Feeding Insectivorous Pet Lizards

This may seem like an oversimplified guide to some of the more advanced keepers but the simple questions of what, how much and how often are some of the most common questions we get asked in store by new keepers. We will therefore structure this blog post in a sort of Q&A style format to try and cover some of the most commonly encountered questions.

1.     What size insects should I feed my new lizard?

The general rule of “no wider than the lizards head” is a good starting point, but it sometimes leads people to panic over the size of insect and feed prey items that are on the smaller side of what they should be. Using this general rule of no bigger than the width of the head is appropriate in most cases, but we would allow an extra 25-50% leniency size wise on top of this without any cause for concern. Lizards do have teeth and wouldn’t refuse food in the wild just because it may take a bit more chewing to subdue and swallow.

2.     How often Should I feed insects?

This varies by species and most importantly by age. Many popular species of lizard that fall into the small-medium size category (Up to the size of a bearded dragon or most chameleons). These species will often grow rapidly for the first year to 18 months attaining their maximum adult size by this age. Therefore, during the first 6 months of life we suggest daily feeding, the next 6 months it should be 4-5 days per week, the next 6 months 3-4 days per week and over 18 months old, 2-3 times a week would be sufficient for most species.

3.     What time of day should I feed?

For diurnal species its best to feed them in the morning, an hour or two after lights come on. For nocturnal or crepuscular species feeding an hour or so before lights go out. That said, many species that we think of as being crepuscular are very adaptable in their feeding regimes so if you fed a leopard gecko at lunchtime everyday within a few months it would have learned this routine and would be awake and actively hunting in the afternoon. One final point to mention, no you don’t need to feed multiple times of day, breakfast lunch and dinner are not required, one feed per day is sufficient.

4.     How many insects should I feed?

For fast growing Agamids (E.g Bearded/Rankins dragons), small monitor lizards (E.g. Ackie / Mulga) or most chameleons (E.g Panther/Yemen), they are going to consume a minimum of about 10-15 insects per day, but the reality is that if you feed them more, they normally just grow faster, so as long as there are no more than 5-10 insects left in their enclosure at the end of the day you can feed them as many as they will eat throughout the course of a day.

For most of the commonly kept geckos, we would suggest around 6-8 insects per day as an appropriate number, again they may eat a few more, they may eat a few less, try to ensure there are somewhere between 6-10 insects in the enclosure at a time to ensure they have ample opportunity to hunt throughout the evening/night but without being overwhelmed.

If you put too few insects in the enclosure you may think your animal isn’t eating, this could simply be that it hasn’t been successful in hunting them as there were too few to give it a sporting chance.

For omnivorous species you may be replacing some of their insect feeds with other foodstuffs but remember the younger the lizard the more frequently it will need insects in its diet to fuel its rapid growth.

5.     What type of insects are best to feed?

Variety is always beneficial, just remember that “worms” such as mealworms, morio worms, wax worms etc are all the larval stage of an insect so contain much higher levels of fat and as such for most species they should only be fed as a treat. Crickets and locusts are the two most commonly used staple foods with dubia cockroaches also gaining in popularity. In terms of fat content, cockroaches are slightly higher but can still be used regularly as part of a varied diet.

Different feeder insects will be favoured by different species either due to size, taste, or activity pattern. Often larger species will prefer larger prey, hence why locusts and Dubia cockroaches tend to be the staple for Bearded dragons and larger chameleons. The difference in activity pattern is also important to note, crickets will often remain active at night so often make a preferred food source for nocturnal and crepuscular geckos, while locusts will climb during the day so are often favoured by arboreal species.

6.     Do I need to feed the insects?

Absolutely, this is one of the most often overlooked elements that separates an average reptile keeper from a good reptile keeper. Whatever you feed to your insects ends up in your lizard, this process is often referred to as “gut loading”, or making sure that the insects’ gut is full of good nutrients at the time it is consumed. Not to mention the added benefit of making your live food last longer. Locusts can be a little tricky to gut load as they do best when fed on dark leafy greens such as cabbage or kale, but they will often take specialist insect foods in moderation. Crickets and cockroaches can be gut loaded on a wide variety of table scraps such as vegetable peelings, carrots, apple etc and both will readily accept commercial gut loading foods. Some of our favourite insect foods that we use in store are Arcadia Insect Fuel and Repashy Superload. Both are excellent choices.

7.     Is it safe to leave insects in the enclosure?

Yes. The internet is awash with horror stories of people saying their lizard got bitten by the feeder insects, but the bit they don’t tell you is that in those cases I guarantee that one of the following is true. Either the lizard was already ill and therefore lethargic. They put far too many insects in the enclosure or of a grossly inappropriate size. Or simply, that they hadn’t bothered to feed their insects, so they put a bunch of starving insects into an environment where the only thing for them to eat was by attempting to nibble on the very predator they had been put in an enclosure to feed. If you use an appropriate number of insects of a sensible size and well gut loaded there is no risk to a healthy lizard. If you are concerned at leaving insects in overnight, simply place a dish with some of the insect’s food on it into the lizards enclosure so that the insects have something to eat while they are in there.

8.     What about calcium and multivitamin supplements?

It is crucial to always dust your insects before every feed with a high-quality calcium supplement like Arcadia Ca, or our favourite is Arcadia Earth Pro A. The easiest way to dust your insects is to tip a few into an empty container or Ziplock bag and add about ¼ of a teaspoon of calcium powder then shake until coated. Do this just before you feed the insects to your Lizard as over the course of several hours the insects will clean the calcium powder back off themselves. You can also leave a small dish of calcium powder in the enclosure with your lizard to allow them to “self-supplement” their calcium intake but if you want to do this you should still dust the insects as well, a dish of calcium is not a substitute for dusting.

9.     How do I know what supplement to use?

This is almost a separate article so we can only skip over it briefly, the main thing to be aware of is that some supplements contain added vitamin D3 or vitamin A (among other preformed vitamins), e.g Revitalise D3, while some don’t contain preformed vitamins but do contain natural precursor chemicals and mineral clays E.g Arcadia Earth Pro A. If you are using good quality UVB lighting you shouldn’t need to use additional dietary Vitamin D3 for most species. All of our starter kits contain the supplement we would recommend for specific species based upon the lighting selection we have paired with it in the kit. Some species have more specific supplement requirements such as for chameleons as can be seen by the multiple supplements in our chameleon starter kits. Some amphibians particularly dart frogs also have a requirement for elevated levels of Vitamin A in their diet, we recommend Repashy Vitamin A+ for this. For specific supplement related questions please pop in and have a chat with staff. Also remember that supplements with added vitamins will degrade over time so you should always replace unused supplements after 6 months from opening.

10. Can I culture my own insects or feed them from my garden?

Culturing insects can be fun and rewarding but is also a time-consuming process for very minimal returns with most of the commonly used live food species of insect. We can talk you through how to do it, but I guarantee after a couple of months you’ll decide it’s not worth the hassle. Despite having to purchase tens of thousands of insects every week to feed our own animals we don’t culture our own insects as its just not an effective use of our time, we buy ours as its just easier that way.

Regarding using wild insects, technically this can be done, and if done in a responsible way this is an excellent way to add variety to your lizard’s diet. However, there are some important things to remember, wild collected insects can harbour parasites and be carrying high levels of pesticides or pollutants so its important to gather them from an area you know they will be free from these environmental contaminants. Finally, you must be certain of what insects you are using as food, not only are some insects potentially toxic, but the UK is also home to a wide number of protected and critically endangered insects which you must not collect or tamper with. Should you decide to collect wild insects, make sure you get a good insect identification guide and only do this at your own risk.

11.  How should I store my feeder insects?

It depends upon the species, but all feeder insects will survive better if they are transferred to a larger holding pen or enclosure than the small tubs they arrive in. We like to use the large Exo Terra Faunarium or Exo Terra Cricket pen for this. Most feeder “worms”, such as wax worms, mealworms etc will do best if stored in a cool environment at around 15C, for crickets, locusts, cockroaches etc they all prefer to be kept warm but not hot, ideally 25C or more. You can always store the insects in a cupboard underneath your enclosure or even on top of it to add a bit of warmth to your insects. Wherever you store your insects make sure that they have good airflow, if you try and store them in a sealed Tupperware with limited ventilation they will perish rapidly.