It's been a busy week -- full of both good news and bad -- for Australia's endangered species.

One of the country's most endangered mammals, the Victorian brush-tailed rock wallaby (Petrogale penicillata) now has a chance at survival thanks to an innovative breeding program at Adelaide Zoo. The process takes days-old joeys and transfers them to the pouches of mothers of a similar species, allowing the original mother to start breeding again. Only a dozen Victorian brush-tailed rock wallabies existed before this breeding program, but the zoo reports 130 successful births, a more than 1,000 percent increase in the species' population.

The critically endangered Northern hairy-nosed wombat (Lasiorhinus krefftii) has also seen a small population boost, from 115 animals to 138, over the last two years. The wombat lives in just a single site in Epping Forest National Park in central Queensland, but a AU$3 million ($2.35 million USD) partnership with the mining company Xstrata will soon create a site for a second habitat, which would help protect the species from threats such as disease or fire, which could otherwise wipe out the wombats in a single stroke. Previous conservation efforts -- such as building a predator-proof fence and feeding the wombats during droughts -- have been credited for the species' recent population growth.

But the news isn't as good for the golden-backed tree-rat (Mesembriomys macrurus). The species has only been observed scientifically three times in the last century, and now an extensive search in Australia's Northern Territory has failed to turn up any trace of the species. It's now feared the species may be extinct in NT, if not in all of Australia.

And then there's the dingo. Feared and hated throughout much of Australia as a livestock-slaying pest, the pure-bred dingo (Canis lupus dingo) is rapidly disappearing from the country as the species cross-breeds with domestic dogs. One of the last pure-bred populations of dingoes exists on Fraser Island, where dogs are not permitted.

But local authorities have taken a hard line on dingoes over the last few years, since the 2001 mauling death of a nine-year-old boy. According to The Courier Mail, 11 "problem" dingoes have been killed in the past 12 months, including four in the past month alone. Since Fraser Island is home to just 100 to 200 dingoes, this has scientists worried that the pure-bred dingo could soon be a thing of the past, and the species could soon disappear altogether. Fraser Island Dingo Preservation Society chairwoman Bree Jashin called the deaths a "dingo genocide," and has called for changes to the island's dingo management team.

Finally, the Australian government has finally officially declared the Tasmanian devil (Sarcophilus harrisii) to be an endangered species. A transmittable cancer called Devil Facial Tumor Disease has wiped out 60 to 70 percent of the world's Tasmanian devils in the last 10 years. Aussie Environment Minister Peter Garrett says that "strong action is being taken to find out more about this disease and to stop its spread," and this designation offers greater protection to devils in Australia and on their island home of Tasmania.

Image: Map of Australia, via Wikipedia