Foxes are an adaptable predator
Image: Daryl Panther
Foxes are an efficient and extremely adaptable predator listed as a national threat in the Commonwealth
Endangered Species Protection Act 1992
. Although primarily a carnivore (meat eater), foxes will also eat insects and fruit when other prey is scarce. A wide diet allows foxes to survive in a wide range of habitats, including urban, alpine and desert areas, and has been a very successful coloniser of the Australian continent.
How would foxes impact on Tasmania's wildlife?
Tasmania is home to unique native wildlife that has flourished in the protection offered by this island state's isolation. Tasmania is the final refuge for a long list of species that have all but disappeared from the mainland, including the eastern quoll, bettong, native hen and pademelon. Other species, such as the Eastern barred bandicoot, occur in high numbers in Tasmania but are on the verge of extinction on the mainland. The main cause of the decline or extinction of this wildlife on the mainland is fox predation. Many other wildlife species would also suffer from competition with foxes for resources.
In the past, devils have probably been playing a role as a 'buffer' species for any foxes that have entered the state, providing competition that may have prevented fox establishment. However, the population decline of the Tasmanian devil, as a result of the
Devil Facial Tumour Disease
, partly removes this barrier and makes the fox eradication effort all the more important.
If foxes fill the void created by lower devil numbers, it could prevent the Tasmanian devil from re-establishing, should the disease be eliminated.
Should foxes become established in Tasmania, over 70 native vertebrate species would be at risk. Of these, 34 species have locally restricted ranges, 16 are suspected to be already declining in distribution and 12 species are threatened according to Commonwealth or State threatened species legislation. It is quite possible that at least 5 wildlife species will be driven to extinction. Numerous invertebrate species are also at risk.
Locally widespread species like ducks, shorebirds, ground nesting birds, blue tongue lizards, mountain dragons, skinks, frogs, little penguin and platypus are also at risk and would decline in the Tasmanian landscape if foxes establish. The flow-on effects through food chains and ecosystem balance must also be considered an unknown factor.
How would foxes impact on Tasmania's agriculture?
Foxes have an enormous impact on Australian agriculture and the economy. Foxes are estimated to kill 5-10% of lambs Australia-wide but research has shown that kill rates may be as high as 30% in some regions. Foxes can also attack sub-adult and adult sheep and goats, and sometimes calves. Losses to Tasmania's lamb and wool industries from foxes would be in the vicinity of several million dollars per annum.
Horticultural enterprises, such as vineyards and orchards, may experience loss of fruit to foxes, either from fruit eaten directly or through damage to, for example, grape bunches which are then unsaleable. Foxes also have an unusual habit of chewing on irrigation emitters, such as plastic drippers, and can potentially destroy thousands of dollars of irrigation infrastructure.
How would foxes impact on domestic animals?
Foxes regularly prey upon domestic chickens, ducks, geese and turkeys, as well as goat kids. The young of all free-range poultry are easy targets for foxes.
Fox in a chicken pen
Image: Chris Lane, courtesy of Invasive Animals CRC
Surplus killings will sometimes occur in enclosed spaces such as chicken coops, with discarded feathers and headless bodies being an indicator of fox predation. Foxes are also noted for caching (burying) surplus food and carrying small carcasses (dead bodies of animals) back to their dens to feed their young.
What diseases could foxes spread?
Foxes carry many diseases that can infect both native wildlife and domestic animals, particularly dogs. These include hydatids, distemper, parvovirus, canine hepatitis, heartworm and sarcoptic mange.
What impact would foxes have on other Tasmanian industries?
Nature-based tourism is an important component of the Tasmanian economy as tour operators and visitors alike realise the unique natural resources that Tasmania has to offer. Visitation statistics show that 70% of tourists participate in a nature-based tourism activity whilst in Tasmania. The loss of our unique wildlife to foxes would impact on the marketability of this industry and result in job abd business losses.Fact sheets:
Enemy of the State - June 2012 (274 KB)
What's on the menu? - June 2012 (416 KB)