Is it time for Tasmanian devils to once again roam mainland Australia, after they went extinct there some 3,000 years ago? A new ecological impact study out of the University of New South Wales Australia (UNSW) suggests the answer may be "yes."
Culls of the mainland's dingo population in some areas, done to protect livestock, left a nature-abhorrent vacuum that was filled by red foxes and feral cats, which now cause trouble with native mammals and mess with the ecological balance wherever the dingoes once held sway.
To stop the fox and cat populations from spreading, then, the study wondered how the balance of nature might fare if indeed the devil returned. The latter creature was eradicated from the mainland three millennia ago, when it's theorized they were hunted out of existence by dingoes.
"There are large areas where the dingo is gone and we need a predator who can suppress fox numbers," explained the study's lead author Daniel Hunter, in a press release. "The devil is the obvious answer," said the PhD candidate from UNSW's School of Biological, Earth and Environmental Sciences.
The team used historical data about dingoes, devils, and foxes and then applied it to new models that sought to predict how different mainland ecosystems would react to the new presence of the devils.
The models showed that reintroduction of the devils would indeed result in decreased fox and feral cat populations, as well as fewer grazing herbivores such as wallabies, which eat vegetation that smaller animals use to hide from predators.
The researchers think this control of fox and cat populations would happen in the clearest of ways: direct attack on the animals and their young. "There is very good evidence from Tasmania that cats modify their movements and numbers are lower where there are healthy devil populations," said study co-author Mike Letnic, an associate professor at UNSW.
The scientists caution, however, that the return of the devils would not cure all ills. Threatened species that are currently in danger from fox populations did not see much benefit in the devil reintroduction models.
"Devils aren't a silver bullet, but we think that they could do a lot of good on the mainland, and this study indicates that a monitored process of reintroduction could actually work," said Letnic. "We need to take action to arrest the extinction crisis we have in Australia, and that requires being bold and trying something new."
The impact study has been published in the journal Biological Conservation.