Breeding and Care of Stimson Pythons (Antaresia stimsoni)

Stimson Python (Antaresia stimsoni)



The Stimson Python or “stimmy” as it is often referred to in the reptile hobby has two currently recognised subspecies with the likely hood of there being a third (Pygmy stimson) being added in the near future. Antaresia Stimsoni inhabits the western half of Western Australia and Antaresia stimsoni orientalis is distributed from central Western Australia through the lower two-thirds of the Northern Territory into north-eastern South Australia, north-western New South Wales and the interior of Queensland. They were named after Mr. Andrew Stimson of the Zoology Department at the British Museum of Natural History.

These snakes are among Australia's smallest pythons with an average adult length of about one metre. They are a robust species with a long broad head that is slightly wider than the neck. Dorsal colouration consists of yellowish brown, pale brown to grey or whitish. There is a persistent pattern of dark brown to reddish brown, smoothed-edged blotches that are circular or elongated. A dark streak is present from the nostril through the eye to the side of the neck. The underside is white with an opalescent sheen. Both sexes have small thin cloaca spurs and the tail is prehensile.

Usually found in association with sparsely vegetated, rocky outcrops within woodlands, grasslands and drier forests. Most commonly shelters beneath exfoliating rock slabs but also seeks refuge in rock crevices, hollow logs, termite mounds, abandoned burrows and caves. This species like other members of the "Children's Python complex" is well known for regularly entering caves to prey on bats. They also feed on small birds, frogs, lizards and other small mammals. The Stimson's Python is essentially nocturnal, though sometimes forages and basks during the day.



Housing for adult Stimson pythons is best provided with melamine or wooden enclosures with glass fronted doors and measure a minimum of 90cmL x 50cmD x 30cmH. Heat should be provided by a heat mat or cord connected to a thermostat and be set to 34 degrees Celsius with a gradient in the enclosure that ranges from 30 to 22 and never below 18 degrees Celsius for long periods.

Substrate can consist of a few different options from paper towel, newspaper, butchers paper, eucalyptus mulch, cypress mulch, washed beach sand or red sand. You can purchase many of these from your local pet shop or hardware store.

Stimson's Pythons will benefit from a hide place over the heat source and should be of a size that allow the animals to fully enter and fill the hide to allow it to feel secure. A water bowl should be placed in the cool end that is spill proof and large enough for the animal to soak in if they choose to. A small climbing branch can be offered and should be changed occasionally to offer some environmental enrichment.



Stimsons are introduced to one another during May, June, July and August. Most mating activity has subsided by the end of August. The male should always be introduced to the females enclosure and will respond by seeking and searching the enclosure for his female counter part. Mating usually occurs within 1 to 2 days after the introduction. Once a pair have accepted one another mating may last for several hours or more and often the longer the breeding the better the results. An otherwise disinterested male may be stimulated to mate the female by introducing and removing 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.



After the mating season females will often become reclusive and hide from view. During late July and August females are often observed basking in an inverted position with their ventral scales upturned. Ovulation is not noticeable in A. stimsoni 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. Eggs are laid in spring in either laying boxes provided for the purpose or under their hides. Once it is determined that the female is gravid, small plastic containers of damp sphagnum moss with an entry hole cut out of the lid or side are provided after the pre-laying slough. After laying the female will gather the eggs together into a clump and incubate them if permitted to do so and I have success leaving mother nature to run its course.



If you choose to artificially incubate you will need to be prepared by having your incubation tubs setup with water and perlite mixed 1:1 by weight to water and have enough to fill 3-5cm of the bottom of the tub and enough room to place the lid on without touch the top of the eggs. Once the egg clump is removed from the female and each egg it can be placed in the perlite in the egg container. Sometimes eggs cannot be separated from the clutch after they have hardened in the air and stuck to the clump and will need to remain together.

Sudden changes in the temperature and humidity regimes should be avoided during incubation. A small 5mm hole can be drilled at each end of the tub for some air flow and eggs can be checked weekly and any eggs that have died or are decaying can be removed.

Eggs are incubated at 31°C and must not be rotated during incubation and if they are removed from the container they should be placed back in the same position. 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.

In the last 2-3 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 hatchling 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 1-2 days to emerge from the eggs after their heads have appeared. The entire clutch should hatch within 4-7 days.



Once all neonates have hatched they can be removed to individual plastic containers measure 25 cm long by 15cm wide by 8 cm high. Ventilation is important and holes should be added to the front or top of the tubs. Paper towel is used as a substrate in these containers and can be changed as required. A small plastic water bowl is used along with a small plastic lid for hiding spot. The containers can be heated with heat tape or cord at one end which is set at a thermostatically controlled temperature of 32-35°C

Feeding should not be attempted until after the hatchlings have their first slough at about two weeks post hatching. Some specimens will take pink mice as a first meal, the remainder will require mice scented with natural prey items such as skinks and geckos. Hatchlings may require a live skink or a gecko to be rubbed on a mouse before they will accept it. Others require a small piece of skink tail about 2mm long to be placed in the mouth of a dead pink mouse before they will accept it. You can also expose some of the brain matter of a dead pinkie mice to entice the young to eat. If all else fails then force feeding of either mice tails or day old pinkie mice will need to take place until the animal accepts food on its own.