult of a normal breed.
You do not have to buy a noble breed because a normal breed is equally enjoyable. But if you do want to buy a noble breed such as the famous HirokA breed, make sure you buy from a reliable seller to avoid scam.
Preparing Housing for Adult Beetles
A male Hercules beetle has a very long horn on his thorax and another one on his head while the female doesn’t. The large horns may look dangerous, but they actually cause no harm to us. Due to the large horns, a male Hercules beetle requires a bigger space. If you put the male in a small tank, they may break their horns when they try to move in the tank.
If the adult beetle is not more than 5″ (~13 cm), a 4 gal (~16 L) tank is sufficient. If your beetle is more than 6″ (~15 cm), you need to at least use a 16 gal (~60 L) tank. A 5 gal tank typically sufficient to house at 4 females together. Do not put 2 males or more in the same tank because they will fight!
Fill the housing with coir up till 3-4″ (7.5-10 cm) in depth. You should also put some tree barks or smooth branches for the beetle to climb onto. When the beetle turns upside-down, it needs to hold on to a solid surface to turn around. Otherwise, it will die trying. Cover the tank with a lid.
Place the housing away from direct sunlight, somewhere cool. Exposure to direct sunlight for a long period will kill them. Keep the environment moist by misting with a garden sprayer and make sure the tank is well ventilated. Temperature at 68-77 °F (20-25 °C) is suitable for the beetles.
How to Feed Adult Hercules Beetles
The adult Hercules beetles naturally feed on rotten and/or overripe fruits. You can give them a slice of banana, orange, apples, or pineapple half their body size. Place the fruit onto a sauce plate so that you can clean it easily. Remove any unconsumed fruits every day to prevent growth of molds.
You should consider feeding your beetles with beetle jelly. It is more convenient to use in terms of preparation and storage. Moreover, the jelly doesn’t grow mold as easily unlike the fruits. Some beetle jellies even boast various fitness benefits such as improved longevity, stronger beetles, and larger offspring. Here is a recipe for beetle jelly that you can try by yourself if you can’t find them in stores.
The beetles should obtain enough water from their food. You don’t need to prepare them additional water.
How to Breed Hercules Beetles
If you want to observe the mating process, separate the male and female beetles into different container as soon as you bought/caught the beetles or as soon as you are able to sex the grubs. The adult male and female beetles naturally mate when they see each other. To have a more successful mating, wait until the adult beetles are at least 1 month old so that they are fully matured for this holy task.
During mating, the male beetle will mount itself onto the female to attempt copulation. Sometimes the female will resist and run around. If this happens, the female is not ready. Separate them and try again after a week or 2. It may take up to 1 hour for the mating to complete. Wait until the male withdraws his genital from the female, which signifies the end of mating. You should see a thin thread on the tip of the female’s abdomen after mating.
After mating, I would again separate the male and female. This is because the male may want to mate again in the subsequent days, but the mated female can be reluctant, which causes stress in the female.
Note that mating (and repeated mating) will reduce the lifespan of both male and female beetles. If you do not plan to breed them, do not mate them.
You will need to place the gravid (pregnant) female into a separate chamber.
Prepare a nursery chamber using a 16 gal (~60 L) container. Fill the container with flake soil (recipe here) up till 8″ (20 cm) in depth. Add some water to make the substrates moist. The adequately moist substrates should hold together in a shape when squeezed with both hands but there should not be dripping water.
Cover the chamber with lid to prevent the beetles from escaping, and ensure there is adequate ventilation in the chamber. Place the chamber away from direct sunlight
Continue to feed the gravid female beetle in this chamber with beetle jelly or fruits. She may choose not to eat though. The female beetle will start laying eggs a few weeks after mating. The white colored eggs resemble seeds and are about 0.2″ (0.5 cm) in length. They hatch in 30 days.
How to Care for Hercules Beetle Grubs
Caring for Hercules beetle grubs is very straightforward. Keep the grub in a ventilated container filled with moist flake soil. Change the spent flake soil every few months. Transfer the grub into a bigger container as it grows. It takes 1-3 years for the grub to turn into adult.
After the eggs hatch, handpick the grubs and place them each into a 8 oz (250 mL) container fully filled with flake soil. The depth of flake soil should be at least 5 times the thickness of the grub. The grubs naturally feed on rotting woods. Do not press the substrates too hard because you need it to be ventilated.
Make sure you keep the substrates moist at all times but do not add too much water to the extent that the substrates becomes soaking wet as it may kill the grubs. Make sure the container is ventilated and placed in the dark.
By separating the grubs into different containers, if anything goes wrong (eg. 1 of the containers gets too dry or wet), the whole brood will not be wiped out. There is one caveat though. When kept in separate container, the male and female tend not to emerge into adult around the same time. As a result of that, the female may get too old to when the male is ready to mate.
A workaround for this is to prepare a separate tank where you put in multiple grubs of both sexes. The female grubs seem to release a certain pheromone that encourage the male to pupate around the same time. It doesn’t work every time though.
Another method is to regulated the growth rate by temperature. You can keep the female grub at 68 °F (20 °C) to slow down the growth rate, and keep the male at 77 °F (25 °C) to accelerate the growth rate.
But how would you know which grub is male and which is female? Male Hercules beetle grub has a small marking/dent on the center of the third-to-the-last ventral abdominal segment. This marking/dent is only visible in the 3rd instar, and it is more conspicuous as it approaches the late 3rd instar stage.
As the grubs continue feeding, they produce a lot of droppings. When the amount of dropping becomes more than the substrates, remove 70% of the soil-dropping mixture and replenish with new substrates. If you want, you can use a sieve with bigger holes (or wire mesh) to filter out the dropping so that you have more reusable substrates.
The size of the beetle’s horn is dependent on the quality and quantity of food consumed by the grubs. Hence, you want to make sure they have more than enough food.
The purpose of keeping some old substrate is to reduce the shock on the grubs when a new substrate is added because the new substrate may have different bacteria composition and pH vs the old substrate.
When you notice your grub has molted, move it together with the substrate around it to a 16 oz (500 mL) container, and top up the container with more new substrates. Move the grubs into a bigger container (1 gal/5 L) after the second molt. A smaller container may work, but will result in a smaller beetle.
At a certain stage the grub will start building a pupation chamber using its dropping. Eventually, the grubs will molt into pupae in the pupation chamber and emerge into adults in 1-3 months after pupation. A newly emerged adult has soft skin and it takes up to a few days for the skin to fully harden.
If you accidentally break the pupation chamber while changing substrates, you can still save your beetle following this guide.
Color of Adult Hercules Beetles
When the adult beetle emerges from the pupa, you may notice both of the elytra are in dark or black color instead of brownish yellow. You don’t have to worry much about that. The color of elytra is affected by moisture, and the elytra look black when the environment is too humid. You can move the beetle to his housing which should be dryer than the housing for grub. As the environment turns dry, the elytra will slowly turn brownish yellow.
Handling Hercules Beetles
The grubs and pupae are quite fragile. You can put them onto your hand if you want but be careful not to drop them. They will be severely injured and may die if you drop them! Try not to disturb them too much, especially when the late 3rd instar grub is building its pupation chamber. If you break the pupation chamber, the grub will need to rebuild it.
While the adult beetles are protected with a thick layer of armor, you should still be gentle when handling them. The Hercules beetles are not aggressive. You should be able to hold them easily. Always grab their thorax instead of their legs. Their legs are fragile and have spines that might hurt you. Never forcefully pull the beetles from a surface they grasp because that may break their legs.
Be very gentle when dealing with male Hercules beetle because it can get agitated easily. It seems to be annoyed by strong air movement. When you need to open the lid to put in the female for mating, do it gently. Otherwise the male beetle may be agitated and will attack the female beetle.
Here’s my recommendation on things that you can get for your Hercules beetle. Note that I get a small commission when you buy the items through the links in this page. This helps me to maintain the site without incurring additional costs to you.
Things that May Kill Your Beetles
To improve the survivability of your beetles, pay attention to the following:
Substrate – make sure the substrate you use is pesticide-free and fertilizer-free. If possible, bake your substrate to kill any pathogen before using it.
Moisture – moisture is very crucial for the Hercules beetles at all stages especially the grubs and pupae. They will not survive without adequate moisture. At the same time, too much moisture will hinder their breathing and promote growth of mold, which can kill them.
Mites – Certain mites in the soil can feed on the eggs while some parasitize the grubs of Hercules beetles. These mites are very tiny. If you bake your substrate before using it, it’s unlikely you will encounter them.
If you do encounter them, dispose of all the substrates and replace with a new one. Clean all the containers with soap before reusing them. Try to separate the eggs/grubs into different containers with new substrates.
Mydas fly – The maggots of mydas fly prey for the grubs of Hercules beetles. Again, it is very unlikely that you will ever encounter them, especially if you bake your substrates before using them. The maggot is quite big in size, with length of up to 2″ (5 cm).
Beetle keeping can be a lonely path because it might not be popular in where you stay. I hope this guide encourage more people to join the beetle keeping family! If you are already keeping beetles and want to make your beetle larger, you can refer to this guide!
Remember to check out our recommended books to learn more about keeping Hercules beetle.