By MERRILL WITT
On Mon 19 March, the Total Environment Centre’s Urban Sustainability Campaigner, Saul Deane, told ABC radio Breakfast hosts Wendy Harmer and Robbie Buck that the growing southwestern Sydney koala population is at risk of being wiped out.
Vast swathes of rural land from Campbelltown to Wilton are being rezoned for up to 60,000 new houses, despite the fact that in the 1970s the region was set aside as part of a green belt around Sydney.
Deane believes that the original planning strategy was visionary because in the intervening years it allowed the largely undisturbed region to be “reclaimed by the koalas at a time when they were disappearing in other parts of Sydney.” Today, the area is home to a thriving and healthy population of 500+ koalas.
Understandably, environmentalists and community members are baffled about why land is being released for development before adequate national koala parks and corridors are designed and established.
Koala’s survival as a species is at risk
Rezoning could prove to be a high-stakes decision that the NSW Government comes to regret. “The survival of the entire koala species in the country may hinge on preserving Sydney’s koalas,” Deane told Harmer and Buck.
Deane’s timeslot on the 702 Breakfast show was followed by Dr Norman Swan’s latest update on the coronavirus. When the phones finally lit up with listener’s calls, understandably all anyone wanted to talk about was the pandemic’s devastating impact on our health and economy.
But we do need to have an urgent conversation about how our koalas and other native wildlife are coping or not coping with environmental threats. Jim Robbins, writing for The New York Times in 2012, said that diseases don’t just happen, “they are a result of things people do to nature.”
For years, researchers around the world have been investigating what is called the “ecology of disease.” Before it was dismantled by the Trump administration in 2018, the United States Agency for International Development, for example, funded a project called Predict. It brought together veterinarians, conservation biologists, medical doctors and epidemiologists to study how encroachments on natural environments, like a new road or a mine, can increase the risk of diseases in animals that are likely to spill over into humans.
Evidence from this initiative and others about the underlying causes of disease is so convincing that Peter Daszak, a leading US scientist and president of the EcoHealth Alliance, could confidently tell The New York Times in 2012 that “any emerging disease in the last 30 or 40 years has come about as a result of encroachment into wildlands and changes in demography.”
Environmental damage cause of disease in koalas
In Australia, researchers have discovered that loss and degradation of koala habitat from urban development, logging and agricultural activities have made koalas susceptible to the sexually transmitted disease chlamydia and a virus similar to the human immunodeficiency virus (HIV).
According to a recent study published in the Journal of Virology, koalas infected with koala retrovirus type B are more likely to suffer some of chlamydia’s most severe side-effects, like conjunctivitis, cancer and sterility.
An estimated 70 percent of koalas in Australia have chlamydia. Fortunately, at least for now, the Macarthur bushland koala population in southwest Sydney is chlamydia-free.
Retired researcher Dr Robert Close, who studied koalas in the region for over 24 years while at the University of Western Sydney, told the ABC that the area is attractive to koalas because the Cumberland plain woodlands support healthy vegetation. “It gives them a great range of eucalypts to shelter on,” he says.
Relatively easy access to healthy water sources like the Nepean and Georges rivers has also helped a population that started small to grow steadily. Dr Close said his study revealed that “once the females established themselves, they didn’t die till old age and they gave birth to a cub at least once a year.”
While the southwest Sydney koalas are not immune to human threats like roadkill, the success of the colony to date highlights how preserving the environment is key to their health and future survival.
Unfortunately, this urgent message doesn’t seem to be getting through to our leaders. Despite mounting evidence to the contrary, most governments around the world are either failing to understand or refusing to acknowledge that human, animal and ecological health is inextricably linked.
Pandemic outbreaks are near-certain in future
Researchers from the Wuhan Institute of Virology in China were quick to identify the novel coronavirus or COVID-19 as zoonotic, having originated in bats. In fact, it’s the sixth bat-borne virus in 26 years that has severely impacted human health – the five others being Hendra in 1994, Nipah in 1998, SARS (severe acute respiratory syndrome) in 2002, MERS (Middle East respiratory syndrome) in 2012 and Ebola in 2014.
After rodents, bats are the biggest carriers of viruses and, like koalas, they are facing a range of environmental threats that are making the chance of them spreading disease a lot more likely. Dr Shi Zhengli, the Wuhan Institute’s leading virologist and an expert on bat diseases, recently told Jan Qui of Scientific American that “with growing human populations increasingly encroaching on wildlife habitats, with unprecedented changes in land use, with wildlife and livestock transported across countries and their products around the world, and with a sharp increase in both domestic and international travel, new disease outbreaks of pandemic scale are a near mathematical certainty.”
Nationals MP Barnaby Joyce was rightly pilloried for suggesting that the best way to stop bushfires is to concrete everything. Likewise, attempting to reduce bat numbers to stop the spread of deadly viruses would be disastrous. Not only do bats promote biodiversity and support healthy ecosystems all over the world by eating tons of disease-carrying forest insects, they also pollinate many fruits like bananas, avocados and mangoes. Recent estimates suggest that their regular consumption of insects saves our agriculture industry billions of dollars a year in pest control alone.
For years, both the federal and NSW governments have been insisting that environmental concerns must be balanced against the needs of the economy. After the bushfire crisis, Scott Morrison’s claim that more aggressive action on climate change will jeopardise jobs and economic growth made little sense. In light of the unfolding coronavirus catastrophe, it just sounds absurd.
Fortunately, local community members and environmentalists have already presented NSW Environment Minister Matt Keane with a workable plan to stop Stage 2 of the massive Mt Gilead (Fig Tree Hill) estate from proceeding before the only wildlife corridor connecting the Georges and Nepean Rivers in the entire Western Sydney region can be protected.
Establishing a Koala National Park in the area, along with other essential wildlife corridors, is not just about saving Australia’s koala. It’s a critical step in the right direction to saving ourselves.