|Common name:||red fox|
|Other common name/s:||European red fox, fox|
This species is an established pest animal in the state of Victoria.
History of spread
European settlers introduced the red fox into Australia for sporting purposes in the 1850s, with most releases being around Melbourne. Foxes became established following two subsequent releases in 1871 at Ballarat and Geelong, Victoria. Following this and other introductions to Victoria, foxes were reported in NSW by 1893, in South Australia by 1901, in Queensland by 1907 and in Western Australia by 1912. By 1917 foxes were found 500 km west of Kalgoorlie.
Within 20 years of their introduction, foxes had been declared as a pest species in Victoria. Within 100 years foxes had reached their current distribution on mainland Australia. Today foxes range over 75 per cent of the continent. It has been suggested that the spread of foxes was strongly linked to the spread of rabbits and that the establishment of both species was helped along by deliberate releases as European settlement expanded.
Distribution in Victoria
The present distribution of the red fox covers all of mainland Australia, except for the tropical north. Tasmania was once free of foxes but this has changed with a recent illegal introduction and an eradication campaign is now underway.
Foxes are members of the Canidae family and are related to dogs, jackals, coyotes and wolves. There are 21 different species of fox throughout the world, although only the red fox is found in Australia.
The red fox has big ears, a bushy tail and variable coat colour and pattern. Reddish-brown above, foxes have a whitish chin, throat, chest and belly. Foxes have a distinctive tip on their tail, usually white but often be black or dark red. Foxes have a narrow chest, long legs and have long, high-set, moveable claws which remain sharp and make foxes excellent climbers and burrowers.
Whilst fox size varies, males typically weigh 4 to 8 kilograms and females 4 to 6 kilograms. Foxes are sometimes referred to as the cat-like canid.
Foxes are chiefly nocturnal (night time) hunters, being most active in the evenings and early mornings (crepuscular). Fox family groups usually occupy well-defined home ranges. Foxes use scent markings with urine, scats (droppings) and secretions from anal glands, plus aggressive and non-aggressive confrontations and vocalisations to define the home ranges.
Foxes communicate by sound and have a broad repertoire of around 28 groups of vocalisations. Calls are made in greeting, excitement, as a threat, in defence, while fighting, as an acknowledgment of inferiority or submission, as a warning or alarm, in social contact and in defence of territories. Infantile calls are basically calls for attention.
The red fox is solitary by nature. There is little cooperation in the defence of the territory or hunting due to the small prey size of foxes. However foxes have been observed working in groups to take advantage of calving cows having difficulties with births. Additionally, foxes will travel beyond their home ranges to congregate where there is a seasonal abundance of food offered by lambing flocks or fledglings from migratory birds.
Foxes may travel up to 10-15 km per night within their home range, revisiting sites of interest several times a night. By day, foxes usually rest in hides which may be a hollow log or tree, an enlarged rabbit burrow or dense undergrowth. A fox may use several resting sites within its home range and does not necessarily return to the same site each day.
Red fox social behaviour is limited to the rearing of cubs with a strong social structure during the breeding season. These social groups consist of a dominant adult male (dog) and a dominant adult female (vixen), together with several subordinate vixens which are usually related. Usually, only the dominant female produces a litter of cubs and the subordinate females help rear the cubs of the breeding vixen.
Red foxes cache (bury) surplus food for future consumption, which is a basic survival strategy. Caching is usually no more than simply placing the food in a small hole or depression and then lightly covering it with soil or debris. Food is normally eaten immediately until appetite is satisfied but when their hunger is appeased, the fox continues to hunt, scavenge and cache.
During lean times when bad weather or injuries result in poor hunting success, the fox relies on these caches for survival. Adult foxes and cubs will defend cached food and will move food to another location if disturbed by other foxes. Foxes will tend to eat the most preferred items and cache the least preferred items. To reduce the risk of other foxes or scavengers finding cached food, foxes spread the food items, rather than clump items together at a single cached site.
Foxes exhibit surplus killing behaviour defined as, killing prey at a rate beyond the immediate requirements of the predator. Surplus killing appears to reflect ineffective anti-predator defences by prey species when encountering a new and efficient predator .
Red foxes have long, sharp teeth, very quick reflexes and kill by multiple bites around the head and neck. Typically foxes inflict several deep facial bites and deep punctures around the neck. Birds such as poultry may only have the head and neck eaten, large feathers are chewed off rather than plucked out. Relatively large prey such as lambs typically have their tail, ears and tongues eaten and often the chest cavity is opened to eat internal organs. If the skin around the neck is cut back many small holes may be evident as a result of fox kill. Lambs and calves sometimes have their tongues eaten by foxes and sheep or cows can have teats or vulvas chewed off.
Foxes are highly adaptable, opportunistic omnivores eating meat, insects and plant materials. Foxes hunt and scavenge, mostly eating meat and taking a wide variety of vertebrate or invertebrate prey, plant material and human refuse.
Where present, rabbits make up a large part of fox diet. Other common food items include; carrion (domestic livestock and native fauna), house mice, insects, reptiles and amphibians, birds, grain, vegetable matter (including crops), and fruit crops such as grapes, apples and blackberries.
Invertebrates, sheep and rabbits are three of the most important staple food items for foxes that mostly inhabit agricultural landscapes where native prey species are less abundant.
Primary predation by foxes on domestic livestock is common and includes predation of poultry, new born lambs, goat kids, deer fawns, domestic emu and ostrich chicks, including isolated instances of calves from difficult birthing.
A large portion of the fox's diet can consist of introduced and native animals. Foxes mostly prey upon animals that weigh between 35-5,500 grams (sometimes referred to as critical-weight-range species) and ground-nesting birds; many of which are endangered or vulnerable.
In Victoria, prey, particularly rabbits, is abundant for most of the year and insects, mice and wild fruits are seasonally plentiful. Even when rabbits are low in numbers, there is usually a good supply of carrion, small rodents, reptiles, amphibians, insects and fruits for foxes to feed on.
Fox populations are widely established in urban, suburban, agricultural and natural environments throughout Victoria. Foxes inhabit many urban areas, especially where there is cover provided by parklands and reserves and food is easy to find. They can also be found in the suburbs of most large cities in Australia. The densities of foxes residing in cities (3-16 per sq km) can be considerably higher than densities observed in farmland in central Victoria (4 per sq km).
Red foxes have few natural predators in Australia, with most mortality occurring because of human intervention or drought. Fox cubs are vulnerable to birds of prey and dogs.There is some evidence that local populationscan be suppressed by predation from dingoes.
Diseases and parasites
Foxes are susceptible to the same diseases as dogs which are transmissible between these animals. Mange and distemper are thought to be important causes of mortality in wild fox populations, however little is known about their role in regulating Australian fox populations.
The fox is a carrier of rabies (where present) and could be a major vector for the spread of the disease if introduced to Australia.
Foxes exibit both monogamy and polygamy. Monogamy is when one male and one female form a breeding pair. Monogamy may be limited to one breeding season or it may extend for a lifetime. Polygamy is when the male mates with several females. The red fox is not completely monogamous as polygamy occurs through males roaming in search of receptive females, males mating with more than one female in the same range, and males monopolising the ranges of two vixens.
Vixens mate once a year and will accept males over a three-day period and are stimulated to breed by changing day length and food availability. Male foxes are infertile from September to March due to the absence of sperm in the testes during this period. Within Australian fox populations, mating occurs over a 3 to 7 week period from mid-June to the end of July.
Fox litter size varies from 3 to 5 cubs per vixen with 85-97 per cent of vixens pregnant each season. Pregnancy lasts for 51-53 days and cubs are born early August to late September.
Young foxes disperse from their family unit at the end of summer and beginning of autumn which results in a large floating population of young foxes looking for a more permanent place to live. Since the mortality of adult foxes is considerably high (50-60 per cent), there is a rapid and considerable change in territory occupancy from one year to another.
Males are more likely to leave the parent's territory than females and to travel greater distances; with males moving on average about 68km, and females about 14km. It is believed that the dog fox acts more aggressively towards his male offspring, eventually chasing them off his territory. In many instances the young female foxes do not move very far into new territory and some even remain in the parent's territory helping them to raise the next litter.
Red fox cubs are generally born in dens during August to September but litters have been found in hollow trees, rock crevices and under houses.
The vixen remains in the birth den for the first two weeks to feed, protect and provide warmth for the cubs.
The cub's eyes begin to open after 8 to 14 days.
Regurgitated meat is consumed at around three weeks and partly digested whole food items are consumed around four weeks of age. Vixens cease lactating and wean cubs at five to eight weeks.
Cubs emerge from the den at around six weeks of age and by 8-10 weeks the cubs abandon the den and live on the surface.
At three months of age they hunt for small animals and gradually gain independence by January-February.
Although they may stay in family groups, juvenile foxes become completely independent by March.
Dispersal from the natal area can occur from March onwards when juvenile foxes are 6-9 months old.
Young foxes are sexually mature by 9-10 months with 85 per cent of young females breeding in the first year.
Foxes are short lived in the wild with about 60 per cent mortality occuring in the first year of life. Most surviving foxes live to around two years of age with only approximately three per cent of foxes living to five years.
Impact on ecosystems and waterways
In Australia, foxes could be classified as a keystone species that reduces biodiversity and impacts on the survival of native prey over large areas of entire ecosystems. The impact of the red fox combined with habitat degradation is the most likely cause of 'at risk' native animal declines. The environmental costs associated with foxes ($190 million) are considerably greater than their agricultural impact ($17.5 million) and consequently, any large-scale reduction in fox densities could generate significant environmental benefits.
Fox predation has been listed as a key threatening process under schedule 3 of the Commonwealth Endangered Species Protection Act 1992 and the Environment Protection and Biodiversity Conservation Act 1999. A key threatening process is that which threatens, or may threaten, the survival, abundance or evolutionary development of a native species or ecological communities.
Foxes are considered a threat to 14 species of birds, 48 mammals, 12 reptiles and two amphibians, with the orange-bellied parrot, spotted quail-thrush (from Mt Lofty Ranges), herald petrel, Gilbert's potoroo and western swamp tortoise listed as critically endangered.
Foxes are thought to have played a major part in the demise and extinction of many ground-dwelling native species in the last 130 years. It has been suggest that surplus killing by foxes may have been a major contributor to the rapid mainland extinction or reduction of a range of native species in Australia.
Almost any animal up to 5.5 kilograms in weight is at risk from foxes. A single fox is estimated to eat about 400 grams of food each night. Over a year, this equates to around 150 kilograms of food. However, as foxes may kill many animals in a night, yet only consume a small amount of each, this will amount to thousands of mammals, reptiles, birds and insects killed each year by a single fox.
Among many other items, the scats of foxes contain the remnants of fruit and berries from native and introduced species. Introduced plant species found in fox scats include Boxthorn (Lycium ferocissimum), Sweet Briar (Rubus rubiginosa), Blackberry (Rubus frutiscosis). Foxes are presumed to be legitimate dispersers of seeds for they consume and defecate viable seeds. A seed takes 4 to 48 hours to pass through a fox's digestive system, allowing time for seeds to be distributed over wide distances. It is also likely that seeds are dispersed attached to fox fur.
Agricultural and economic impacts
The economic impact of foxes in Australia has been estimated at around $227.5 million per annum. This includes $17.5 million in sheep production losses, $190 million in environmental impacts, $16 million in management costs and $4 million in research costs. Agricultural impact was estimated by assuming a 2 per cent predation loss from the value of 35 million lambs marked per year at a cost of $25 per head. In 2009, lost production due to lamb predation alone was estimated at approximately $2 million dollars for Victoria and Tasmania. These production losses are rather conservative in today's environment where lamb retail prices are higher.
Primary fox predation may result in 4-30 per cent of lamb loss but their impact on agricultural production remains unquantified. In south-eastern Australia it is estimated that a 0.8-5.3 per cent lamb loss is due to fox predation. In the more arid areas of western NSW, up to 30 per cent of lambs are taken by foxes.
Total economic impact must also take into account the loss of potential genetic gain, the redirection of resources away from farm activities to control effort and reduced land values.
If rabies were to become established on the Australian continent the impacts would be devastating for native animals and domestic livestock. Rabies mostly affects members of the dog family, but can also be passed on to humans, livestock and native animals.
Impact on social value and health
Foxes cause significant distress and hardship when they kill livestock such as poultry and lambs. Foxes carry diseases that are transmissible to domestic dogs and humans such as sarcoptic mange, hydatids and leptospirosis.
Urban foxes are a nuisance pest with behaviour including harassing domestic animals, eating pet food, raiding rubbish bins, defecating or digging in gardens, and chewing infrastructure such as garden hoses and irrigation systems.
Foxes may also prey upon native and domesticated animals including unprotected poultry, rabbits, guinea pigs and aviary birds and can spread parasites and diseases such as mange and distemper to domestic animals and pets.
Recommended control measures
The Department of Economic Development, Jobs, Transport and Resources (DEDJTR) recommends integrated pest management using all available control measures implemented in a coordinated manner at a landscape scale.
Read more about fox management
- Cavallini, P. 1996. Variation in the social system of the red fox. Ethology, Ecology and Evolution 8, 323-342.
- Coman, B.J 1973, The Diet of Red Foxes (Vulpes vulpes) in Victoria, viewed 9th November 2009 at URL: http://www.publish.csiro.au/paper/ZO9730391.htm
- Bustamante, R.O., Simonetti, J.A. and Mella, J.E. (1992) Are foxes legitimate and efficient seed dispersers – a field test. ACTA Oecologica – International Journal of Ecology, 13: (2) 203-208
- DEWHA. 2008a. Background document for the threat abatement plan for predation by the European red fox. Department of the Environment, Water, Heritage and the Arts (DEWHA), Canberra.
- DEWHA 2008b. Threat abatement plan for predation by the European red fox, Department of the Environment, Water, Heritage and the Arts (DEWHA), Canberra.
- European red fox PestSmart Fact Sheet accessed on 10th February 2012 http://www.feral.org.au/pestsmart-factsheet-fox
- Gong W., Sinden J., Braysher M. and Jones R. 2009 The economic impacts of vertebrate pests in Australia. Invasive Animals Cooperative Research Centre
- Graae, B.J., Pagh, S. and Bruun, H.H. (2004) An experimental evaluation of the Arctic fox (Alopex Lagopus) as a seed disperser. Arctic, Antarctic and Alpine Research, 36: (4) 468-473)
- Greentree, C., Saunders, G., McLeod, L. and Hone, L. (2000). Lamb predation and fox control in southeastern Australia. Journal of Applied Ecology 37, 935-943
- Henry, D.J. 1996. Red Fox; The Catlike Canine. Smithsonian Institute Press, Washinton,D.C., London
- Kinnear, J R, Sumner N.R., Onus, M.L., The red fox in Australia—an exotic predator turned biocontrol agent, Biological Conservation 108 (2002) 335–359
- Lloyd, H.G. (1980). Habitat requirements of the Red Fox. In The Red Fox, ed E.Zimen. Biogeographica, Vol 18, p 7. Dr W. Junk B.V. publishers, the Hague-Boston-London.
- Lugton, I.W. (1993) Fox predation on lambs. In 'Australian Sheep veterinary Society ' Australian Veterinary Association, Gold coast, pp 17-26
- Macdonald, D. W. (1976). Food caching by red foxes and some other carnivores. Zeitschrift fur Tierpsychologie 42, 170-185.
- Macdonald, D.W. (1979) 'Helpers' in fox society. Nature 282: 69–71. In managing vertebrate pests foxes
- McIlroy, J.C., Saunders, G.R., and Hinds, L. 2001. The reproductive performance of female red foxes, Vulpes vulpes, in central-western New South Wales during and after a drought. Canadian Journal of Zoology 79, 545-553
- McIntosh, D.L. (1963a) Reproduction and growth of the fox in the Canberra district.CSIRO Wildlife Research 8: 132–141.
- McLeod, R. (2004) Counting the Cost: Impact of Invasive Animals in Australia 2004. Cooperative Research Centre for Pest Animal Control. Canberra
- Reynolds, J. C. 2000 Fox Control in the Countryside. The Game Conservancy Trust,
- Rolls, E. (1969). They All Ran Wild. The Story of Pests on the Land in Australia. Angus & Robertson : Sydney.
- Saunders, G., Coman, B., Kinnear, J. and Braysher, M. 1995. Managing Vertebrate Pests: Foxes. Bureau of Resource Sciences, Australian Government Publishing Service, Canberra.
- Saunders, G., Kay, B. and McLeod, L. 1999. Caching of baits by foxes (Vulpes vulpes) on agricultural lands. Wildlife Research 26(3): 335-340.
- Short, J., Kinnear, J. E. And Robley, A. (2002). Surplus killing by introduced predators in Australia—evidence for ineffective anti-predator adaptations in native prey species? Biological Conservation 103 283-301
- Tembrock, G. (1963). Acoustic behaviour of mammals, In R.G. Busnel, ed., Acoustic behaviour of mammals. Amsterdam: Elsevier