Mealworm FAQ

Some Frequently Asked Questions about Keeping Mealworms

What is a mealworm and why would anyone keep them?

This is a mealworm;

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Mealworms are baby mealworm beetles (Tenebrio molitor). They are the larval form of the beetle - meaning they will, if left alone, morph into their mature beetle form. They are not true 'worms' as they have six limbs at the front of the body; which is dark yellow-orange in colour.



Mealworms are not generally kept as pets themselves (though obviously this is possible!) and are most commonly kept for feeding to other animals. There are many reasons for this, as mealworms are:

• Cheap to purchase
• Easy and inexpensive to keep
• Easy to breed
• Easy to feed, i.e. They are slow-moving (unlike crickets or locusts)
• Full of fat and protein (especially beneficial for growing animals)

What pets can eat mealworms?

Most small carnivorous or omnivorous animals can eat mealworms. Mealworms are suitable for:

• Birds
• Rodents/other small mammals - hamsters, rats, mice, gerbils, chipmunks, sugar gliders, bats
• Lizards - geckos, skinks, bearded dragons, chameleons, water dragons
• Fish
• Turtles/tortoises
• Amphibians - frogs, toads, axolotls, newts, salamanders

Can mealworms be purchased in different sizes? 

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Yes - the above sizes are available for purchase.


What pets can eat...?

• Mini mealworms - fish, dwarf hamsters, mice, baby lizards & amphibians
• Small/Medium mealworms - birds, Syrian hamsters, rats, chipmunks, sugar gliders, gerbils, bats, geckos, skinks, amphibians
• Large mealworms - chameleons, bearded dragons, water dragons, turtles, tortoises, large amphibians

Do mealworms need to be fed?

Yes they do. It's known as 'gut loading' and ensure that the live food is healthy when it's eaten. Foods high in moisture are best for mealworms as they also provide their source of water and these include; fruit (bananas and apples) and vegetables (lettuce, potatoes and carrots). Extra food can be added for variety, such as cereals or bread, but should not be the main food given. All fresh food should be removed after 24 hours if uneaten.


What are mealworms kept in?

Mealworms should be kept in a decent sized flat container - something like a lunch box or mini terrarium. It should be at least 2 to 3 inches deep and have smooth sides to prevent escape. A ventilated lid can be added but this is not necessary.

Mealworms enjoy burrowing so a substrate is necessary to keep them occupied. Mealworms are nocturnal in the wild and so this also provides somewhere for them to hide during the day. Materials suitable for bedding include; sand, crushed cereal (e.g. wheat bran, oatmeal), poultry feed mix or other granular feed.


Why are there bits of dried up mealworms appearing (picture)?

The above picture shows what appears to be dried up mealworms but don't panic - it's just the skins! Mealworms shed their exoskeleton (outer layer) whenever they have outgrown it and the result is dry, crispy flakes which at a glance look like dead worms. These pieces of shed skin should be removed as otherwise the container will become full of them.


Why have some mealworms turned white (picture)?

The mealworms shown above are significantly lighter in colour than regular mealworms (see below):

It looks strange but it's completely normal. The white colouration is a result of the fore-mentioned shedding and is what the worms look like when they pop out of their old skin. They are also much softer to the touch.


Why do some mealworms look like this (picture)?

These mealworms are in their 'pupa' state. Although they appear motionless and perhaps dead, they are just going through a metamorphosis (similar to caterpillars). The following picture shows three different stages of pupation:

A fully grown larvae turns into a pupa (left mealworm), slowly becomes more rigid (centre mealworm) and then changes to a dark brown colour (right mealworm). Up to 2 weeks after pupation first began, an adult mealworm beetle emerges. A life cycle is shown here:

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