Introduction
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.
Breeding
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.
Summary
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.
