10. Humidity and Spraying/Misiting
Green tree pythons are indigenous to New Guinea and its surrounding island chains. This equatorial nation is home to lush tropical rain forests that receive high annual rainfalls and experience high average temperatures. Therefore, in their natural environment chondros are typically exposed to relative humidity ranging from 80-100%. Reproducing a natural environment in captivity is not always as simple as it seems. Several variables interact in the wild to create the dynamic conditions chondros live in. These include temperature, rainfall, relative humidity, barometric pressure, elevation, wind speed, cloud cover, and forest density, among others.
Since green tree pythons naturally live in humid environments, the most logical approach is to reproduce similar conditions in captivity. Keepers use different methods for boosting humidity, ranging from elaborate automatic misting systems to simple hand sprayers. Until they are "dialed in" to the enclosure, misting systems require a more comprehensive understanding of the variables that influence humidity (cage size, ventilation, etc.) and are less attractive for beginners. Although more labor intensive, hand sprayers are inexpensive, simple to use, and ensure a more interactive approach. While foggers are used in captive husbandry of amphibians, they are not viewed as effective for GTP enclosures.
Regardless of the equipment used, it is important to remember that a constantly moist environment will become a breeding ground for bacteria and fungi (yeast and mold). Therefore, it is necessary to create a "damp/dry" cycle in which the enclosure is given ample time to dry before misting or spraying again. There is no clear cut formula for achieving this schedule, and it will ultimately be determined by variables including:
- Cage size
- Degree of saturation of the cage's walls and substrate
- Type of substrate being used
- Air temperature within the cage
- Ambient room temperature
- Geographic location and external weather conditions
Trial and error is the best way to determine how often to mist/spray, how much water to use, and how long it will take for the enclosure to dry out. Some keepers employ a 24-hour cycle in which a cage is sprayed once every 24 hours. The amount of mist/spray is limited to a volume that ensures the cage will completely dry out in approximately 12-16 hours after spraying. However, some keepers wait an additional day or two after drying before misting/spraying again. And some keepers will only mist every third day. It must be emphasized that there are no set rules regarding humidity and the two most important factors to consider are proper hydration and preventing an environment that promotes the growth of bacteria and/or fungi.
Spraying not only raises humidity, but may also promote movement/activity. This in turn may increase the chance that a water bowl is discovered and used. For this reason many keepers spray toward the end of the day, just prior to lights out. Spraying after lights out is discouraged since it can trigger a feeding response and may lead to injury if a perch or cage door is struck.
Chondros are often directly sprayed since many will drink water from their coils. Watching them drink from their bodies is a unique and interesting sight. On the other hand, some keepers feel concerned that direct spraying will induce stress. Ultimately it will be necessary to learn to "read" your chondro to determine if that is in fact the case. Regardless, chondros often bury their heads when being misted, and in isolation, this is not an indication of stress.
Neonates up to about 6 months of age are more sensitive, and drying time between sprayings should be reduced. With more frequent spraying they are likely to drink more readily and defecate more often. This will require more frequent cage clean-outs but will provide confidence that adequate hydration is being achieved.
While spraying is a common way to boost humidity, some keepers choose to simply dump water onto the substrate itself. How effective this is can be measured by the degree of condensation that results on the doors/walls. The effectiveness of this method will depend on the type of substrate used and the amount of water dumped. But it is quite effective when using paper towel and newspaper.
Another way to raise humidity, especially during winter months when air is dryer, is to use a whole room humidifier. They are fairly cheap and can be helpful if you plan to be away from your collection for a few days. In that case it would also be advised to give the snake a fresh bowl of water and wet the substrate before you leave. A 2-3 day drying time will not harm your snake and will likely reduce the mold and bacteria count.
It should be noted that for many years it has been accepted that high humidity is a necessary component of captive GTP husbandry. While this continues to be the most popular approach, some experienced enthusiasts successfully house chondros in much drier conditions. Keepers using this method likely mist or wet the substrate during a shed cycle, especially during drier winter months. As long as the snake is well hydrated, drinking regularly, and sheds cleanly (in one piece), the low humidity method can be used successfully. However, this method is not recommended for beginners. Until you have a concrete understanding of your cage dynamics and your animal, the damp and dry out method is recommended.
One of the most important variables to ensure the health of chondros in captivity is hydration, and this is especially true when a drier environment is kept. Regardless of the method chosen, poor hydration will quickly lead to poor health and must be avoided.