Feral donkeys were first brought to Australia as pack animals to replace horses, which had succumbed to native poisonous plants. Now numbering 5 million, they have been declared a pest, owing to their damage to vegetation and erosion of soil. Culling is mainly carried out by marksmen in helicopters, and experiments are being made in fertility control.
Feral donkeys in Australia (and elsewhere) are donkeys (scientific name Equus asinus) which escaped from captivity, and are living and breeding in the wild. Donkeys originated in Africa and in parts of Asia. They are a part of the family Equidae. While donkeys display many horse-like characteristics, they are more closely related to wild asses.
Donkeys were brought to Australia in 1866 for use as pack and haulage animals. [1] Up until that point, the Australians had been using the horse as their main mode of transportation. However, problems arose when the horses used in transportation began to become sickened by some of the native poisonous plants. When donkeys proved to be invulnerable to the plants that were making the horses sick, more donkeys were brought in. Escape was common because of the lack of fences, and there were reported herds of donkeys by the 1920s. In western Australia in 1949, there were enough donkeys for them to officially be declared a pest. [1] There were almost 5 million feral donkeys in Australia in 2005. [2]
Donkeys are herbivores, and only eat vegetation. All year round, the donkeys graze for grass, shrubs, and tree bark. Donkeys usually graze for 6 to 7 hours a day and can go a fair distance from water sources. [1] There are over 1 million donkeys living in Australia, which means that the donkeys eat a significant amount of vegetation. [1] The donkeys can readily find food in winter if it is wet; however food is much less plentiful in times of drought.
The ecological effects of feral donkeys in Australia are debated; Some researchers claim that the donkeys’ ecological niche, like that of other introduced large herbivores, may correspond to lost niches of extinct Australian megafauna and benefit the native ecosystem. [3]
There are some negative effects that feral donkeys may have on the environment: they may spread weeds by carrying seeds in their hair and faeces, they may damage vegetation through overeating, they may foul watering holes in the drought season, and they can cause erosion with their hard hooves. [1] These damages, particularly those to watering holes, may play a role in the extinction of native plants and animals. Feral donkeys also affect local agriculture, as they sometimes overeat pasture grasses and destroy fences. They are also known to infect domestic animals with diseases.
Since feral donkeys in Australia are considered a pest, they are often controlled by being mustered. Helicopters with highly trained and accredited shooters have replaced this technique in places where the terrain makes mustering too difficult. [4] Also seeing some limited use is fertility control. This, however, is difficult with large numbers of undomesticated animals and it is unknown whether this technique will make a difference on such a large number of animals. [1] Some good cattle breeders are using donkeys against dingos and foxes. There is some trafficking of donkey skin for making donkey-hide gelatin in traditional Chinese medicine. [5]
Overgrazing occurs when plants are exposed to intensive grazing for extended periods of time, or without sufficient recovery periods. It can be caused by either livestock in poorly managed agricultural applications, game reserves, or nature reserves. It can also be caused by immobile, travel restricted populations of native or non-native wild animals.
The donkey or ass is a domesticated equine. It derives from the African wild ass, Equus africanus, and may be classified either as a subspecies thereof, Equus africanus asinus, or as a separate species, Equus asinus. It was domesticated in Africa some 5000–7000 years ago, and has been used mainly as a working animal since that time.
The onager, also known as hemione or Asiatic wild ass, is a species of the family Equidae native to Asia. A member of the subgenus Asinus, the onager was described and given its binomial name by German zoologist Peter Simon Pallas in 1775. Six subspecies have been recognized, two of which are extinct.
A feral animal or plant is one that lives in the wild but is descended from domesticated individuals. As with an introduced species, the introduction of feral animals or plants to non-native regions may disrupt ecosystems and has, in some cases, contributed to extinction of indigenous species. The removal of feral species is a major focus of island restoration.
Equus is a genus of mammals in the family Equidae, which includes horses, asses, and zebras. Within the Equidae, Equus is the only recognized extant genus, comprising seven living species. Like Equidae more broadly, Equus has numerous extinct species known only from fossils. The genus originated in North America and dispersed into the Old World and South America during the Early and Middle Pleistocene. Equines are odd-toed ungulates with slender legs, long heads, relatively long necks, manes, and long tails. All species are herbivorous, and mostly grazers, with simpler digestive systems than ruminants but able to subsist on lower-quality vegetation.
Invasive species in Australia are a serious threat to the native biodiversity, and an ongoing cost to Australian agriculture. Numerous species arrived with European maritime exploration and colonisation of Australia and steadily since then. There is much ongoing debate about the potential benefits and detriments of introduced species; some experts believe that certain species, particularly megafauna such as deer, equids, bovids, and camels, may be more beneficial to Australia's ecosystems than they are detrimental, acting as replacements for extinct Australian megafauna.
A brumby is a free-roaming feral horse in Australia. Although found in many areas around the country, the best-known brumbies are found in the Australian Alps region. Today, most of them are found in the Northern Territory, with the second largest population in Queensland. A group of brumbies is known as a "mob" or "band".
Australian feral camels are introduced populations of dromedary, or one-humped, camel. Imported as valuable beasts of burden from British India and Afghanistan during the 19th century, many were casually released into the wild after motorised transport negated the use of camels in the early 20th century. This resulted in a fast-growing feral population with numerous ecological, agricultural, and social impacts.
The African wild ass or African wild donkey is a wild member of the horse family, Equidae. This species is thought to be the ancestor of the domestic donkey, which is sometimes placed within the same species. They live in the deserts and other arid areas of the Horn of Africa, in Eritrea, Ethiopia and Somalia. It formerly had a wider range north and west into Sudan, Egypt, and Libya. It is Critically Endangered, with about 570 existing in the wild.
A feral horse is a free-roaming horse of domesticated stock. As such, a feral horse is not a wild animal in the sense of an animal without domesticated ancestors. However, some populations of feral horses are managed as wildlife, and these horses often are popularly called "wild" horses. Feral horses are descended from domestic horses that strayed, escaped, or were deliberately released into the wild and remained to survive and reproduce there. Away from humans, over time, these animals' patterns of behavior revert to behavior more closely resembling that of wild horses. Some horses that live in a feral state but may be occasionally handled or managed by humans, particularly if privately owned, are referred to as "semi-feral".
Asinus is a subgenus of Equus that encompasses several subspecies of the Equidae commonly known as wild asses, characterized by long ears, a lean, straight-backed build, lack of a true withers, a coarse mane and tail, and a reputation for considerable toughness and endurance.
The Banker horse is a breed of semi-feral or feral horse living on barrier islands in North Carolina's Outer Banks. It is small, hardy, and has a docile temperament, and is genetically related to the Carolina Marsh Tacky of South Carolina and Florida Cracker Horse breeds through their shared Colonial Spanish horse and Iberian horse descent. The current population of wild Banker horses is estimated to be about 400.
Conservation grazing or targeted grazing is the use of semi-feral or domesticated grazing livestock to maintain and increase the biodiversity of natural or semi-natural grasslands, heathlands, wood pasture, wetlands and many other habitats. Conservation grazing is generally less intensive than practices such as prescribed burning, but still needs to be managed to ensure that overgrazing does not occur. The practice has proven to be beneficial in moderation in restoring and maintaining grassland and heathland ecosystems. Conservation or monitored grazing has been implemented into regenerative agriculture programs to restore soil and overall ecosystem health of current working landscapes. The optimal level of grazing and grazing animal will depend on the goal of conservation. Different levels of grazing, alongside other conservation practices, can be used to induce desired results.
The feral goat is the domestic goat when it has become established in the wild. Feral goats occur in many parts of the world.
Grazing pressure is defined as the number of grazing animals of a specified class per unit weight of herbage. It is well established in general usage.
The Barmah National Park, formerly Barmah State Park, is a national park located in the Hume region of the Australian state of Victoria. The park is located adjacent to the Murray River near the town of Barmah, approximately 225 kilometres (140 mi) north of Melbourne. The park consists of river red gum floodplain forest, interspersed with treeless freshwater marshes. The area is subject to seasonal flooding from natural and irrigation water flows.
Feral goats are an invasive animal species in Australia. First arriving in the 18th century with European settlers, feral goat populations originated from escaped domestic individuals. Today, feral goats are found across Australia, where they cause economic and environmental damage through overgrazing and competition with livestock and native marsupials.
The Pryor Mountains Wild Horse Range is a refuge for a historically significant herd of free-roaming mustangs, the Pryor Mountain mustang, feral horses colloquially called "wild horses", located in the Pryor Mountains of Montana and Wyoming in the United States. The range has an area of 39,650 acres (160.5 km2) and was established in 1968 along the Montana–Wyoming border as the first protected refuge dedicated exclusively for mustangs. It was the second feral horse refuge in the United States. About a quarter of the refuge lies within the Bighorn Canyon National Recreation Area. A group of federal agencies, led by the Bureau of Land Management, administers the range.
Brumby shooting or brumbies shooting is the practice of eradicating feral horses, or "brumbies", in Australia. It has been conducted since the 1800s, and continues into the present day. The term "brumby" was first recorded in the 1870s. Reasons for brumby shooting include, but are not limited to: demands for grazing land and water for domestic herds, sport, to maintain pastoral stations, to reduce environmental damage caused by the horses, to control disease, and to prevent possible road collisions.
In biology, overabundant species refers to an excessive number of individuals and occurs when the normal population density has been exceeded. Increase in animal populations is influenced by a variety of factors, some of which include habitat destruction or augmentation by human activity, the introduction of invasive species and the reintroduction of threatened species to protected reserves.