In the wild, crested geckos are a frugivorous (fruit eating) species that will also take insect prey, especially when young. In their native environment of New Caledonia, they have a wide variety of fruits, nectar and pollen available year-round. This means they are not an obligate insectivore, and with two good powdered diets available, you do not need to offer insects for them to attain proper nutrition. Dusted insects can be offered on occasion as a treat and to provide stimulation for those crested geckos that relish “the hunt”!
Because crested geckos are so easy to feed, their diet is often misunderstood. Before the commercial powdered diets were available, captive crested geckos (and Rhacodactylus species in general) were fed babyfood mixed with reptile supplements and crickets. This worked for more experienced reptile hobbyists who understood the need to supplement the diets of lizards and other geckos to prevent nutritional deficiencies that lead to serious disorders such as Metabolic Bone Disease (MBD). However, as crested geckos became more popular and received “starter reptile” pet status, this diet started becoming less and less supplemented. Soon many new keepers became breeders who passed on the notion that all crested geckos needed was babyfood and crickets, with an occasional dusting of calcium. This has lead to numerous cases of MBD and other nutritional imbalances which can permanently cripple and even kill a crested gecko.
The good news is that there are good meal replacement powders on the market that, when mixed with water, prevent MBD and other nutritional issues. Please check out the crested gecko Prepared Diets page for more information on powdered diet options.
For the more adventurous and experienced hobbyist, homemade diets are possible, but are much more time consuming and possibly risky to your pet’s health. It is important to note that insects need to make up a larger portion of the diet when you are feeding a homeade diet.
I’m of the opinion that eating the “wrong” things (any unbalanced diet) is worse for crested geckos than not eating in the short term. Reptiles have a different metabolism than mammals – they are ectothermic (specifically poikiliothermic) or “cold blooded”. Their blood isn’t really cold, but their energy from food doesn’t have to be spent maintaining their body temperature as in mammals. Mammals also have complex brains that use energy. So a reptile like a crested gecko doesn’t need to eat as much in comparison to endotherms or “warm blooded” animals.
However, diet is very important for reptiles as they have a need for calcium and D3 (plus other vitamins and minerals!). In captivity, if we aren’t careful to give them a good balance of these macrominerals and micronutrients, we run the risk of harming them. They can develop Metabolic Bone Disease (MBD) which is a preventable disease with proper diet!
Once a crestie is eating CGD on its own, I think it’s fine to give treats once in a while – no more than 10% of their total diet.