Because it threatens livestock, the native dingo Canis dingo is classified as a pest species. Barrier fencing and lethal methods are used to control the dingo, which is one of the few remaining mammalian top predators in Australia. Dingo management therefore parallels persecution of the Tasmanian tiger: a top-predator that was hunted for its alleged impact on livestock. Dingo persecution has reduced the species' distribution and disrupts its social structure, potentially accelerating the demise of this species through hybridisation with feral dogs. Whatever the genetic intermixing, it is clear that for over 4000 years dingoes have played a functional role in the Australian landscape. Top predators are now understood to be ecologically important in maintaining diversity. The loss or suppression of top predators can lead to additional extinctions through the food chain, and an increase of cats and foxes that negatively impact native wildlife in Australia. A review of the literature on the role of the dingo in the Australian environment identified the following key points:
1. Dingoes kill and compete with cats and foxes, and alter the foraging behaviour of feral cats. This suppression of smaller predators can have net positive benefits for populations of threatened species.
2. Dingoes can control populations of herbivores. Kangaroo numbers increase with rainfall and, when present, dingoes limit their population through predation. This reduces grazing pressure on grasslands.
3. Lethal control of dingoes can disrupt the social structure of packs that would otherwise limit dispersal, hybridisation and attacks on stock.
4. Alternatives to lethal control and the dingo fence exist. For example, livestock guardian dogs can protect stock from dingo predation. This alternative is cost effective as it will provide a return on investment in 1 to 3 years.