Walk into any reptile expo in Ontario and you’ll find table after table of feeder insects — dubia roaches in sealed deli cups, crickets chirping in stacked boxes, mealworms writhing in plastic tubs, the odd tray of hornworms glowing an unsettling green. It’s a lot to take in when you’re new. It’s also easy to assume that any feeder insect is roughly equivalent to any other, that the main variable is price, and that whatever the pet store sells is fine. None of that is quite right.
The insect you choose — and how you prepare it — has a meaningful impact on your reptile’s long-term health. Get-able nutrition, calcium-to-phosphorus ratios, digestibility, gut content, and the animal’s ability to actually catch and consume the prey all vary significantly by species and life stage. This guide runs through the major feeder insects available in Canada, what they’re good for, where they fall short, and how to make every feeder you offer as nutritious as it can possibly be. It sits alongside our complete reptile diet guide — read that one for species-specific feeding schedules and portion sizes.
We feed hundreds of insects weekly across the animals we keep for Toronto Reptiles experiences — Ember the bearded dragon alone eats 40–60 dubia roaches a week during growth phases. We’ve tested what actually works in practice, not just what looks good on a nutritional chart.
Key Takeaways
- Dubia roaches are the gold standard feeder for most lizards and juvenile snakes — high protein, good calcium-to-phosphorus ratio, can’t climb smooth surfaces or chirp at 3am
- Crickets are widely available and accepted by picky eaters but are more labour-intensive to maintain, louder, and have a worse calcium-to-phosphorus ratio than dubias
- Mealworms are fine as a treat but should never be a staple — they’re high in fat and their chitin shell can contribute to impaction in younger animals
- Gut-loading is non-negotiable — an insect fed poor food passes poor nutrition; what the feeder ate last 24–48 hours is what your reptile actually gets
- Dusting with calcium powder at every feeding, and calcium + D3 2–3 times per week, corrects the calcium-to-phosphorus deficit inherent in almost all feeder insects
Why Feeder Insect Choice Actually Matters
Every insect has a different nutritional profile. The number that matters most in reptile feeding is the calcium-to-phosphorus (Ca:P) ratio. Reptiles need a Ca:P ratio of approximately 2:1 in their diet to absorb calcium effectively. Almost all feeder insects have an inverted ratio — more phosphorus than calcium — which is why dusting is essential, not optional. Some insects are worse than others in this regard (mealworms are particularly bad; dubias are among the best). Without correcting the ratio through dusting and gut-loading, even a reptile eating enthusiastically every feeding day can develop metabolic bone disease over months.
Beyond Ca:P, you’re looking at: protein content (higher in active growth phases), fat content (watch this in adults, especially sedentary ones), moisture (hornworms and silkworms contribute significant hydration), digestibility (chitin shell thickness varies — mealworms have a lot, dubia roaches have little), and feeder size relative to your animal’s bite capacity. A feeder insect that’s larger than the gap between your reptile’s eyes is too big — risk of impaction and stress from struggling prey.
Dubia Roaches — The Workhorse
Dubia roaches (Blaptica dubia) have become the default feeder insect for serious reptile keepers, and the reasons are practical, not fashionable. They have a favourable calcium-to-phosphorus ratio compared to most other feeders. They’re around 36% protein by dry weight. They don’t climb smooth glass or plastic, so escapees stay in the container. They don’t chirp, jump, or smell as strongly as crickets. Their soft exoskeleton makes them easier for animals with incomplete dentition — hatchlings and juveniles — to break down. And they breed readily, so colony maintenance is an option for high-volume feeders.
Drawbacks: they’re slower-moving than crickets, which can be a problem for animals that hunt by motion (some leopard geckos get bored of them). They also have a slower grow-out time, which means if you order the wrong size, you’re stuck with it for longer than you would be with crickets. In Canada, dubia roaches are legal in most provinces but banned in some warmer regions out of invasive-species concern — in Ontario and across most of the country they’re fine to keep.
Crickets — The Accessible Standard
House crickets (Acheta domesticus) are everywhere — every pet store that sells reptiles stocks them, they’re cheap per unit, and many reptiles that reject dubias will eat crickets enthusiastically because of the movement. They’re a perfectly serviceable feeder insect for adult animals when properly gut-loaded and dusted.
The problems with crickets are well-known to anyone who’s kept them: they chirp (very loudly, constantly), they smell (ammonia builds fast in a warm enclosure), they die easily if the container gets too hot or too cold, they can bite or harass a reptile if left in the enclosure overnight, and their calcium-to-phosphorus ratio is worse than dubias. Live crickets should never be left in an enclosure with a reptile that isn’t actively hunting them — a cricket can inflict surprisingly serious wounds on a sleeping or post-shed lizard. Put in only as many as your animal will eat in 10–15 minutes, remove any survivors.
Mealworms — Useful Treats, Poor Staples
Mealworms (larvae of Tenebrio molitor) are the most commonly over-used feeder insect in beginner reptile keeping. They’re easy to store (keep them in the refrigerator and they stay in larval stage for weeks), leopard geckos love them, and they trigger a strong feeding response in most insectivorous species. But they are not a staple, and feeding them as one leads to problems.
Mealworms are high in fat (around 13% by fresh weight compared to dubias at around 7%) and have a thick chitin exoskeleton that is harder to digest, particularly for juveniles. A diet heavy in mealworms over time contributes to obesity in adult geckos and has been linked to impaction, particularly in younger animals. Use them as a treat — once or twice a week alongside a better staple feeder — or as an enticement for a reluctant feeder. Our leopard gecko care guide covers what leopard geckos actually need in their diet and why mealworms alone aren’t the answer.
Superworms — For Adults Only
Superworms (Zophobas morio) are large darkling beetle larvae — significantly bigger than mealworms and appropriate only for adult, large-bodied lizards like adult bearded dragons, blue-tongue skinks, and large chameleons. They’re higher in protein than mealworms but share the fat and chitin concerns at scale. One practical distinction: superworms bite back. They have small mandibles that can pinch the inside of a reptile’s mouth, so always use feeding tongs and never drop them into an enclosure unsupervised. Offer no more than 1–3 per feeding as a supplement, not a replacement for a leaner staple feeder.
Hornworms and Silkworms — The Hydration Feeders
Hornworms (Manduca sexta) and silkworms (Bombyx mori) occupy a different niche from the insects above: they’re low in fat, high in moisture (around 85% water by weight), and highly digestible. In a reptile that’s dehydrated, refusing water, or coming off a respiratory illness, a few hornworms can be remarkably effective at improving hydration status quickly. Silkworms are similarly high-value nutritionally, with a better calcium content than most feeders.
The catch: both require specific plant-based diets to raise (hornworms on tomato-horn diet or pepper-horn diet; silkworms on mulberry leaves or artificial mulberry chow) and have a very short shelf life once they stop being fed. Buy them in smaller quantities more frequently, don’t stockpile them. They’re best used as high-value treats or medical feeders rather than a rotation staple.
Gut-Loading: What You Feed the Feeder Is What You Feed Your Reptile
Gut-loading means feeding your feeder insects highly nutritious food in the 24–48 hours before offering them to your reptile. An insect that has been sitting in a dry container eating cardboard egg carton for three days delivers almost no nutrition. An insect that has been eating collard greens, sweet potato, and a commercial gut-load supplement delivers dramatically more. The difference in calcium content alone between a freshly gut-loaded cricket and a “dry” cricket is several hundred percent.
Good gut-load foods: collard greens, mustard greens, dandelion greens, squash, sweet potato, apple (no seeds), carrots. Commercial gut-load supplements (Repashy Bug Burger, Mazuri Gut Load) are good complements. Avoid oxalic-acid-heavy greens like spinach and beet tops as gut-load — they bind calcium and reduce absorption. Citrus and avocado are toxic to many insects and should be avoided.
For a gut-loading protocol that maps to specific species’ nutritional needs, see the feeding section of your species’ care guide — our bearded dragon care guide covers the specific calcium-heavy greens we use in gut-load for Ember’s roaches.
Calcium Dusting — The Non-Negotiable Step
Even a perfectly gut-loaded feeder insect has an inverted Ca:P ratio. Dusting corrects this. The standard protocol for most insectivorous reptiles:
- Put your feeders in a clean, dry plastic bag or small container
- Add a pinch of calcium carbonate powder (no D3)
- Shake gently until insects are lightly coated
- Offer immediately — the dust falls off within minutes
- 2–3 times per week, substitute a calcium + D3 supplement for the plain calcium
The split between plain calcium and calcium + D3 matters because D3 is fat-soluble and can accumulate to toxic levels if given in excess. Animals with access to proper UVB lighting synthesise their own D3 and need less supplemental D3 — those without UVB (a husbandry problem in itself) rely on it entirely. In practice, most keepers use plain calcium at most feedings and calcium + D3 twice weekly regardless of UVB access, and this protocol has worked well across decades of captive reptile keeping.
Feeder Insect Comparison at a Glance
| Feeder | Protein (approx.) | Fat (approx.) | Ca:P Ratio | Best Use | Notes |
|---|---|---|---|---|---|
| Dubia Roach | 36% | 7% | ~0.5:1 (best of feeders) | Staple for most lizards | Soft exo, quiet, can’t climb |
| Cricket | 21% | 6% | ~0.2:1 | Staple (secondary to dubias) | Loud, escapable, bites |
| Mealworm | 20% | 13% | ~0.1:1 | Treat only | High chitin, impaction risk in juveniles |
| Superworm | 17% | 18% | ~0.1:1 | Adult treat | Bites; adults only |
| Hornworm | 9% | 3% | ~0.5:1 | Hydration/treat | Very high moisture, great for sick animals |
| Silkworm | 9% | 2% | ~1:1 | High-value treat | Best calcium content of any feeder |
Values are approximate and vary with gut-load quality. All feeders benefit from calcium dusting regardless of natural Ca:P ratio.
How Many Feeders Does My Reptile Need?
Feeding volume guidelines vary by species, age, and metabolic rate — consult your species-specific guide for detail. General principles:
- Juveniles (under 6 months): feed daily, as many appropriately-sized feeders as they’ll eat in 10–15 minutes. Growth is the priority
- Sub-adults (6–18 months): every other day, same 10–15 minute window
- Adults: 2–3 times per week for most insectivores; some large-bodied lizards can go to every 3–4 days. Watch body condition, not just schedule
- Feeder size: no larger than the space between the animal’s eyes, measured at the widest point
What do bearded dragons eat at each life stage, with specific insect-to-plant ratios? See our full breakdown of what bearded dragons eat — the ratio flips from 70% insects / 30% greens as juveniles to around 30% insects / 70% greens as adults.
Where to Buy Feeder Insects in Canada
In the GTA and across Ontario, your options are:
- Local reptile specialty stores: typically stock crickets, mealworms, and dubias in multiple sizes; quality varies depending on how recently they were restocked and how they’re being kept in store
- Reptile expos: usually the most variety and freshest feeders; Ontario Reptile Expos in Mississauga and Burlington run several times a year
- Online Canadian breeders: several ship live feeders with heat packs in winter; order Mondays to avoid weekend warehouse delays. Shipping live insects in January to Northern Ontario is a calculated risk
- Breeding your own: dubia roach colonies are straightforward and scale well; a 10-gallon tub, heat mat, egg cartons, and a food dish is all you need to start a colony that can sustain a single bearded dragon indefinitely within 6 months
One important point for Ontario keepers: live feeder insects cannot be legally imported across provincial or national borders without a permit. Buy Canadian, from Canadian sources.
Frequently Asked Questions
Can I feed my reptile insects from my backyard or garden?
No — or at least not safely. Wild-caught insects can carry parasites, pesticide residue, herbicide residue, and heavy metals absorbed from soil. Fireflies and lightning bugs are toxic to reptiles (some fatally so). Wild-caught earthworms from treated lawns can carry pesticide loads sufficient to sicken a small lizard. Stick to commercially raised feeders where you know the food source. If you want to add variety, houseflies from a commercially raised culture are one of the few wild-caught insects that can be used relatively safely — but even then, raised cultures are better.
My reptile won’t eat dubias. What do I do?
Some animals, particularly individuals raised on crickets from hatchling, resist switching because dubias move differently — slower and more predictable. Try warming the dubias slightly before offering (a warm insect is more active). Try tong-feeding: hold the dubia by a hind leg and wiggle it in front of your reptile rather than placing it in a bowl. Feeding in a separate container with just the reptile and 5–6 dubias with nowhere to hide can also help. Most resistant animals convert within 3–4 weeks of patient effort.
How do I store feeder insects without them dying?
Each feeder type has different needs: dubias like warmth (28–32°C is optimal for breeding; 24°C is fine for storage short-term), egg cartons to hide in, and a small dish of gel water and food. Crickets do better cooler (18–22°C), well-ventilated, with egg cartons and light food. Mealworms should go in the fridge (8–10°C), which suspends their development indefinitely; take out what you need, let them warm up before feeding. Hornworms and silkworms are the trickiest — keep them at room temperature on their food source and use them within 1–2 weeks of receiving them.
Can I use freeze-dried insects instead of live ones?
As an emergency or occasional supplement, yes. As a staple, no. Freeze-dried insects lose significant nutritional value in processing, can’t be gut-loaded (you’re feeding the nutritional content of whatever the insect ate at the time of processing, which may have been poor), and don’t trigger the hunting response that live feeders do. Some animals become habituated to freeze-dried feeders and then resist live prey. Use live insects as the primary protein source whenever possible.
What’s the difference between calcium powder and calcium + D3 powder?
Plain calcium powder is typically calcium carbonate — it provides the mineral directly and has no effect on D3 levels. Calcium + D3 supplements include a pre-formed vitamin D3 that aids calcium absorption. Animals with proper UVB access synthesise D3 naturally through skin exposure to UV-B radiation, so they don’t need much supplemental D3. Animals without UVB (which ideally should be a temporary situation, not a permanent husbandry approach) depend more heavily on dietary D3. Most protocols use plain calcium 4–5 days per week and calcium + D3 2–3 days per week as a safe baseline regardless of UVB access.
How do I gut-load crickets if they keep escaping?
The standard gut-load container for crickets is a plastic tub with a secure lid — the cheap 10L storage boxes from any dollar store work perfectly. Crickets can’t climb smooth plastic. Add egg carton pieces for hiding, a small bowl of gut-load food (no standing water — they drown in water dishes; use water gel crystals or fresh vegetables for hydration), and keep the container in a warm area. For 24–48 hours of pre-feeding gut-loading, this is all you need. If you’re buying crickets in bulk and keeping them longer, invest in a dedicated cricket keeper with tubes that allow you to load and unload without the escape risk.
Are waxworms a good feeder insect?
Waxworms are the reptile equivalent of deep-fried candy — extremely high in fat (around 25%), low in protein, and essentially nutritionally empty by feeder insect standards. Reptiles love them because fat tastes good. Use them rarely: as an enticement for an animal that hasn’t eaten in weeks, as a conditioning food for a female coming off egg-laying, or as the occasional high-value reward. A leopard gecko fed primarily waxworms will become obese and develop liver disease. One or two per week alongside a proper staple is fine; five waxworms per day is not.
Getting insect nutrition right is one of the highest-leverage things you can do for a captive insectivorous reptile’s long-term health — and it’s genuinely straightforward once you understand the principles. If you’d like to see what well-fed, thriving reptiles look like up close and ask our handlers questions about diet and husbandry in person, book a Toronto Reptiles experience for your next event or join one of our terrarium workshops in the GTA.