DNA analysis finds little interbreeding with domestic canines.
A new study has found that most Australian dingoes have pure dingo ancestry, certifying their importance as native apex predators rather than pests.
The research, published in the journal Australian Mammalogy, found virtually no feral dogs across the continent as commonly thought and very little evidence of interbreeding between dingoes (Canis lupus dingo) and domestic dogs (Canis familiaris).
“The results challenge the widespread use of the term ‘wild dog’,” says lead author Kylie Cairns from the University of New South Wales.
“I think that moving forwards it is important that governments, wildlife managers and agriculture industry groups use the name dingo to describe these wild canines because this is what they are.”
Technically, dingoes – which include New Guinea singing dogs – are part of the canid family. But their lineage, thought to diverge 8000-12,000 years ago from their ancestral population, is distinct from domesticated dogs.
Contrary to the latter dogs, Cairns and colleagues explain in their paper, dingoes are truly wild-living animals that don’t rely on food and water from humans or human settlements.
But there is growing concern about interbreeding – hybridisation – between wild and domestic canids, which could weaken the genetic identity of dingoes.
“Hybridisation can be a problem between wild and domestic animals or two species of wild populations,” says Cairns, “because it can change or alter the identity and biology of the species, ‘diluting’ the wild population into extinction.”
Hybridisation is not all bad – it’s helped some species to adapt to changing climates or gain disease resistance. But there is concern that wild dingoes have interbred with dogs to such a degree that they’re virtually extinct.
animal, as our largest mammalian predator,” says Cairns, “and they are culturally important to First Nations Australians.”
Previously, understanding of dingo hybridisation with dogs was based on unreliable observations from skull morphology and physical appearance. The resulting uncertainty has led to confusion about their status.
In Victoria, for instance, dingoes are listed as a threatened species, but wild dogs – defined as feral or wild populations of domestic dogs or dingo/dog hybrids – are declared a pest.
To shed light on the matter, Cairns and colleagues used microsatellite DNA testing, which was introduced in 1999 and is now used by wildlife managers and conservation groups, increasing the sample size from previous assessments.
They analysed data from 5039 samples and location coordinates from three datasets of wild-roaming canids across Australia, collected by trappers, wildlife managers and government agencies, to analyse their genetic ancestry.
Analyses identified only 31 (0.61%) samples as likely feral dogs and 27 as dingo x dog hybrids, suggesting that self-sustaining feral dog populations are scarce and that interbreeding occurs rarely.
The team notes that their results are supported by the rarity of genuine feral dogs globally, even when opportunities for crossbreeding arise.
“The finding that there are very few feral dogs in the wild suggests that there is something ecologically and biologically different between dogs and dingoes and that really an animal must be mostly dingo to survive in the wild,” says Cairns.
They did find higher levels of dog ancestry in south-eastern Australia, which raises concerns about the widespread use of aerial baiting in this region and its potential impact on dingo populations.
“We know from other wild canids like coyotes, wolves and red wolves that lethal control can increase the likelihood of interspecies hybridisation because it breaks apart social groups and reduces the number of available mates,” Cairns explains.
“If we wish to conserve our native dingoes and limit future dingo/dog hybridisation then widespread lethal control shouldn’t be used in conservation areas during the dingo breeding season.”
Currently, dingoes are widely killed across Australia with aerial and ground 1080 baiting programs, including National Parks. Yet Cairns notes there are non-lethal methods to manage them such as electric fencing and livestock guardians.
The team calls for greater public awareness of current practices and consultation on dingo management, which has been dominated by the agricultural industry. Changes in terminology would be an important first step.
“[T]he term dingo needs to be reinstated because genetic testing demonstrates that a majority of animals are of high dingo ancestry and feral dogs are virtually absent,” they write.
“The term wild dog does not reflect the ancestry of wild canids in Australia and is poorly understood by the public, it should be retired from use.”