by Michael Cermak and Jamie Stuart


The Green Tree Python, Morelia viridis, is a tropical rainforest species found on Cape York – Australia, Papua New Guinea and some parts of Indonesia. Green Tree Pythons are nocturnal (active at night) and arboreal (living in trees), with a specially adapted (prehensile) tail for climbing and luring. The juveniles are either yellow or red / orange in colour for the first year or so of their lives, then they turn green, some with yellow, white or blue markings, which makes them perfectly camouflaged in their habitats. Green Tree Pythons are ambush hunters, that is, they sit and wait for a prey to get within their reach then they quickly secure the prey with their long teeth and constricting technique. Like all other pythons, Green Tree Pythons are oviparous (lay eggs), and under normal circumstances, females display maternal care by incubating their eggs inside their coils. Their lifespan is assumed to be around 15 years, males reach sexual maturity at the age of around 2.5 years, whilst females mature at 3.5 years.


Before acquiring a Green Tree Python, it’s essential to have an enclosure of appropriate size and shape, fitted with
a heating system, water container and perches – all well tested. Unlike other snakes, Green Tree Pythons do not
require a hide box. It is paramount to check your State / Territory licensing system to be sure that
you are allowed to keep this species, and also check the licence conditions.
It is also very important to ensure a reliable food supply for your snake(s) and have at least some
food on hand (in a freezer) before your new Green Tree Python arrives.
Perhaps the most important step of all is to READ AS MUCH AS POSSIBLE about keeping this
unique species before you get your snake. We strongly advise to read published literature (books,
magazine articles, scientific papers) rather than asking questions on Internet forums. A list of
references is provided on the last page of this care sheet.

SELECTING YOUR Green Tree Python

It pays to do some research to find out who is breeding Green Tree Pythons, what “types” they breed, and how good is their reputation. You are perfectly entitled to ask questions (and you should), about the snake(s) you’re interested in, their parents, health history and also about the parent’s reproductive history, e.g. how many good eggs the female laid and how many slugs, the body weight of the newborn babies, etc.. It’s a good idea to establish a relationship with the breeder in case you need some after-sale advice or want to buy more snakes from them at later stage.


When buying a Green Tree Python, ask the breeder (and insist on it) to put the snake into a bag rather than leaving it sitting on the perch in a small box during transport. There were some tragic consequences in the past when babies were sent perched on a “MacDonald’s straw”. One could assume that the snake will sit tightly on the perch but it’s not so. Once packed in a freight box, the snake is in the dark, like if it was night and will move around, threshing inside the small box if the parcel is roughly handled. Also, a plastic straw is very slippery and the snake would have to use all its muscle power to hold on, which can put a lot of strain on its spine. The bag with the snake should be held in place in the shipping container with loosely packed shredded newspaper or similar packaging material to avoid any free movement. If air-freighted, snakes should be packed as per Australian Air Express standards, or they may refuse to carry them.



Small snakes don’t require large enclosures and for a hatchling, we recommend 2-4 litre container that is taller than wide, preferably made from a clear, see-through material. The basic furnishings include: at least one, preferably more horizontal perches, placed in the top half of the enclosure, a water dish and some kind of substrate. It’s a personal preference what you use for substrate, it can be paper towel, a layer of sphagnum moss, etc., kept moist at all times. It’s not a good idea to have the substrate too wet, or worse, having standing water instead of substrate. The amount of ventilation you provide depends on the outside temperature but some ventilation is absolutely necessary. In dry areas (most of Australia) it’s essential to spray the inside of the enclosure with water to boost the humidity. Using an atomizer (spray bottle), spray the interior lightly, so the water doesn’t run down the sides, it’s OK to spray the snake as well but it’s not necessary. If you do, the snake may drink from the droplets on its body or the walls but they are perfectly capable of drinking from a water bowl, just like the adults do. It’s best to spray tap-hot water rather than cold because it cools off very quickly as it’s forced through the nozzle. Cold water can get too cold and cause a thermal shock if sprayed onto the snake.

Very young Green Tree Pythons are quite small and their skin is thinner than that of most other species, so high relative humidity is especially important for the first few months of life. If a tiny Green Tree Python has trouble shedding, it can complicate management very quickly because they are quite delicate and can’t be handled as readily as the young of other species. Make sure the substrate is kept moist, whether you use paper towel, sphagnum moss or some other medium. If using paper towel, change it daily if possible to avoid mould problems. In most cases, it is only possible to get a small temperature gradient in a plastic tub, but this is quite adequate for Green Tree Pythons as long as the temperatures range from about 25°C to 29-30°C. In cool climates (most parts of Australia south of the tropics), two lines of heat cord, or a small heat mat placed under the tub is sufficient to keep them warm. In very cold weather, it can help to place a towel or similar insulating material over most of the tub to create a warm, insulated environment, otherwise the tub will lose heat as fast as it absorbs it through the bottom. (Note: NEVER use a heat mat without a thermostat – even the smallest heat mats can overheat and set fire to an enclosure, with serious consequences for the animal… or even your house!


To prevent any digestive problems or the dreaded rectal prolapse, we recommend feeding once a week or every 5-6 days – one food item. Obviously, Green Tree Python hatchlings would not take anything bigger than a pink mouse for several months. You can use defrosted or freshly killed pinkies; sometimes it helps to wash the pinkie in tap-hot water to get rid of the mousy smell. Remember – baby Green Tree Pythons don’t feed on mice in the wild and the mousy smell is not imprinted in their genes to be recognised as food. It’s not necessary to feed Green Tree Pythons after dark when they’re active. If feeding in daylight, first of all you have to wake up the snake by gently probing its coils with the food (held in tongs / long forceps) until the snake flicks its tongue out and starts moving a bit. Like all animals, snakes are individuals with individual responses to food being offered to them. Some Green Tree Python babies will smell the food and strike immediately, others will take it very gently, whilst some have to be provoked into a defensive mode. This technique requires some experience, the keeper needs to know what level of provocation (prodding the snake around its neck with the pinkie) is safe and also needs to know when to stop if the snake doesn’t strike. Sometimes the snakes strikes and bites but doesn’t grab the pinkie – there is a fine line as how long to proceed for without stressing the snake too much. It’s really hard to give a precise recipe here, best to watch someone who can demonstrate this technique. If this fails, you can try scenting the pinkie with chick down, frog, quail or lizard, some breeders have success with starting stubborn feeders on newly hatched quails or quail heads, depending on the size of the snake.

Once the snake takes the food in its mouth, step back and do not disturb until the food is down in the stomach. This only applies in the first or second instance, after one or two meals, the snakes are not so sensitive to disturbance.

If the enclosure is in a cool room, there could be a problem with feeding because as you open the enclosure, cold air will enter and that may affect the snake’s appetite. Baby Green Tree Pythons are very small snakes, and their body mass doesn’t allow them to hold heat for very long. Always make sure the inside / outside temperature is the same or pretty close.

Always keep juvenile Green Tree Pythons in individual enclosures. Their feeding response is not only triggered by the smell of the prey but also by movement – any movement. Feeding two hatchlings in one enclosure could result in one grabbing the other and that can be very messy.


Baby Green Tree Pythons are no different to other snakes when it comes to defecation, except – they like to poo into their drinking water. Personally, I take advantage of this dirty habit and replace the water container with a new one each time. I use small disposable sauce cups seated in another cup that is glued to the bottom of the container. It’s not only easy and hygienic but it also prevents any spills. Some keepers go overboard with hygiene, keeping reptiles, especially new-born juveniles in almost sterile conditions, this can only lead to health complications later in their lives. If the snake was never exposed to bacteria, its immune system will be unable to produce antibodies. Having said that, a sensible cleaning routine is essential.


Baby Green Tree Pythons are much more fragile than other baby pythons. Why is it so? They’re very small, slim and have a very fragile prehensile tail. That means, unwrapping a Green Tree Python from its perch is a delicate operation so it’s best to tickle the snake a little so it gets off the perch itself rather than pulling it off. Green Tree Pythons of any age generally don’t like to be handled, so to keep you snake healthy and happy, keep any handling to a minimum, particularly during the day when these nocturnal creatures sleep.


Australian Green Tree Pythons

Article by Michael Cermak published in Scales & Tails

Download the pdf.


Cairns Symposium

Article by Michael Cermak

Download the pdf.

Green Tree Pythons : CrittaCam : AnimalBytesTV

Join Peter as he travels to Cairns to see one of the coolest Green Tree Python collections in the World! This place has some amazing snakes and the set up is ridiculous.

Australian Green Tree Pythons ; Join Pete as interviews Michael Cermak from the Green Effect, he explains some tricks and tips he has come up with over the years of keeping Green Tree Pythons.





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“Mother knows best” Krauss, P., 2009 Scales & Tails Issue 8, Nov-09.

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