A giant stag beetle is an awesome beetle to keep as a pet due to its cool pincers and large body size. If you are reading this, you are probably considering keeping it as a pet. This guide shows you all you need to know about giant stag beetle care, and how to breed them!

Keep the giant stag beetle grubs in moist flake soil until they turn adults. Place the adult beetles in ventilated containers, and feed them with beetle jelly. Mist the container regularly. Relocate the gravid female to a container with moist flake soil and decaying logs. Remove the female after she resurfaced from the flake soil.

Continue reading to learn more.

Introduction to Giant Stag Beetles

Lucanus elaphus, also known as the giant stag beetle, can be found in the southeastern United States. The male beetles have a pair of enormous pincers. They fight each other using their pincers for the right to mate. A male giant stag beetle can grow up to 2” in length. Female beetles are smaller in size and have much smaller pincers.

Giant stag beetle. Photo by Andy Reago & Chrissy McClarren / CC BY 2.0

Getting a Giant Stag Beetles

The giant stag beetles are not a common beetle species. If you are lucky, you can buy them from your local pet store or online store. Always ask for a care sheet 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. However, as the grubs spend all their time underground, feeding, you will need to be patient if you are starting from grubs. Bear in mind that not all grubs can survive to adults, so you should buy 2 or more grubs.

Always check the age or larval stage of the beetle before buying. Giant stag beetle can live up to 9 months. You won’t want to buy a 8 months old adult beetle. If you are getting the beetle from local store, look for sign of injury or lost limbs.

If you are adventurous, you can try to catch some adult giant stag beetles by yourself during the summer. Obviously you need to be at where they are found: Alabama, Arkansas, Delaware, District of Columbia, Florida, Georgia, Illinois, Indiana, Iowa, Kansas, Kentucky, Louisiana, Maryland, Michigan, Minnesota, Mississippi, Missouri, Nebraska, North Carolina, Ohio, Oklahoma, Ontario, Pennsylvania, South Carolina, Tennessee, Texas, Virginia, and West Virginia.

To catch them, prepare a black light and a white sheet. Go to a wooded area far from urban light pollution. Find an open space and shine your black light onto the white sheet around midnight. This will attract any insects to fly towards the light. If you are lucky, you can get your beetles. 

Giant Stag Beetle Care: Grubs

Caring for giant stag beetle grub is very easy. Simply keep the grub in flake soil or kinshi. Change the substrate once every 4 months depending on container size. Stop changing substrate once the grub builds a pupation chamber.

You might be familiar with flake soil, which is the substrates used for many beetle grubs. The flake soil serves as the food for your grub, and here is a recipe for flake soil that you can use.

On the other hand, kinshi is another popular substrates used by Asian stag beetle hobbyist. You can use kinshi instead of flake soil if you want to grow bigger stag beetles.

Fill up a 1 pt (~500 mL) container with flake soil as substrates. Make sure you keep the substrate moist at all times but do not add too much water to the extent that the soil becomes soaking wet as it may kill the grub. House 1 grub per container. 

The container should be well-ventilated and kept away from direct sunlight. Mist the substrate when it gets dry. Ideally you should keep the temperature between 68-75 °F (20-24 °C).

Change the substrates every 4 months until the grub turns into pupa. When you change the substrate for the first time, transfer the grub into a bigger container: 2 qt (~2L) container for male and 1 qt (~1 L) container for female grub.

But how do you know which grub is male and which is female? To sex the grubs, look at the dorsal part of their abdomen. You can see a visible white or yellow color spot through the abdomen. This spot is said to be the ovary of the beetle when it turns into an adult. Another method is by comparing the size of their head capsules. Male has a larger head capsule than a female grub.

Why do we change the substrate by specific interval instead of checking the amount of feces? Well, it is quite difficult to ascertain the feeding rate of your grubs because the grubs often smear their feces. The smeared feces release bacteria, which help the grubs to digest some substrates before the grubs feed on them. 

When changing the substrates, always retain 10% of the substrates and place the grub onto the old substrates. This helps to retain some of the beneficial bacteria.

Female beetles generally grow faster than male beetles, and may get too old to breed when the male beetles emerge. If you plan to breed giant stag beetles, you can keep the female grub at 68°F (20 °C) to delay its growth and keep the male grub at 75 °F (24 °C) to accelerate its growth rate. 

The first molt occurs after 6 weeks, and it takes another 8 weeks for the second molt. After that, the grub will spend another 9-18 months before it finally molts into a pupa. Prior to each molt, the grubs generally stop feeding.

When it is time to pupate, the grub will move to the bottom of the container to build a pupation chamber, within which it pupates. Do not disturb the grubs once it starts building the pupation chamber. It takes about 6-8 weeks for the adult beetles to emerge from pupae.

If you accidentally break the pupation chamber while changing substrates, you can still save your beetle following this guide.

Dormant Period

After emerging, the adult giant stag beetle will remain dormant for up to 6 months! You can leave them in the same container where they emerge or transfer them into the housing for adults. They do not need food during this period.

Do not disturb your beetles during this period. It is crucial to let the beetles complete their dormant period naturally. Otherwise, there will be adverse effects on their fertility, overall fitness, as well as egg hatchability.

Read more on how to take care of your beetle during dormant period here.

Giant Stag Beetle Care: Adult Beetles


Giant stag beetle. Photo by Andy Reago & Chrissy McClarren / CC BY 2.0

The dimension of your housing for a beetle should be at least 3 times the length of your beetle in length, 2 times in width and 2 times in height. For each additional beetle, increase another 50% to the length and width of the housing.

Bigger housing is better as it gives more space for the beetles to move around. An adult male giant stag beetle can be housed comfortably in a 1 gal (4 L) tank. Do not keep more than 1 male in the same housing as they may fight.

You can use peat/soil mixture in 1:1 ratio as the substrates for the housing. Alternatively, you can use non-soil bedding such as hay or coir. The giant stag beetles, especially the female beetles, like to hide in the substrate. Hence, make sure the depth of the substrates is at least 2 times the thickness of your beetle.

Giant stag beetles are good fliers. Make sure the housing is covered and ventilated. You should also put some tree branches or tree bark for the beetles to climb. Keep the environment moist through misting using a bottle sprayer from time to time.

How to Feed Adult Giant Stag Beetles

A male Lucanus beetle with huge mandibles. Photo by Patrick Coin / CC BY-NC 2.0.

Feed the giant stag beetle with cut fruits such as a slice of banana, orange, apples, or pineapple a quarter of their body size. Place the fruit onto a sauce plate so that you can clean it easily. Remove any unconsumed food everyday 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 rot 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 follow to prepare the beetle jelly.

The giant stag beetles do not eat much. You should adjust the volume of food you give them through trial and error to avoid wasting your food, especially if you are feeding them beetle jelly.

The adult giant stag beetles typically live for about 9 months. 

Breeding Giant Stag Beetles

You can let your beetles mate after they have exited the dormant period. Note that mating will reduce the lifespan of the beetles. Do not let your beetles mate if you do not intend to breed them. 

It is best to let your beetles mate when they are still young. Older beetles have lower fertility and will produce less viable eggs.

After mating, transfer the gravid (pregnant) female to a nursery container. Put 1-2 big rotten woods (can be purchased from beetle stores) into the nursery chamber and fill the chamber with flake soil around 8” (~20 cm) in depth. ⅔ of the rotten wood should be buried in the flake soil. Cover the chamber with a lid and make it ventilated

The rotten wood should be soaked in water overnight and air-dried before use. Tree barks should also be removed so that the beetles can easily chew through the wood for oviposition.

Keep the flake soil moist but not wet. The adequately moist substrates should hold together in a shape when squeezed with both hands, but there should not be dripping water. Excessive moisture will kill the eggs! Keep the container well-ventilated and covered. Place the chamber away from direct sunlight.

Continue to provide the gravid female with jelly. The female will lay around 50 small eggs at the bottom of the substrates. Due to the small size of the eggs, I would advise you to leave them in the nursery container and let them hatch. 

The mother should be removed from the nursery chamber one month after she was placed into the chamber. This is to prevent her from eating her own grubs, which she would mistaken them as grubs of other beetles. Do not dig out the female beetle if she is inside the substrates to avoid disturbing the grubs or destroying the eggs. Instead, wait for it to appear on the surface for feeding to remove it.

One month after you removed the female beetle, you can search for the grubs in the rotten wood and flake soil, and move them into a separate container. By that time they have grown bigger and can be easily searched.

Here’s my recommended supplies that you can consider getting for your giant stag 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.

Handling the Beetles

The giant stag beetles are not aggressive. You should be able to hold them easily. Always grab their thorax instead of their legs because their legs are very fragile. Both male and female beetles may pinch you when given a chance, but it is not extremely painful.

Be careful not to drop the grubs when handling them because they may die of falling. Never forcefully pull the beetles from a surface they grasp because that may break their legs.

Things That Can 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 giant stag 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. 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.

Remember to check out our recommended books to learn more about keeping giant stag beetle.