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What size insects should you feed your reptile at each age?

Reptiles · Food ·

Published by Planète Pets · managing editor: Clément Lacaille · how our guides are written

The basic rule: never feed an insect wider than the gap between your reptile's eyes. A juvenile needs smaller, more frequent prey than an adult, or it risks digestive blockages or internal bites from an oversized or poorly digested prey item.

Leopard gecko resting on a piece of driftwood
Contents · 5 sections
  1. How do you judge the right insect size?
  2. How often should you feed by age?
  3. What happens if a reptile is fed oversized prey?
  4. How do you scale up prey size gradually?
  5. Frequently asked questions

How do you judge the right insect size?

Visually measure the width of your reptile's head between the eyes: that is the limit for the width of the cricket, worm or locust on offer. A 15 cm juvenile bearded dragon should only get small crickets a few millimetres across, never adult-sized ones.

How often should you feed by age?

  • Juvenile (0-6 months): small prey, once or twice a day;
  • Subadult (6-18 months): medium prey, every other day;
  • Adult: larger prey, three to four times a week depending on the species.

Careful gut-loading of feeder insects stays essential at every age to guarantee proper nutrition.

What happens if a reptile is fed oversized prey?

Prey that is too large can cause regurgitation, an intestinal blockage or, more rarely, an internal injury in young animals. Bites from a large cricket or worm poorly digested inside the stomach are also a real risk in stressed animals that do not finish their prey right away.

How do you scale up prey size gradually?

Increase insect size in steps, watching your reptile's appetite and digestion rather than following a rigid schedule: two animals of the same species and age can have slightly different needs. If in doubt, a pair of feeding tongs also helps control the size offered and avoid accidental bites.

Frequently asked questions

Should uneaten prey be removed?

Yes, always within 15 to 30 minutes: live insects left to their own devices can stress or bite a reptile that does not feed right away.

Does a reptile refusing to eat always mean the prey size is wrong?

Not always: shedding, stress or temperature can also explain a refusal. If it persists for several weeks, consult a vet who specialises in exotic pets.

Can you mix several insect sizes in the same meal?

It is not recommended for a juvenile: a uniform, appropriately sized offering makes it easier to monitor exactly what gets eaten.

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This guide is part of Planète Pets’s Reptiles universe. Our advice is general in nature: for any health concern, your veterinarian remains the only reference.

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