8. Keeping & Breeding Inland Carpet Pythons
...... by Doc Rock

Inland carpets can be found around water courses in early spring, especially if there are north facing rocky outcrops or cliffs nearby. The pictures above show various habitats where the author has found inland carpets in areas like the Flinders Ranges, the Warby Ranges and along the River Murray.


When it comes to a delightful temperament and a robust constitution combined with ease of keeping and breeding, the inland carpet python (Morelia spilota metcalfei), is without doubt at the top of the carpet python list for me. These pythons were first classified as a separate taxon by Wells and Wellington in the mid-1980's and then as a distinct subspecies by the Barkers in their "Pythons of the World: Australia" in 1994. Their main distribution is through southern South Australia, northern Victoria, central New South Wales and south-eastern Queensland where they are strongly associated with the Murray River, its tributaries and drainage systems. Because of this, many herps refer to them as Murray-Darling Carpets, or simply MD’s.

My addiction to breeding Australian pythons can be blamed on the Inland Carpet Python. I had spent years trying to find them in the wild with only minor success. One day I was hunting around a pile of huge boulders on the flood plains of the River Murray in Victoria where I had reliable intel that MD’s could be found. After finding some old shed skins and scat, I came across a number of empty tins of lighter fluid near some of the large fissures where one could expect to find pythons hiding. My guide explained that the pungent fumes created by lighter fluid were used to flush out pythons from deep hiding so that they could be caught and sold on the market for extraordinary profits. That was it for me. I decided I would learn how to breed these pythons, produce them in large numbers and destroy the illegal trade. After enormous effort, a large purpose built breeding facility and great cost I managed to start producing large numbers of Murray-Darlings for the pet trade. Today they are the most common carpet in captivity in South Australia and probably the third or forth most frequently kept carpet in Australia.

In the Wild
Over the years, my wife Diane and I have found inland carpets in many areas across eastern Australia, including the River Murray from NSW down to southern SA, the Warby Ranges, the Adelaide Hills and surrounding plains, through the Flinders and Gammon Ranges and up to Goyder's Lagoon on the Diamantina flood plains below Birdsville, where they show a great deal of variation in colour, pattern and size. While the colours of the inland carpet are not bright and startling like some other carpets, they have a subtle beauty and intricate patterns on their backs, sides and bellies. We have found in most of Murray River region of Victoria that the MD’s (where they are also called Vic Carpets) are generally covered with a dark, almost black pattern contrasted with a lovely silver background. As you move further north into New South Wales the dark pattern becomes a lighter brown colour, and as you move into South Australia increasing touches of maroon appear in the sides of the snakes the further south you go.

Inland carpets inhabit some very harsh environments where they not only can experience long periods of drought and famine, but large changes in temperature from the forties in summer to freezing in winter. It is probably because of this that they are such resilient and robust snakes in captivity.

In Captivity
Amongst the carpet pythons, their quiet temperament is second to none. I have found a number in the wild and in each case I was able to pick them up gently without them attempting to bite. Try doing that with any other sort of mammalian or avarian predator! Why they are so placid is a mystery to me. However, I have noticed that as a general rule of thumb that the further you go north the more irascible carpets tend to become and the further south the calmer. On Nuyts Archipelago a pygmy carpet python lives on the tiny island of St Francis in the Great Southern Ocean off the coast of Ceduna and they are unbelievably placid – but that’s a story for another article.

In captivity, inland carpets feed readily of rodents, or chickens, or just about anything else you might offer them. As babies, they are amongst my favourites because most will start feeding with little effort. They are very tolerant of their cage conditions and seem to be able to thrive in most circumstances. For this reason, they are ideal snakes for the less experienced herp and the ease with which they can be bred under the right conditions makes them an excellent taxon for learning how to breed snakes.

The generic articles I have written for Reptiles Australia on keeping and breeding pythons cover the approach I recommend for M. s. metcalfei, so I won’t repeat it all again here. In particular, I would refer the reader to Reptiles Australia Vol 1:5 on housing pythons and Reptiles Australia Vol 2:5 on breeding preparation, light and temperature regimes. However, I will add a few more pointers that are specific to the most readily available of the inlands, the Murray-Darlings or Vic carpets, and with which we have had the most experience.

Although the Murray-Darling form can withstand relatively high temperatures for a carpet python (I have seen them survive prolonged temps in the high 30’s oC), I have found we get the best results by keeping them cooler than our jungle, coastal or north-western carpets. During the summer, we provide an ambient temperature of 27-30 oC during the day and low to mid twenties at night. During winter, we drop this from a daytime mid twenties to 14-17 oC at night. We provide a basking site throughout the four seasons, but one which is only operating during the early part of the day. Throughout summer, the basking light is on for 2-4 hours starting half an hour after the lights switch on at 6 am. In winter, the basking light is only on for 1-1.5 hours starting at 8:30 am. We aim to provide a basking temperature of approximately 32 to 35 oC. We have found that the best breeding results are achieved by providing strong seasonal temperature variation which is hardly surprising when you consider the environment to which the snakes are adapted.

One of the best times to find MD’s in the wild is around water courses in early spring, especially if there are north facing rocky outcrops or cliffs nearby. I have discovered that they can be found basking and mating during the first warm sunny days of September in Southern Australia. Consequently, we breed ours by waiting until the first sunny days of September where we live near Adelaide and put them together in the evening. So far, this has never failed to create a very strong mating response and a successful breeding outcome. I imagine that in wild populations, the initiation of the breeding season would gradually start a bit earlier the further you move north.

Male inland carpets will fight viciously during the mating season. As gentle as they are towards humans, so they are towards each other in the opposite extreme. Under no circumstances put two of these animals together unattended during the mating season, unless you are sure of their sexes and know from past experience they will be OK together. We have learnt this from bitter experience. The damage these snakes can inflict on each other in a couple of minutes has to be seen to be believed.

When conditions are right and a ripe pair of breeding MD’s are put together they will mate for up to 14 hours. If you find that your snakes hook up for only a few hours and then separate, chances are you have not had a successful mating. Once mating has occurred, we separate our carpets for at least three to four days before introducing them again. If you present the female to the male too often, then the male will lose interest. In the wild, a ripe female is probably mated by a number of successive males before she is ready to risk years of body fat accumulation on producing a clutch of eggs.

Inland carpets will breed at 2.5 years of age. We prefer to give our females an extra year and breed them at 3.5 years. They will breed every year without problems providing you feed the females adequately from when they lay their eggs until the cooling down period in May/June. I don’t like putting the pressure of an annual breeding regime on my female MD’s (although I’m probably just being a softie) and so we breed ours only two in any three years. We keep our males lean as we have found fat males are lazy and don’t respond with the same excitement to a ripe female. (Having lost 14 kilo over the last year, I too can confirm the advantages of weight loss). As described in Reptiles Australia Vol 2:6, we prefer to have more males than females for improved breeding. Although we have an equal number of male and female inland carpets, by resting the females every third year we effectively end up with a third more active males than females each breeding season.

Egg Laying and Incubation
Inland carpets are by no means the largest of the carpet pythons. They are typically quite a bit smaller than the coastal and diamond pythons but larger than the north-western and jungle carpets. Despite this, they lay quite large clutches of large eggs relative to others carpet taxons. We never like to push our snakes too hard so that out largest and oldest females (13 years old and 2.2 metres) only produce 28-30 eggs a season. However, I have seen clutches that have closer to 50 than 40 eggs. This represents a huge commitment of body mass by the females which is probably a consequence of the boom and bust ecosystems they have evolved in. Because of the clutch size, you need to make sure that their nest box is large enough to allow the female to lay her eggs and wrap around them without being restricted by the top or the sides. We use specially made wooden boxes because we have found, unlike many pythons, they are happier with wood rather than plastic.

We incubate our eggs using the standard technique of a 50:50 vermiculite:water mix and incubation at around 31 oC. The eggs should take approximately 55 to 60 days to hatch. We prefer to “tune” our incubator for an incubation period of 58 days to get the best health and feeding result for our neonate MD’s. We do not separate the eggs, but instead leave them in the clump formed by the mother because we find the eggs work better as a unit rather than individually. Inland carpet eggs are about as bullet proof as you can get in the python world. Too wet/too dry/too warm/too cold and they will still generally hatch if originally healthy. I’ve seen a clutch of MD eggs that were laid in a plastic bin by a captured female, the female removed and with no supplementary heating or moisture half the clutch hatched in the bin!

Our hatchlings are kept separately in small plastic tubs with heat tape at one end set at 31 oC in a room with an ambient temperature of around 25 – 28 oC. About 10 days after hatching they shed the little water proof skins that protected them in the egg. We don’t try feeding them until about three weeks later because we have found this gives a stronger feeding response and so less problems later on. They are generally strong mammal feeders as babies and so getting them started on rodents is easy.

If you want a carpet python that has a gentle nature and can become “dog tame”, that is easy to keep and is tolerant across a wide variety of conditions, that will breed readily and whose babies are easy to establish in captivity, then my advice is look no further. I know the trend in herpetoculture is for all the unusual morphs and candy coloured snakes but, if you haven’t already, stop and have a close look at the inland carpets when you get a chance. You will find a diversity in appearance which is reflective of their variable habitats and a subtlety of pattern and colour which is worthy of recognition by the most discerning of herp hobbyists.

Gammon Ranges Carpet Pythons - these are now thought to be more closely related to the south-western carpets (M. spilota imbricata) than the inland capets found in the eastern half of Australia (M. spilota metcalfei).
Inland carpets from along the River Murray (known as Murray-Darling Carpets or MD's for short) and the Warby Ranges (bottom).
Murray-Darling carpets mating.
MD Carpet laying eggs and then incubating them in her hide box.
SA inland carpets hatching - at around 31 oC the eggs should take approximately 55 to 60 days to hatch.
Hatchling inland carpet in hunting pose - they are generally strong mammal feeders as babies and so getting them started on rodents is easy.