CAPTIVE MAINTENANCE
This python is hardy in captivity and will tolerate a wide range of environmental conditions. Housing consists of banks of white melamine wood cages in a heated insulated room. Cages have glass-fronted doors and are quite small, measuring 60 cm long, 40 cm wide and 30 cm high.
Substrate consists of 3 mm white aquarium gravel to a depth of 3 cm. Each bank of cages consists of 9 cages, 3 long by 3 high, individually heated by one 40 watt white light globe connected to a room thermostat. Thermostats are connected in tandem in two separate cages and connected to all light globes in the bank of cages. This ensures that cages do not overheat if a globe burns out in the cage containing the thermostat. Temperatures vary throughout the year on a seasonal basis. Cage temperatures range from an absolute minimum air temperature of 17 degrees C in winter to a maximum air temperature of 36 deg. C in summer. Ambient room air temperatures for a five year period are summarised in Table 5.
Daytime heating hours are varied according to the season, from a low of 8 to 9 hours in winter to a high of 14 hours in summer. No heating is used at night, with cage temperatures falling to ambient room temperatures overnight. The gravel in the cage acts as a thermal sink, gaining heat during the day and slowly radiating heat at night. Skylights in the room provide a natural photoperiod for northern Victoria.
Temperatures are cycled throughout the year to initiate breeding responses in the pythons. During spring and summer the temperatures are held within a relatively narrow range of highs and lows. When the breeding season begins in autumn the daytime high and night time low temperatures are changed gradually, with the lowest temperatures recorded in winter in June and July. Daytime high temperatures are increased to compensate for lower night time temperatures and decreased daylight hours.
Cage furnishings consist of the gravel substrate, the water bowl and a hiding spot in the form of a piece of curved Eucalypt bark to offer security. Water is changed weekly using a fresh disinfected bowl.
BEHAVIOUR
Specimens are housed singly for most of the year, by housing them individually it is easier to feed and service the cages. Separation for feeding is not required and social interaction resulting in the formation of social hierarchy and resulting stress is eliminated. They are only paired for mating in the winter, the male is always introduced to the female’s cage. Pythons tend to be solitary by nature, except during the breeding season when aggregations of some species are known to occur.
This species is known for it’s docile nature and is a well-known animal in the pet trade. If bites occur it is generally in the expectation of food being offered to the snake or the smell of food on hands or utensils. Some specimens can become food-conscious to the point of biting repeatedly on handling.
FOOD
The species is generally sedentary in habit, being an ambush predator as well as an active hunter. Specimens can be observed waiting for passing food from the hide box. This posture may be held for hours at a time on successive days and nights. When hungry, specimens will often become very active around the cage searching for food.
Food consists of adult fresh, or frozen and thawed out dead mice on demand. No live food is offered to adults due to the possibility of injury from mice biting the snakes during constriction. Dead prey is often taken and constricted as if it was live, being eaten later. Some specimens will eat prey directly from the floor of the cage without constricting it, whilst others require prey items to be jiggled in front of them as if it were live. It is then taken, constricted and “killed” before being eaten. Older specimens of fifteen-plus years can become geriatric and have trouble feeding on their own, being unable to co-ordinate the strike response. These individuals will often learn to open their mouths for the introduction of a mouse, which they will then swallow with difficulty.
No specific feeding regime is used. Females generally refuse food from April until after egg laying in spring. Males will resume feeding after the mating season during winter. After specimens resume feeding they are fed ad lib throughout summer and autumn. Females need to replace reserves lost in egg production and are fed as much as they will eat. This results in rapid weight gains. Males are fed on a maintenance diet with the frequency of feeding also increasing over the summer months. About two or three adult mice are fed in one meal whenever the snake will eat. At the end of summer females are in what could be described as fat condition and have replenished fat reserves used in egg production. Females are not spelled in successive years of breeding and are bred on an annual basis.
Mutton Bird Oil has been used as a food supplement at a rate of one or two drops on every second or third feed.
BREEDING
Sexing
Sex of specimens is determined by probing the inside of the tail for the presence or absence of hemipenes (Laszlo, 1973).
Mating
Specimens are introduced during May, June, July and August. Most mating activity has subsided by the end of August. The male is always introduced to the female’s cage and will respond by scenting and searching the cage. Courtship and mating usually occurs within one to two days after introduction. The male may chase the female around the cage and mating within several hours may occur and last for several hours. Male combat has been used to induce mating but is not considered essential. An otherwise disinterested male may be stimulated to mate the female following the introduction and removal of another male. The males should be closely observed if introduced as intense fighting can occur and one or both males may be injured. Males will often enter a pre-mating season slough in May and June, and again following the breeding season in September. Females may also enter a pre-mating season slough but not as reliably as males. Matings have been noted to last for several hours and up to twelve hours, and are often observed around dark and in the early morning at the coldest time of day.
Males are generally removed from the female cage after one week, given a week on their own and then introduced to the female for another week. This pattern is repeated in May, June, July and August, with males being rotated through up to six female cages. Males are permanently removed at the end of July and early August.
Gestation
After the mating season females will often become reclusive and hide from view. During late July and August females can be observed basking in the inverted position, with the ventral scales upturned. Ovulation is not noticeable in Children’s Python (Antaresia childreni) and determining if the female is gravid is not easy. This species generally has good muscle tone and by running the females through the fingers it may or may not be possible to feel the presence of eggs/ova. If the female refuses food and lies in the inverted position it is a good sign that she is gravid.
Egg Laying
Eggs are laid in spring in either laying boxes provided for the purpose or under the Eucalypt bark hide. A shallow depression in the substrate is formed by the female several days before laying. Ice-cream containers of damp sand and sphagnum moss or vermiculite mixture with an entry hole cut out of the lid are provided after the pre-laying slough when it is determined that the female is gravid.
After laying the female will gather the eggs together into a clump and incubate the eggs if permitted to do so.
Incubation
All clutches have been artificially incubated, as the cages are considered too dry to allow the female to incubate the eggs. The wood construction of the cages does not allow misting to maintain the high humidity necessary for maternal incubation. The same cages can however be used to incubate the eggs in plastic containers such as “Click-clacks” or bread containers. This was the method used before an incubator was built: a position in the cage that would hold a temperature of 27-32 deg C was selected and the plastic container with eggs would occupy the same cage as the adult until hatching.
On the day of laying the egg clump is removed from the female and each egg is separated, weighed, and measured before being placed in the vermiculite medium in the egg container. A water vermiculite mixture of 1:1 by weight is used in the containers (Barnett, 1981). Sometimes eggs cannot be separated from the clutch after they have hardened in the air and stuck to the clump. If it was considered that the eggs could not be separated safely without tearing the shells, then the clutch was incubated in a clump in the incubating containers – half-buried in the vermiculite medium. A moistened paper towel was sometimes placed and left on the top of the clutch to prevent the top eggs from becoming desiccated. The eggs are not in direct contact with the vermiculite and sometimes become dehydrated. The top eggs can access moisture from the wet paper towel, however some become sunken and remain that way throughout incubation before hatching normally. It appears that eggs will reach an equilibrium with their surroundings. Sudden changes in the temperature and humidity regimes should be avoided during incubation. The eggs on the bottom of the clump that are buried in the vermiculite will also absorb too much water and become turgid. It is much easier to incubate eggs if they are separated at laying and placed into incubation individually. If one egg dies it is easy to remove when they are separate, if it is attached to the clump and dies then it may need to be cut away or left in place. Sometimes eggs can become mouldy and decompose without affecting neighbouring eggs in the clump. At other times infection can spread from egg to egg and affect the entire clump, with only a small percentage of eggs hatching.
Eggs are incubated at 30 – 32 deg C +/- 1 deg C. At laying the eggs are marked on top with a lead pencil rather than an ink pen or texta which may be toxic to the embryo. Graphite from a pencil is harmless to eggs, they can be marked on top with numbers without concern. The eggs must not be rotated during incubation, if they are removed from the container they should be placed back in the same position with the marked side upright. Eggs can be removed from the containers and handled for inspection without harm to the developing embryos.
Sudden shocks or quick movement of the eggs should be avoided. Containers are not sealed for incubation but are opened regularly, once or twice weekly to inspect eggs and remove any that have died. The air in the container should be regularly exchanged by waving the lid over the eggs and re-mixing the incubating medium. Water will migrate around the incubator container in response to temperature differentials, often accumulating at the ends. Periodic re-mixing of the medium will avoid the vermiculite becoming too dry around the eggs.
Hatching
In the last two to three weeks of incubation it is normal for the eggs to lose moisture and appear dehydrated. It is not necessary to add more water at this stage. The container should be ventilated before hatching commences to provide plenty of fresh air for the hatchlings. When the first egg is cut by the egg-tooth of the first snake emerging then all the other eggs are opened using a curved pair of nail scissors. A small incision is made about 10-15 mm long on top of each egg. The young may take one or two days to emerge from the eggs after their heads have appeared. The entire clutch should hatch within a week.
Neonates
Upon hatching all neonates are removed to individual plastic containers measuring 23 cm long by 16 cm wide by 8 cm high. Ventilation holes are drilled into the clear plastic lids. Aquarium gravel is used as a substrate in these containers and changed as required. A small plastic water bowl is used along with a piece of Eucalypt bark as a hiding spot. During the cooler months of the year when the temperature in the room is cool the containers sit on a heat tape on one end of the container which is set at a thermostatically controlled temperature of 32-35 deg C.
Feeding is not attempted until the hatchlings have their first slough at about two weeks post hatching. Some specimens will take live pink mice as a first meal, the remainder will require mice scented with natural prey items such as skinks and geckos. This species appears to be more difficult to entice to accept pink mice than the Eastern Children’s Python (A. maculosa). Hatchlings of Children’s Python (Antaresia childreni) are generally smaller and much fussier with what food will be initially accepted. Clutches also vary according to maternal factors, some females produce clutches where most hatchlings will readily accept unscented mice, other females produce clutches of very stubborn feeders. Various methods have been used to entice hatchlings to feed on pink mice. Once hatchlings accept mice as food they are given these at subsequent feeds to avoid specimens developing a preference for natural food such as skinks.
Some specimens will require a live skink or a gecko to be rubbed on a mouse before they will accept it. Others require a small piece if skink tail about 2 mm long to be placed in the mouth of a dead pink mouse before they will accept it. Specimens that refuse all food are assist-fed on adult mice tails until they accept their first meals. By keeping a container of mouse tails in the freezer and thawing them in warm water prior to feeding a large number of hatchlings can be fed in a short period of time. The mice tails are cut at a 45-degree angle at the base, this allows easy entry to the mouth of the snake. The hatchling generally opens it’s mouth readily and the mouse tail is inserted about half way down the throat. Upon release most hatchlings will eat the tail on their own. Others may regurgitate the mouse-tail, if so the process is repeated. The backward pointing hairs on the tail make it difficult for the hatchling to regurgitate the food item. Baby eels (Elvers) were used some years ago until they became unavailable. They were a good source of food for baby snakes, particularly small venomous snakes.
Assist feeding may be required twice weekly for about 10-12 feeds until all young Children’s Pythons will feed voluntarily. The odd recalcitrant feeder will be encountered but after 6-8 weeks all young should be readily accepting dead pink mice. Juvenile growing pythons are generally fed one pink or fuzzy (haired) mouse twice weekly. The water bowl is changed weekly as with the adult snakes.