It’s underwater now, but there used to be a land-bridge between mainland Australia and Papua New Guinea. A new DNA study shows dingoes migrated across this bridge between 8,000 and 10,000 years ago in two waves.
And genetically, the two groups are quite different – so we now know how to manage them separately, for conservation purposes. But how did we get to the point where dingoes need protecting?
“Apex predators are in decline, globally, which has lead to and threatens continuing impacts to entire ecosystems,” the study reads.
“On the Australian continent, indigenous apex predators went extinct thousands of years ago, leaving the dingo as the sole remaining apex predator on the mainland.”
These days dingoes are considered threatened, according to the researchers – who cite “lethal control programs, habitat fragmentation, and genetic dilution from hybridization with domestic dogs” as the major causes.
“Dingoes have been subject to hybridization pressure from modern domestic dogs brought by Europeans, particularly in regions where human populations are high,” they explain.
This means today, pure bred dingoes are quite rare.
The DNA study was led by scientists from UNSW and the University of California, and is the first to study the evolutionary history of dingoes around Australia using both mitochondrial and Y-chromosome genetic markers.
127 genetically pure dingoes across Australia, as well as five New Guinea Singing Dogs from a North American captive population made up the study. Y chromosome and mitochondrial control region data from 173 male dogs, including 94 dingoes, was also used.
The north-western group can be found in Western Australia, the Northern Territory, northern parts of South Australia, and central and northern Queensland.
The south-eastern group can be found in New South Wales, the Australian Capital Territory, Victoria and southern parts of Queensland (including Fraser Island).
The researchers now want a broad survey of dingoes in national parks and state forests so conservation efforts can be focused in key areas. Researchers also want state and federal legislation allowing fatal control measures be reviewed.
“Care should be taken not to move dingoes between the different wild populations,” says Dr Kylie Cairns from the School of Biological, Earth and Environmental Sciences at UNSW Sydney.
“And captive breeding programs should ensure the two dingo populations are maintained separately, with genetic testing used to identify ancestry.”
Inter-breeding with domestic dogs is also a big problem with dingo conservation. The south-eastern population is particularly at threat of genetic dilution along with habitat loss, and lethal control measures – such as baiting and the recently reintroduced wild dog bounty in Victoria.
“Effective containment or neutering of male dogs in rural areas may help achieve this reduction in inter-breeding,” says Dr Cairns.
“Additionally, baiting and culling practices break apart dingo packs, leading to increased incidences of hybridisation.”
Dr Cairns says alternative livestock protection measures need to be explored – like livestock guardians, predator deterrents and improved dingo-proof fencing.