Conservation Programs

Captive bred Woma Pythons from Adelaide Zoo were used in one of the first experimental releases of captive bred snakes in Australia for a trial release in the Arid Recovery Reserve.

Pythons and boas are a group of snakes that are of particular conservation concern throughout the world so this project has provided important information for future conservation efforts.

Pythons and boas are a group of snakes that are of particular conservation concern throughout the world. In one of the first experimental release of captive-bred snakes in Australia, woma pythons were introduced into the Arid Recovery Reserve in northern South Australia. This release of woma pythons is not only important for conservation of Australian wildlife, but allows us to learn how best to release other endangered snakes elsewhere in the world.

The woma is a large terrestrial python endemic to Australia’s arid zone. They grow to 2.5m in length, and live mainly in sandy habitats, including the Simpson Desert and Moomba region of South Australia. They previously occurred in the Roxby Downs region but have become locally extinct, possibly due to fox and cat predation of juveniles. There have also been other declines in range and abundance of this animal in the State.

These womas were bred at Adelaide Zoo in 2003, as part of a captive breeding programme. They were quarantined to ensure that they did not carry unwanted diseases into wild reptiles. Radio transmitters were surgically placed in the snakes to allow monitoring following the release.

The release, on September 22, 2007 saw nine of the snakes join the growing list of Australian native animals thriving within the reserve. With five of the snakes undergoing a ‘hard release’ and the other four a ‘soft release’, it provides a perfect opportunity to compare release methods for these pythons.

The woma release provided new insights into woma biology, and the changing ecology in the Arid Recovery reserve. Eight of the nine woma pythons released in the reserve were predated by Mulga Snakes within three months of the release. The other woma simply went missing. This result was completely unexpected.

It is not clear whether the abundance of Mulga snakes in the Arid Recovery Reserve is different from surrounding areas. Certainly the abundance of native mammals is higher in the reserve than in surrounding areas. Outside of the reserve the mammals are reduced by changes to the habitat brought by rabbits and increased predation by introduced foxes and cats. What we know about Australian deserts is from studies done in areas that have been severely affected by introduced mammals, and may not represent the natural ordr of things. It is only in places like Arid Recovery reserve, were feral animals have been removed, that we can get a better idea about how Australian deserts work under more natural circumstances.

The release and monitoring program was a milestone in the history of the Arid Recovery Project because it was the first time a native predator is reintroduced into the reserve. Womas are a natural predator of reintroduced greater bilbies and possibly burrowing bettongs and their introduction to Arid Recovery is aimed to both assist woma conservation and help regulate reintroduced mammal populations to more natural levels. However, unlike foxes and cats, they are unlikely to threaten any of the reintroduced mammals because they only feed occasionally.

“It was always a trial release, no-one knew what would happen, now that we do we know we’re going to have to change tact a little bit and try a different approach” said Dr John Read (spokesperson for Arid Zone Recovery).

“This will lead to more studies of wild womas and looking at the numbers of mulgas within the reserve, and we know there are at least three large mulgas in the area where we released the womas”.

Dr Read said the project has also given researchers the chance to study the movements and habits of mulgas, thanks to the many volunteers who checked on the womas every day.

“Most people assume that womas would be immune to mulga venom, so if nothing else we have proven this is not the case. We even found that one of the mulga snakes was the same size as the woma, which is bizarre because I would have expected a really large woma to eat the mulga”.

Donations towards in situ reptile conservation are raised through Adelaide Zoo’s Boileau Behind the Scenes Tours. Come and visit our reptiles on the “Rapt in Reptiles” tour, learn more about them directly from their keepers, and personally contribute towards reptile conservation.