Dingoes 'Rewilding' Australia Could Save Biodiversity, Say Experts
Australia is famous for its incredible biodiversity and unique animal species. However, it is likewise infamous for an exceptionally high rate of extinction. In fact, the continent has lost one in 10 of its native mammal species over the last two centuries - the highest extinction rate of any nation in the world. Now, experts are proposing that "rewilding" parts Down Under with native dingoes could help prevent die-offs in the future.
Dingoes are free-ranging canines believed to have once originated from East or South Asia as semi-domestic before adapting back to a wild lifestyle once arriving at Australia. Classified as a subspecies of the grey wolf (Canis lupus), the dingo is considered a 'native' and essential member of current Australian ecologies, despite its foreign origins.
However, as things stand, the species is not nearly as prevalent as it once was. Hunting and trapping have done their part in dingo suppression, but the largest cause behind the animals' vulnerable status may be the Dingo Barrier Fence (DBF).
At a little under 3,440 miles long (~5530 km), the DBF stretches from eastern Queensland all the way to the South Australian coastline, earning it a place in the Guinness Book of World Records. The fence was erected between the late 1800s and early 1900s to protect cropland from rabbits, but was later modified to protect imported livestock such as sheep from the vicious canines.
Tiny Top Predators Invade
However, ecologists are now making the argument that the DBF is doing more harm than good, keeping these top predators out of specific regions that are now overrun by smaller invasive predators like feral cats and red foxes.
Intercontinental sailors used cats to help keep on-board rat populations in check, while red foxes were brought over to Australia for hunting purposes. Unfortunately, both species proved too good at their job, spreading rapidly after preying on the many perfect "meal-sized" mammals that Australia is home to. Recent research has even directly tied these invasive mid-sized predators to Australia's alarming rate of extinction.
"We knew it was bad, but I think our tallies were much worse than previously thought," research lead John Woinarski, of Australia's Charles Darwin University, told The Associated Press just last week. "The fact that we're losing such a large proportion of our species is a problem of international importance." (Scroll to read on...)
Still, things aren't as hopeless as they may seem. A massive team of researchers from Australia, New Zealand, and the United States recently teamed up to propose that dingoes be reintroduced to rangeland past the fence. The hope is that they would bully and even prey on these smaller problematic predators, reducing their numbers even as the dingoes reestablish themselves.
They detailed their argument in the journal Restoration Ecology.
Lessons From Wolves
Researcher Thomas Newsome, Chris Dickman, and Euan Ritchie, who were involved in the work, even press that the reintroduction could start in the western portion of New South Whales (NSW).
"Western NSW is greatly degraded and suffers from eroded soils, impoverished native vegetation communities, and unprecedented levels of extinction of native mammals and other vertebrates," the trio recently wrote in The Conversation. "Dingoes are absent, or found in very low numbers, across much of central and western NSW, as well as parts of South Australia... so reintroducing dingoes could help start restoring these damaged lands."
They add that there is reason to hope this dream becomes a reailty based on observations of grey wolf reintroduction in the United States. Past studies of grey wolf recovery have shown that since the apex hunters have begun to return to long-abandoned US regions, ecological balance is getting back in order, with overgrazing deer and elk being reduced to sustainable numbers even while overpopulated predators like the coyote are bullied back to smaller territories. This likewise has left smaller native predators unthreatened by the wolf recovery as well. (Scroll to read on...)
The trio and their colleagues argue that based on previous ecological observations, the dingo would help control overgrazers (resulting in soil erosion) as well, even as they cull cat and fox populations.
Still, in the United States not everyone is happy about potential livestock killers returning to their state. In Australia it would be no different, with the research team expecting strong opposition to the plan from farmers.
What's more, it's actually unclear if dingo rewilding will do what some are promising. Another study published in the journal Biological Conservancy back in 2013 cited numerous examples about how the ecological role of the dingo in Australia is just about as "clear as mud."
But that, Newsome and his colleagues argue, is where the DBF can prove its worth.
Move That Fence!
"In our new paper we argue that we can resolve the debate by moving the dingo fence around Sturt National Park in western NSW, on the border with Queensland and South Australia," they explain. "The park is currently on the inner side of the fence, where dingoes are uncommon. Our proposal would put it on the outside, where dingoes are more common." (Scroll to read on...)
The park is not traditional grazing ground, meaning that the introduction would be no threat to livestock, yet could still provide experts with a way to observe the effects of this "rewilding." The results would then provide more material for further discussion and consideration of dingo reintroduction on a larger scale.
"The major prerequisite for the experiment to proceed would be convincing local communities to support the effort," the trio added. "That support would likely help to sway government policy, and garnering this support would require effective community engagement and extension."
But first, they need evidence that everyday citizens, not behavioral ecologists alone, can interpret. In that light, simulations and conclusions drawn from US studies won't cut it.
The experts calculated that to start their work, 275 km of new DBF would be required - crafting an isolated experimental bubble into Sturt.
"Monitoring costs would be in the order of A$1 million per year ($782,000 USD), which is about 10 percent of what is spent maintaining the dingo fence each year," they explained.
And while that sounds costly, it really isn't so bad considering that the Australian island state of Tasmania alone spends over a whopping $27 million (USD) to keep invading red foxes in check.
"There is an urgent need to develop bold solutions to help revive our native mammal populations," the researchers press, adding that "to determine if the dingo can help, a dingo reintroduction experiment is the best way forward."
For more great nature science stories and general news, please visit our sister site, Headlines and Global News (HNGN).
- follow Brian on Twitter @BS_ButNoBS.