Below is some information that details the damage that these introduced species and ferals do. Fox Info
The European fox, was introduced into Australia in the early 1870s for recreational hunting purposes. The spread of the fox closely followed the distribution of rabbits across mainland Australia. Today, foxes are found in most areas of the mainland south of the tropics and, unfortunately, are e
ven believed to have been deliberately released in Tasmania. Foxes cause environmental damage, by preying on many species of Australian native wildlife. Foxes include birds, small mammals and reptiles in their menu. The extinction or endangerment of native wildlife is a national disaster. Foxes significantly contribute, alongside other vertebrate pest species and the impact of man, to the extinction pressures. Effective fox control has been shown to reduce the extinction pressure and to allow population recovery. Serious economic damage results from fox predation on farm livestock , including lambs, calves, poultry, water fowl and goats. With a typical fox density about 4 foxes per 400 hectare (1000 acres), each fox will eat about 400 grams a night, or a little over a tenth of a tonne of food in a year. Overall, about a third of this diet is from farm livestock, a third from pest vertebrates like rabbits and mice, and a third from wildlife. However, foxes are opportunistic and if lambs are available they will make up 100% of the diet. Predation on other pest vertebrates does not provide effective control for these pests, because, unlike native animals, rabbits and mice can breed faster than the foxes can eat them. In uncontrolled areas, foxes have been shown to cause lamb losses of 10% to 30%. Under extreme conditions, predation on lambs can be as high as 50%. Fox predation has also been reported on calves, cows in birth difficulty, deer, ostrich and emu chicks, and free-range poultry. The national cost of direct fox predation of lambs is estimated at more than A$100 million annually. If lamb marking in a 500ha farm increases from a typical figure of 80% to nearly 100% (i.e. 100 lambs marked per 100 ewes mated), as has been shown in the field, then the gross return to the farmer could be 20 to 50 times the investment in a fox control programme. Rabbit Info
Rabbits, like most other pest species, were introduced when Europeans first settled in Australia. The rapid spread of the rabbit led to the destruction of large tracts of vegetation, leading to the extinction of many plant species. Loss of vegetation leads to soil erosion as the exposed soil is washed or blown away, removing valuable soil nutrients required for new plants to develop. This soil is typically deposited in waterways, causing siltation and destroying aquatic ecosystems. This wanton destruction of habitat has contributed to the demise of many native marsupial species such as the bilby and the bandicoot as their feed sources were outstripped by marauding rabbits. Rabbits actively compete with domestic livestock and can alter pasture composition by selectively grazing on more palatable and nutritious plants. Seven to ten rabbits eat the equivalent of one adult sheep, and, during drought periods, rabbits can totally strip a landscape bare leaving no food for sheep, cattle or native animals. Feral Dogs
Wild dogs have been a problem in Australia since the middle of the 19th century and have been trapped, shot and baited to reduce their impact on farm livestock since then. Wild dogs include dingoes and hybrid animals that prey on livestock in agricultural and pastoral areas. Wild dog predation on sheep has long been recognised, but there is also evidence that dogs, hunting in packs, can bring down calves and even full-grown cows. Wild dogs hunt in packs and cause significant losses to small and large native wild-life. Wild dog predation on livestock and native wildlife is a considerable national problem. Agricultural producers in Queensland claim that thousands of sheep have been taken by increasing numbers of wild dog attacks, driving some producers out of the industry. Wild dogs also impact on native environments by:
•hunting native animals;
•breeding with purebred dingoes, causing the hybridisation of this "native" species;
•carrying diseases and parasites; and
•competing with native carnivores, such as quolls. Feral Pigs
Pigs were introduced into Australia with the arrival of European settlers. As settlers moved around the country, pigs were common domesticated companions. When these animals escaped from captivity they quickly established wild populations. There are now estimated to be over 23 million feral pigs in Australia, concentrated predominantly in NSW, Queensland and across the top of the Northern Territory. In other areas of the country, small isolated populations are present. The distribution and abundance of feral pigs fluctuates markedly between years based on environmental conditions and availability of food and water. The agricultural impact of feral pigs alone has been estimated to be more than $100 million annually. Impacts include lamb predation, infrastructure damage, crop and pasture damage, water fouling, disease spread, erosion, competition with stock and the huge costs of control. Lamb and goat predation is so serious that vast areas infested with pigs have become unusable for sheep farming. Lamb losses of around 15% to pigs is common but losses as high as 38% have been reported. Feral pigs are known to be vectors for a number of serious endemic and exotic diseases that have the potential to devastate commercial pig operations as well as transmitting to other animals and humans. Examples include Foot and Mouth Disease Virus (FMD), leptospirosis, brucellosis, melloidosis and Japanese encephalitis. The threat of an exotic disease outbreak such as Foot and Mouth Disease has led to an increased effort to control feral pigs. Should such a disease enter the feral pig population, it would prove difficult and extremely expensive to eliminate. The disease risk posed by feral pigs is regarded by some as a "ticking time bomb" for Australia if a serious exotic disease gains access to the wide-ranging pig population. Rooting and digging behaviour of feral pigs effectively ploughs up riparian vegetation and destroys native ecosystems, leaving these areas susceptible to soil loss, w**d establishment and to the spread of disease such as dieback (Phytophthora cinnamomi) through native vegetation. Feral pigs are opportunistic scavengers and prey on invertebrates, bird eggs, small mammals, reptiles, amphibians and soil invertebrates. Their selective feeding habits also affect the biodiversity of vegetation and creates competition for food resources of native species. Feral pigs have negative impacts on native ecological systems including changing species composition, disrupting species succession and by altering nutrient and water cycles. Impacts can be direct or indirect, acute or chronic, periodic or constant, and may be influenced by changing seasonal conditions. Feral pigs tend to congregate around water as they are highly susceptible to heat. The impact of the pigs wallowing in wetlands and watercourses totally destroys these finely balanced ecosystems. They also prey on ground dwelling mammals, reptiles and birds, in some cases putting extensive pressure on rare and endangered species. Hares
The European hare was introduced to Australia in the late 1830s in Tasmania, although this initial attempt to establish wild populations failed. The first successful colony of hares to establish in Australia was on the shores of Westernport Bay in 1862. The following year another hare colony was established on Phillip Island by the Acclimatisation Society of Victoria for the use in the sport 'coursing'. Hares released on the mainland thrived with limited hunting pressure. The hare became a widespread species throughout much of south-east Australia by 1870. Spreading at an approximate rate of 60 kilometres per year, hares crossed the Murray River in 1875, where they made their way along the western slopes and tablelands of New South Wales. By 1900, hares had reached the Queensland border and become a major agricultural problem in northern and western Victoria. European hares can cause significant damage when gnawing the bark of young trees and shrubs. European hares also chew off the stems of young trees, damaging or killing the plant. Hares can cause severe damage to revegetation sites. The European hare is an opportunistic feeder and as well as grazing predominately on grasses, it will also consume crops, such as vegetables, lucerne and cereal crops. This can cause significant economic loss to land owners that have European hares on or adjacent to their land. Hares can travel significant distances, so the potential for one animal to cause widespread damage to plants is relatively high. European hares can also be a problem in forestry, ornamental or fruit producing plantations as they can gnaw back the bark of young trees and vines. Feral Cats
Feral cats threaten the survival of over 100 native species in Australia. They have caused the extinction of some ground-dwelling birds and small to medium-sized mammals. They are a major cause of decline for many land-based endangered animals such as the bilby, bandicoot, bettong and numbat. Feral cats can carry infectious diseases which can be transmitted to native animals, domestic livestock and humans. Many native animals are struggling to survive so reducing the number killed by this introduced predator will allow their populations to grow. Feral cats—defined as those cats that live and reproduce in the wild and survive by hunting or scavenging—are found all over Australia in all habitats, including forests, woodlands, grasslands, wetlands and arid areas.
