Australasian Science: Australia's authority on science since 1938

Dingo Poisoning Harms Native Mammals

Poisoning of dingoes – the top predators in the Australian bush – has a deleterious effect on small native mammals such as marsupial mice, bandicoots and native rodents, according to research conducted in forested national parks in NSW.

The research, published in Proceedings of the Royal Society B, found that loss of dingoes after baiting is associated with greater activity by foxes, which prey on small marsupials and native rodents.

Furthermore, the number of kangaroos and wallabies increases when dingoes disappear. Grazing by these herbivores reduces the density of the understorey vegetation in which the small ground-dwelling mammals live.

A team led by Dr Mike Letnic of the University of NSW surveyed seven pairs of forested sites within conservation reserves managed by the NSW National Parks and Wildlife Service. Baiting of dingoes with 1080 poison had been carried out at one location in each pair of locations, which had similar eucalypt coverage, geology and landforms, and were less than 50 km apart.

“We found foxes and large herbivores benefit from dingo control, while small-bodied terrestrial mammal species decline in abundance,” Letnic said. “Predation by foxes is one of the most important threats to small native mammals, and grazing by herbivores can reduce their preferred habitats for shelter, leaving them exposed to predators.

“Actively maintaining dingo populations, or restoring them in areas where they have been exterminated, is controversial but could mitigate the impacts of foxes and herbivores,” Letnic said. “Poisoning of dingoes is counter-productive for biodiversity conservation because it results in increases in fox activity and declines of small ground-dwelling native mammals.”

The study’s findings in the forested areas are consistent with the effects of dingo removal in desert areas of Australia.