When is a dingo not a dingo? : hybridisation with domestic dogs

In this chapter we discuss the issue of genetic introgression in the dingo, exploring the various methods by which dingoes have been differentiated from hybrids in the laboratory and in the wild, and discuss the possible consequences of dingo hybridisation from both an evolutionary and ecological perspective. In doing so, we highlight several areas for priority research so that the impacts of hybridisation can be better understood. Prior to doing that, we provide an overview of what a dingo is, and what sets it apart from other dogs in terms of its biology. By definition, the dingo is a primitive canid that was introduced to Australia by Asian seafarers 3500-5000 years ago. In that time, it has had a major influence in shaping Australian ecosystems and now plays an important role as a top-order predator. Since European settlement some 200 years ago, its conservation status has changed greatly, through persecution in areas not only where it has had an impact upon domestic stock but also through interbreeding with domestic dogs. Over the same period the clearing of land for grazing and cropping in some areas has also reduced the availability of suitable habitat and native prey species for the dingo, contributing to its decline. The degree of hybridisation varies across the continent, with higher levels in more closely settled landscapes such as in south-eastern Australia. Hybridisation has led to changes in the morphology of animals, particularly appearance such as coat colour, and increased variability in anatomical features of the skull. There are also data suggesting the average body mass of wild dogs may be increasing in such areas. This may have an impact on the way in which hybrids interact with their prey resources, but this needs to be more closely examined in the wild. Otherwise, hybrid animals appear to behave in similar ways to dingoes, including aspects of social behaviour such as pack formation, reproductive cycles and broad feeding habits. Conservation management of dingoes will be difficult if based on genetics alone. Instead, it will be more practical to manage for animals that are mostly dingo by way of genetics, but otherwise provide the same function in the landscape. Regardless of genetic status, the conservation of dingo-like animals will need to be balanced against a range of other issues, particularly in agricultural zones. Informing the Australian public about the changing face of the dingo will be equally important to achieving the goal of maintaining these animals as functional components of landscapes.