Endangered Species Breeding Programs
Tidbinbilla manages highly successful breeding programs for the critically endangered Northern Corroboree Frog, the Southern Brush-tailed Rock-wallaby and the Eastern Bettong on behalf of the ACT Government.
Tidbinbilla plays a vital role in the conservation and reintroduction of the Tasmanian or Eastern Bettong (Bettongia gaimardi). Along with its partners (Environment and Planning Directorate, Mulligans Flat Woodland Sanctuary Board of Management, the Tasmanian Department of Primary Industry, Parks, Water and the Environment (DPIPWE), Australian National University Fenner School of Environment and Society, CSIRO, and James Hutton Institute in Scotland) Tidbinbilla’s mission is to eventually reintroduce eastern Bettongs into the wild. A small macropod (part of the Potoroidae family) that was once found in the Canberra region now only resides on the eastern half of Tasmania and has only been found there for the last 100 years or so. This is due to land clearing for farmland, overgrazing, predation by introduced species such as foxes and competition from introduced species such as pigs. In 2011 Tidbinbilla acquired a number of eastern bettongs from the wild in Tasmania, These were the first animals to step foot onto ACT soil in over 100 years. These animals were then quarantined and after more animals were brought in animals were then transferred to Mulligan’s Flat Woodland Sanctuary to be reintroduced into a large predator proof area. Since 2011 Tidbinbilla has seen a huge success in its breeding program. Tidbinbilla has been able to retain important genetic diversity, provide an insurance population for Mulligan’s Flat and also provide important information about the species itself. Bettongs play a vital role in ecosystem heath. They eat underground fungi or hypogenous fungi that help with nutrient exchange between the soil and plants. By eating the fungi they are able to disperse the spores through their faeces and therefore increase the amount of hypogenous fungi. When they find the underground or hypogenous fungi they create diggings that allow more water to be retained in the soil.
Northern Corroboree Frog
Tidbinbilla Nature Reserve in Australia boasts the largest captive breeding program for the critically endangered Northern Corroboree Frog (NCF), of which less than 1000 remain in the wild. The Northern Corroboree Frogs held at Tidbinbilla are all from the Southern Brindabella Mountains, which are genetically distinct from other NCF populations. There are estimated to be less than 50 wild individuals remaining in the Southern Brindabella Mountains. Staff at Tidbinbilla have released around 200 captive-bred individuals to the wild each year, with 600 being released in 2014, to help bolster wild populations. It is hoped that these release efforts will allow breeding populations to persist in the wild and have the opportunity to develop resistance to the introduced Chytrid fungus pathogen. This fungus is well established in the alpine sphagnum bog environment where the frogs are distributed, and is the primary cause of decline for this species, and many other species of frogs worldwide.
Tidbinbilla Nature Reserve maintains a captive population of around 800 - 1600 individual NCF’s, including around 250 adult breeding frogs which were collected in 2003 from the wild as eggs and raised at Tidbinbilla. These eggs collected from the wild in 2003 were used to establish the breeding program, and are still the primary breeders, although in 2012 the first generation of captive-bred individuals (offspring from the original wild-sourced breeders) attained maturity and successfully bred, thus producing second-generation captive-bred frogs.
This success continued in 2013 with more second-generation captive-bred eggs being produced.
There have been four releases so far of captive-bred NCF’s to the wild, in 2011, 2012, 2013 and 2014. The frogs are released at one year of age and their individual ventral pattern is photographed for identification purposes. The wild population is also audited yearly to monitor the rate of decline or any spikes in the population. Whether any captive-bred frogs have survived will not be known until the released frogs reach sexual maturity and begin calling, because breeding calls are the only way to monitor these very small 2-3cm frogs in their sphagnum moss habitat. NCF’s reach sexual maturity at 4-5 years of age, and thus the first released frogs have only just reached breeding age in 2014/2015. During the 2015 audit we heard 9 calling male Corroboree Frogs (female Corroboree Frogs don’t call), which represents about 10% of the frogs released in 2011. Whilst this number is not high, to put it into perspective we haven't heard that many Corroboree Frogs calling in the ACT for about a decade. Importantly, it shows that it is possible for captive-bred frogs to survive for several years in the wild where Chytrid Fungus is present, to reach breeding age. The next step is to determine whether these captive-bred survivors will breed in the wild.
Further information on Corroboree frogs can be found on the national Corroboree Frog website: www.corroboreefrog.com.au/
Southern Brush-tailed Rock-wallaby
It is estimated there is less than 40 Southern Brush-tailed Rock-wallabies left in the wild in Australia. Tidbinbilla currently has approximately 70% of the captive breeding population in Australia. 2014 was an extremely successful year with a 18 joeys being born which is on par with our record breeding year in 2012. Since 2010, Tidbinbilla has successfully bred 72 joeys, 26 captive-bred Southern Brush-tailed Rock-wallabies have been released into the wild in Victoria as part of a national recovery breeding program being undertaken between several agencies including the ACT Government (Tidbinbilla), Victorian Government (Department of Sustainability and Environment), Parks Victoria, Adelaide Zoo, Waterfall Springs Sanctuary and Mt Rothwell Biodiversity Centre. At the rock-wallaby habitat you may be lucky enough to catch sight of this shy wallaby basking on a rock.
Behind the scenes tours offer a unique insight to both of these programs as part of the Tidbinbilla Discover our Wild Side tour.
Note there may be additional species bred in the near future.