According to data from Antananarivo, Madagascar, leaf-tailed geckos have evolved alongside an annual sunrise-sunrise cycle of approximately 13 hours/day during summer and 11 hours/day during winter. The exact numbers aren’t as important as the fact that there is a significant seasonal flux in the amount of daylight vs night. Simulating these rhythms in captivity allows for normal hormonal cycling in reptiles, which in turn improves their circadian rhythms, seasonal cycling, as well as general activity, appetite, and overall health.
The easiest way to accomplish this is with a digital programmable timer — I prefer to use a smart power strip such as this one by Kasa for convenience. Plus, it allows me to automatically sync the lamps to my local sunrise/sunset times.
Although leaf-tailed geckos are classified as crepuscular, they tend to sleep out in the open during the day in the wild, naturally exposing themselves to small amounts of sunlight. Breeders and collectors generally agree that UVB is strongly recommended for the health of Uroplatus geckos.
Since leaf-tailed geckos are crepuscular forest-dwellers, they are classified under Ferguson Zone 1, which means that they don’t need to get a lot of UVB for it to be effective. If you have a Solarmeter 6.5 (recommended), the UVI at the basking branch should be between 1.0-2.0.
The type of UVB bulb you will need to use generally depends on the distance between the basking perch and the lamp, which generally varies with the height of the enclosure you are using. If you don’t have a Solarmeter, here’s a fair baseline for distancing with each bulb type:
The UVB that you choose should span 50-100% of the enclosure’s length.
These estimations assume that the UVB lamp is placed above the terrarium mesh rather than inside the enclosure, assuming a ~30% mesh block. The above estimates also assume that an Arcadia ProT5 or Vivarium Electronics fixture is in use. For more details on adjusting basking distance based on mesh obstruction, see the Facebook group Reptile Lighting > Guides > Guide 1: Using T5-HO lamps above a Mesh Screen.
Note: Bark mimics like the Fimbriatus, Lineatus, and Alluaudi groups are likely to naturally receive more UVB than leaf mimics (Ebenaui group) due to their choice of microhabitat. These are the latest observations by herpetologist Mark D. Schertz.
Given that leaf-tailed geckos are primarily active around nighttime, their eyes are highly sensitive to light — it doesn’t take much to stimulate their day-night cycle, so if the UVB lamp is the only source of illumination in your enclosure, you’ll be okay. However, if you plan to use shade-tolerant live plants as part of your setup (which is extremely helpful for stabilizing higher humidity levels and a necessity of bioactive setups), then you will need a ~6500K LED plant grow light as well to nourish the plants.
By brand, I prefer the Arcadia JungleDawn LED Bar or the Bio Dude Glow & Grow lamp. LED grow lamps should span the full length of the gecko’s enclosure for maximum benefit.
