by Clay Davenport
Grandis day geckos are found in northern Madagascar, where they enjoy a wide distribution, including several islets off the coast. They are aboreal, spending practically their entire lives in trees, where they feed primarily on insects. They also fed on nectar and pollen.
These geckos make excellent candidates for set up in a naturalistic vivarium. House them in a vertically oriented enclosure, using sturdy plants, such as snake plant and pothos, for perching and basking sites. These plants can be planted directly in the substrate, or left in the pots. Heat should be provided via a basking light. The temperature closest to the heat source should be 85-88F during the day. The temp can be allowed to drop to 70-75F at night. Use a thermometer to verify the temperature and adjust the wattage of the bulb to reach the proper temp.
Mist the enclosure daily to maintain a relative humidity of 50-90%. Mist during the morning so the cage is allowed to dry over the course of the day. A constantly wet environment can lead to skin infections.
I am not an advocate of the requirement of full spectrum lighting to sucessfully maintain these geckos. I have hatched and raised many of these and other species without any full spectrum lighting at all. In larger cages I do use a flourecent fixture to fully light the cage, because being diurnal, photoperiod is an important aspect of their husbandry.
Day geckos accept a variety of invertebrate prey. The staple should be crickets. Wax worms, mealworms, butterworms, and young grasshoppers can be used as supplemental foods to provide variety, as occasionally they will become bored if only one type of prey is offered for long periods.
Another important part of their diet is fruit. Fresh slices of fruit should be offered twice weekly to adults. Another alternative is peach, apricot, or banana baby food. Hatchlings should have access to fruit daily.
You should supplement the diet of adults 2-3 times per week with a quality calcium supplement. Hatchlings and juviniles should be supplemented daily. Choose a calcium product that contains vitamin D3 and no phosphorus. It should also be low in vitamin A.
Day geckos breed readily in captivity. House them in pairs year round. Make sure the female is at least one year old and has adequate stores of calcium in her body, evidenced by the "chalk sacs" that form on either side of her neck.
Some breeders cycle their geckos by cooling the temps slightly, and reducing the photoperiod. I have not found this to be required to sucessfully reproduce this species.
You can often determine if a female is gravid by observing the underside of her belly, to check for the presence of developing eggs. When you suspect you have a gravid female, you should provide a suitable egg laying site in the cage. This can be a length of bamboo 2 inches in diameter placed vertically in the cage. The cardboard centers of paper towel rolls work well for this purpose also. After the eggs are laid, remove them and incubate at 82F, with 75-80% relative humidity. They will hatch in 50-65 days.