Forster's Stag Beetle

Forster's Stag Beetle key facts

Care level

Intermediate

Lifespan

Adult 6mo-1yr

Size

40-100mm

Temperature

20〜27℃

Diet

Tree sap, beetle jelly

Larval Care

Raise in fermented mat or fungal bottle

Notes

Sharp bifurcated mandibles are dangerous; handle with care

Temperature & Humidity

Keep at 20-27°C. It is easiest when held in the same stable temperature band as the related Hexarthrius species.

Housing

Set up a small to medium case with a breeding log and fermented substrate. Add bark or wood as footing so adults can right themselves.

Diet & Feeding

Feed adults beetle jelly. Raising larvae in kinshi bottles or fermented substrate lets you aim for large adults.

Breeding & Egg-laying

Laying in a breeding log is the norm. Bury the log in substrate and split it only after the larvae have grown.

About Forster's Stag Beetle

Forster's Stag Beetle, native to Indonesia's Maluku Islands, features forked mandibles and a glossy body. Intermediate difficulty, 6-month to 1-year adult lifespan, 40-100mm in length.

7 things to know before welcoming a Forster's Stag Beetle

1. 1Temperature control matters

   This species is sensitive to high heat and sudden temperature swings, so keep the enclosure out of direct sunlight in a cool, well-ventilated spot. Pay extra attention in summer to prevent room temperatures from climbing too high, and aim for a stable environment overall.

2. 2Handle the mandibles with care

   The large forked mandibles have a strong pinch and can injure a finger if caught. When picking the beetle up, hold it firmly by the thorax and keep your fingers away from the mandibles.

3. 3Set up the enclosure

   Prepare a case lined with fermented insect mat and a piece of climbing wood, and manage humidity so it doesn't become excessive. Both overly dry and overly damp mat can harm the beetle's condition, so check and adjust regularly.

4. 4Wait quietly before first feeding

   After emerging, the beetle goes through a period before it starts eating, and during this time it's best left undisturbed in a quiet environment. Let it rest in the mat without rushing it.

5. 5Adult lifespan is limited

   As an adult, this beetle typically lives around 6 months to 1 year, which isn't especially long compared to some other insects. Enjoy the day-to-day changes and make the most of the time you have together.

6. 6Insect jelly is the staple food

   The main food for adults is commercially available insect jelly, which is easiest to offer set in a small feeding dish. Leftover or dried-out jelly can dirty the enclosure, so replace it regularly.

7. 7Keep them singly as a rule

   Putting two males in the same case can lead to fierce fighting with their mandibles, so each beetle should generally be kept on its own. Even when pairing a male and female, it's safer to supervise them and keep time together brief.

Frequently asked questions about Forster's Stag Beetle

Q.Can beginners keep this species?

A.This species is considered intermediate difficulty and requires some attention to temperature and humidity management. Prior experience keeping other forked stag beetles makes it easier to handle.

Q.How large does it grow?

A.Adults reach roughly 40 to 100mm in length, with noticeable variation between individuals. The degree of mandible development also affects how imposing each beetle looks.

Q.How long do adults live?

A.Adults typically live around 6 months to 1 year. The exact span can vary somewhat depending on care conditions.

Q.How does it differ from the red-backed stag beetle?

A.It's a closely related species with very similar care requirements. They differ in native range and body coloration, but the same basic care approach applies to both.

Q.Are there any legal restrictions?

A.Forster's Stag Beetle is not subject to CITES.

Useful tools for Forster's Stag Beetle care

Learn more about Forster's Stag Beetle in the encyclopedia

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