The solution to the global explosion in feral animal populations such as foxes, coyotes and even cats could lie in the reintroduction of apex predators like dingoes, supported by nature corridors, research shows.
Dingoes and other top predators need large ranges to be able to control smaller predators whose populations have expanded to the detriment of a balanced ecosystem.
That's the main finding of a study led by the University of Sydney that analysed the relationship between top predators on three different continents and the next-in-line predators.
The findings were published in Nature Communications and were similar across continents, showing that as top predators' ranges were cut back and fragmented, they were no longer able to control smaller predators.
Lead researcher Dr Thomas Newsome, from the University of Sydney’s School of Life and Environmental Sciences and Deakin University’s Centre for Integrative Ecology, said the new research showed fox numbers were reduced where dingoes were high in abundance, compared to areas where foxes existed alongside fewer dingoes.
“Humans need a greater tolerance of apex predators if we want to enjoy the environmental benefits they can provide”
“We know that apex predators can have benefits to ecosystems, but human modifications, like the widespread clearance of land for livestock grazing and cropping, are making that hard,” Dr Newsome said.
“Foxes and cats are killing many threatened small-medium sized mammal species – including bilbies and wallabies – and they also spread diseases and impact on agriculture.”
“Dingoes don’t pose the same risk to these threatened species, as the smaller mammals have been able to develop effective anti-predator strategies to coexist with dingoes since they were introduced around 4,500 years ago.
“Unfortunately, our native mammals have not developed sufficient anti-predator strategies to coexist with foxes and cats – essentially making them sitting ducks.”
“Humans need a greater tolerance of apex predators if we want to enjoy the environmental benefits they can provide”, said Dr Newsome.
Organisations involved in the research paper include Oregon State University, the University of Washington, the University of Belgrade, the University of Tasmania, the University of Ljubljana, the University of New South Wales, the University of Forestry, Sofia, the University of Sydney and Deakin University.