Feral
Encyclopedia
A feral organism is one that has changed from being domesticated
to being wild
or untamed. In the case of plants it is a movement from cultivated to uncultivated or controlled to volunteer. The introduction of feral animals or plants to their non-native regions, like any introduced species
, may disrupt ecosystem
s and has, in some cases, contributed to extinction
of indigenous species. However, returning lost species to their environment can have the opposite effect, bringing damaged ecosystems back into balance.
By the same token, feral species may eliminate other "problem" species such as rodents, harmful insects, or aggressive plants.
states that a feral
animal is an animal which has escaped from a domestic or captive status and is living more or less as a wild animal. Other definitions realize the shortcomings of the first definition and simply say that a feral animal is an animal which has changed from being domesticated to being wild, natural, or untamed.
Zoologists generally exclude from the ‘feral’ category animals which were genuinely wild before they escaped from captivity: neither lion
s escaped from a zoo nor the sea eagle
s (Haliaeetus albicilla) recently re-introduced into the UK are regarded as 'feral'. As far as animals are concerned, this article assumes the ‘zoological definition’ of feral. Some common examples of animals with feral populations are horses, dogs, goat
s, cats, and pigs.
The term 'feral' should not be used to describe the naturalization of a wild (i.e. non-domesticated) species. Nor should "feral" be used to describe a population of a species which although descended from a domesticated population has severed itself from dependence on humans and lived independently in the wild for a long period.
. Persistence depends on their ability to establish themselves and reproduce reliably in the new environment
.
with its feral potential.
returns readily to a feral state if it has not been socialized properly in its young life. (See Feral cat
s.) These cats, especially if left to proliferate, are frequently considered to be pests in both rural and urban areas, and may be blamed for devastating the bird
, reptile
and mammal
populations. A local population of feral cats living in an urban area and using a common food source is sometimes called a feral cat colony. As feral cats multiply quickly, it is difficult to control their populations. Animal shelters attempt to adopt out feral cats, especially kittens, but often are overwhelmed with sheer numbers and euthanasia
is used. In rural areas, excessive numbers of feral cats are often shot. More recently, the "Trap-Neuter-Return
" method has been used in many locations as an alternate means of managing the feral cat population.
The goat
is one of the oldest domesticated creatures, yet readily goes feral and does quite well on its own.
The dromedary
camel, which has been domesticated for well over 3,000 years, will also readily go feral. A substantial population
of feral dromedaries, descended from pack animals that escaped in the 19th and early 20th centuries, thrives in the Australia
n interior today.
Sheep are close contemporaries and cohorts of goats in the history of domestication, but the domestic sheep is quite vulnerable to predation
and injury, and thus rarely if ever is seen in a feral state. However, in places where there are few predators, they get on well, for example in the case of the Soay sheep
.
Water buffalo
run rampant in Western and Northern Australia. This is the only part of the world where they are legally hunted in their original range. The Australian government encourages the hunting of feral water buffalo because of their large numbers.
Cattle
have been domesticated since the neolithic
era, but can do well enough on open range for months or even years with little or no supervision. Their ancestors, the Aurochs
, were quite fierce, on par with the modern Cape Buffalo. Modern cattle, especially those raised on open range, are generally more docile, but when threatened can display aggression. Cattle, particularly those raised for beef
, are often allowed to roam quite freely and have established long term independence in Australia
, New Zealand
and several Pacific Islands along with small populations of semi-feral animals roaming the southwestern United States and northern Mexico
. Such cattle are variously called Mavericks
, Scrubbers or Cleanskins. Most free roaming cattle, however untamed, are generally too valuable not to be eventually rounded up and recovered in closely settled regions.
Horse
s and donkey
s, domesticated about 5000 BCE, are feral in open grasslands worldwide (see feral horse
). In Portugal
, feral horses are called Sorraia
; in Australia
, they are called Brumbies
; in the American
west, they are called Mustangs
. Other isolated feral populations exist, including the Chincoteague Pony
and the Banker Horse
. They are often referred to as "wild horse
s," but this is a misnomer. There are truly "wild" horses that have never been tamed, most notably Przewalski's Horse
. While the horse was originally indigenous to North America, the wild ancestor died out at the end of the last Ice Age
. In both Australia and the Americas, modern "wild" horses descended from domesticated horses brought by European explorers and settlers that escaped, spread, and thrived.
The pig
(hog) has established feral populations worldwide, most notably in Australia, New Zealand, the United States, New Guinea
and the Pacific Islands. Pigs were introduced to the Melanesian and Polynesian regions by humans from several thousand to five hundred years ago, and to Australia and the Americas within the past 500 years. While pigs were doubtlessly brought to New Zealand by the original Polynesian settlers, this population had become extinct by the time of European colonization, and all feral pigs in New Zealand today are descendants of European stock. Many European wild boar populations are also partially descended from escaped domestic pigs and are thus technically feral animals within the native range of the ancestral species.
Rock Pigeon
s were formerly kept for their meat
or more commonly as racing animals and have established feral populations
in cities worldwide.
Colonies of honey bees often escape into the wild from managed apiaries
when they swarm; their behavior, however, is no different from their behavior "in captivity", until and unless they breed with other feral honey bees of a different genetic stock, which may lead them to become more docile or more aggressive (see Africanized bee
s).
Large colonies of feral parrots
are present in various parts of the world, with Rose-ringed Parakeet
s, Monk Parakeet
s and Red-masked Parakeet
s (the latter of which became the subject of the documentary film, The Wild Parrots of Telegraph Hill
) being particularly successful outside of their native habitats and adapting well to suburban environments.
, and can be a threat to endangered species
.
(not a clear term itself) in the naturally evolved wild gene pools, many times threatening rare species with extinction
. Cases include the mallard duck, wild boar, the rock dove or pigeon, the Red Junglefowl
(Gallus gallus) (ancestor of all chickens), carp
, and more recently salmon
. Other examples of genetic pollution lie in the breeding history of dingoes. Dingoes are a canine that will interbreed with dogs of other origins, thus leading to the proliferation of dingo
hybrids and the extinction of pure wild dingoes. In some cases like rabbit
s, genetic pollution seems not to be noticed. There is much debate over the degree to which feral hybridization compromises the purity of a wild species. In the case of the mallard
, for example, some claim there are no populations that are completely free of any domestic ancestor.
and Melanesia
feral pigs constitute the primary sources of animal protein. Prior to the Wild and Free-Roaming Horses and Burros Act of 1971
, American mustangs were routinely captured and sold for horsemeat. In Australia feral goats, pigs and dromedaries are harvested for the export for their meat trade. At certain times, animals were sometimes deliberately left to go feral, typically on islands, in order to be later recovered for profit or food use for travelers (particularly sailors) at the end of a few years.
in Australia or New Zealand are currently the subject of study to determine if there is a need for their preservation.
have been protected since 1971 in part due to their romance
and connection to the history of the American West.
Tame
Tame may refer to:*Taming, the act of domesticating wild animals*River Tame, Greater Manchester*River Tame, West Midlands and the Tame Valley*Tame, Arauca, a Colombian town and municipality...
to being wild
Wildlife
Wildlife includes all non-domesticated plants, animals and other organisms. Domesticating wild plant and animal species for human benefit has occurred many times all over the planet, and has a major impact on the environment, both positive and negative....
or untamed. In the case of plants it is a movement from cultivated to uncultivated or controlled to volunteer. The introduction of feral animals or plants to their non-native regions, like any introduced species
Introduced species
An introduced species — or neozoon, alien, exotic, non-indigenous, or non-native species, or simply an introduction, is a species living outside its indigenous or native distributional range, and has arrived in an ecosystem or plant community by human activity, either deliberate or accidental...
, may disrupt ecosystem
Ecosystem
An ecosystem is a biological environment consisting of all the organisms living in a particular area, as well as all the nonliving , physical components of the environment with which the organisms interact, such as air, soil, water and sunlight....
s and has, in some cases, contributed to extinction
Extinction
In biology and ecology, extinction is the end of an organism or of a group of organisms , normally a species. The moment of extinction is generally considered to be the death of the last individual of the species, although the capacity to breed and recover may have been lost before this point...
of indigenous species. However, returning lost species to their environment can have the opposite effect, bringing damaged ecosystems back into balance.
By the same token, feral species may eliminate other "problem" species such as rodents, harmful insects, or aggressive plants.
Definitions
In addition to the meaning of the word feral described here, from Latin fera, "a wild beast", the word has a second unrelated meaning, from Latin feralis, "belonging to the dead", "funeral".Animals
One of the numerous dictionary definitions of a feral animalAnimal
Animals are a major group of multicellular, eukaryotic organisms of the kingdom Animalia or Metazoa. Their body plan eventually becomes fixed as they develop, although some undergo a process of metamorphosis later on in their life. Most animals are motile, meaning they can move spontaneously and...
states that a feral
Feral
A feral organism is one that has changed from being domesticated to being wild or untamed. In the case of plants it is a movement from cultivated to uncultivated or controlled to volunteer. The introduction of feral animals or plants to their non-native regions, like any introduced species, may...
animal is an animal which has escaped from a domestic or captive status and is living more or less as a wild animal. Other definitions realize the shortcomings of the first definition and simply say that a feral animal is an animal which has changed from being domesticated to being wild, natural, or untamed.
Zoologists generally exclude from the ‘feral’ category animals which were genuinely wild before they escaped from captivity: neither lion
Lion
The lion is one of the four big cats in the genus Panthera, and a member of the family Felidae. With some males exceeding 250 kg in weight, it is the second-largest living cat after the tiger...
s escaped from a zoo nor the sea eagle
Sea Eagle
Sea eagle mainly refers to Sea eagle, birds of prey of the genus Haliaeetus.It may also refer to:-Aerospace:* Sea Eagle , British, anti-ship missile* Sea Eagle * Supermarine Sea Eagle, 1920s British passenger flying boat-Sports:...
s (Haliaeetus albicilla) recently re-introduced into the UK are regarded as 'feral'. As far as animals are concerned, this article assumes the ‘zoological definition’ of feral. Some common examples of animals with feral populations are horses, dogs, goat
Feral goat
The feral goat is the domestic goat when it has become established in the wild. Feral goats occur in Australia, New Zealand, Ireland, Great Britain, Hawaii, the Galapagos and in many other parts of the world...
s, cats, and pigs.
The term 'feral' should not be used to describe the naturalization of a wild (i.e. non-domesticated) species. Nor should "feral" be used to describe a population of a species which although descended from a domesticated population has severed itself from dependence on humans and lived independently in the wild for a long period.
Plants
Domesticated plants that revert to wild are usually referred to as escaped, introduced or naturalized rather than feral. However, the adaptive and ecological variables seen in plants that go wild closely resemble those of animals.Susceptibility
Certain familiar animals go feral easily and successfully, while others are much less inclined to wander and usually fail promptly outside domestication.Degree
Some species will detach readily from humans and pursue their own devices, but do not stray far or spread readily. Others depart and are gone, seeking out new territory or range to exploit and displaying active invasiveness.Persistence
Whether they leave readily and venture far, the ultimate criterion for success is longevityLongevity
The word "longevity" is sometimes used as a synonym for "life expectancy" in demography or known as "long life", especially when it concerns someone or something lasting longer than expected ....
. Persistence depends on their ability to establish themselves and reproduce reliably in the new environment
Natural environment
The natural environment encompasses all living and non-living things occurring naturally on Earth or some region thereof. It is an environment that encompasses the interaction of all living species....
.
Tenure of domestication
Neither the duration nor the intensity with which a species has been domesticated offers a useful correlationCorrelation
In statistics, dependence refers to any statistical relationship between two random variables or two sets of data. Correlation refers to any of a broad class of statistical relationships involving dependence....
with its feral potential.
Examples of feral animals
The catCat
The cat , also known as the domestic cat or housecat to distinguish it from other felids and felines, is a small, usually furry, domesticated, carnivorous mammal that is valued by humans for its companionship and for its ability to hunt vermin and household pests...
returns readily to a feral state if it has not been socialized properly in its young life. (See Feral cat
Feral cat
A feral cat is a descendant of a domesticated cat that has returned to the wild. It is distinguished from a stray cat, which is a pet cat that has been lost or abandoned, while feral cats are born in the wild; the offspring of a stray cat can be considered feral if born in the wild.In many parts of...
s.) These cats, especially if left to proliferate, are frequently considered to be pests in both rural and urban areas, and may be blamed for devastating the bird
Bird
Birds are feathered, winged, bipedal, endothermic , egg-laying, vertebrate animals. Around 10,000 living species and 188 families makes them the most speciose class of tetrapod vertebrates. They inhabit ecosystems across the globe, from the Arctic to the Antarctic. Extant birds range in size from...
, reptile
Reptile
Reptiles are members of a class of air-breathing, ectothermic vertebrates which are characterized by laying shelled eggs , and having skin covered in scales and/or scutes. They are tetrapods, either having four limbs or being descended from four-limbed ancestors...
and mammal
Mammal
Mammals are members of a class of air-breathing vertebrate animals characterised by the possession of endothermy, hair, three middle ear bones, and mammary glands functional in mothers with young...
populations. A local population of feral cats living in an urban area and using a common food source is sometimes called a feral cat colony. As feral cats multiply quickly, it is difficult to control their populations. Animal shelters attempt to adopt out feral cats, especially kittens, but often are overwhelmed with sheer numbers and euthanasia
Animal euthanasia
Animal euthanasia is the act of putting to death painlessly or allowing to die, as by withholding extreme medical measures, an animal suffering from an incurable, especially a painful, disease or condition. Euthanasia methods are designed to cause minimal pain and distress...
is used. In rural areas, excessive numbers of feral cats are often shot. More recently, the "Trap-Neuter-Return
Trap-Neuter-Return
Trap-Neuter-Return , also known as Trap-Test-Vaccinate-Alter-Release is a method of humanely trapping unaltered feral cats, spaying or neutering them, and releasing them back to the same location where they were collected...
" method has been used in many locations as an alternate means of managing the feral cat population.
The goat
Goat
The domestic goat is a subspecies of goat domesticated from the wild goat of southwest Asia and Eastern Europe. The goat is a member of the Bovidae family and is closely related to the sheep as both are in the goat-antelope subfamily Caprinae. There are over three hundred distinct breeds of...
is one of the oldest domesticated creatures, yet readily goes feral and does quite well on its own.
The dromedary
Dromedary
The dromedary or Arabian camel is a large, even-toed ungulate with one hump on its back. Its native range is unclear, but it was probably the Arabian Peninsula. The domesticated form occurs widely in North Africa and the Middle East...
camel, which has been domesticated for well over 3,000 years, will also readily go feral. A substantial population
Australian feral camel
Thousands of the two main species of Australian feral camels, mostly dromedaries but also some bactrian camels, were imported into Australia during the 19th century for transport and construction as part of the colonisation of the central and western parts of Australia. Motorised transport replaced...
of feral dromedaries, descended from pack animals that escaped in the 19th and early 20th centuries, thrives in the Australia
Australia
Australia , officially the Commonwealth of Australia, is a country in the Southern Hemisphere comprising the mainland of the Australian continent, the island of Tasmania, and numerous smaller islands in the Indian and Pacific Oceans. It is the world's sixth-largest country by total area...
n interior today.
Sheep are close contemporaries and cohorts of goats in the history of domestication, but the domestic sheep is quite vulnerable to predation
Predation
In ecology, predation describes a biological interaction where a predator feeds on its prey . Predators may or may not kill their prey prior to feeding on them, but the act of predation always results in the death of its prey and the eventual absorption of the prey's tissue through consumption...
and injury, and thus rarely if ever is seen in a feral state. However, in places where there are few predators, they get on well, for example in the case of the Soay sheep
Soay sheep
The Soay sheep is a primitive breed of domestic sheep descended from a population of feral sheep on the island of Soay in the St. Kilda Archipelago, about from the Western Isles of Scotland...
.
Water buffalo
Water buffalo
The water buffalo is a domesticated bovid widely kept in Asia, Europe and South America.Water buffalo can also refer to:*Wild water buffalo , the wild ancestor of the domestic water buffalo...
run rampant in Western and Northern Australia. This is the only part of the world where they are legally hunted in their original range. The Australian government encourages the hunting of feral water buffalo because of their large numbers.
Cattle
Cattle
Cattle are the most common type of large domesticated ungulates. They are a prominent modern member of the subfamily Bovinae, are the most widespread species of the genus Bos, and are most commonly classified collectively as Bos primigenius...
have been domesticated since the neolithic
Neolithic
The Neolithic Age, Era, or Period, or New Stone Age, was a period in the development of human technology, beginning about 9500 BC in some parts of the Middle East, and later in other parts of the world. It is traditionally considered as the last part of the Stone Age...
era, but can do well enough on open range for months or even years with little or no supervision. Their ancestors, the Aurochs
Aurochs
The aurochs , the ancestor of domestic cattle, were a type of large wild cattle which inhabited Europe, Asia and North Africa, but is now extinct; it survived in Europe until 1627....
, were quite fierce, on par with the modern Cape Buffalo. Modern cattle, especially those raised on open range, are generally more docile, but when threatened can display aggression. Cattle, particularly those raised for beef
Beef
Beef is the culinary name for meat from bovines, especially domestic cattle. Beef can be harvested from cows, bulls, heifers or steers. It is one of the principal meats used in the cuisine of the Middle East , Australia, Argentina, Brazil, Europe and the United States, and is also important in...
, are often allowed to roam quite freely and have established long term independence in Australia
Australia
Australia , officially the Commonwealth of Australia, is a country in the Southern Hemisphere comprising the mainland of the Australian continent, the island of Tasmania, and numerous smaller islands in the Indian and Pacific Oceans. It is the world's sixth-largest country by total area...
, New Zealand
New Zealand
New Zealand is an island country in the south-western Pacific Ocean comprising two main landmasses and numerous smaller islands. The country is situated some east of Australia across the Tasman Sea, and roughly south of the Pacific island nations of New Caledonia, Fiji, and Tonga...
and several Pacific Islands along with small populations of semi-feral animals roaming the southwestern United States and northern Mexico
Mexico
The United Mexican States , commonly known as Mexico , is a federal constitutional republic in North America. It is bordered on the north by the United States; on the south and west by the Pacific Ocean; on the southeast by Guatemala, Belize, and the Caribbean Sea; and on the east by the Gulf of...
. Such cattle are variously called Mavericks
Maverick (animal)
Maverick is a term, usually referring to cattle, for an animal that does not carry a brand. In the period of the United States open range, such animals were relatively common. Many cows would give birth in wild or semi-wild conditions, not be located in an annual round up, and their ensuing calf...
, Scrubbers or Cleanskins. Most free roaming cattle, however untamed, are generally too valuable not to be eventually rounded up and recovered in closely settled regions.
Horse
Horse
The horse is one of two extant subspecies of Equus ferus, or the wild horse. It is a single-hooved mammal belonging to the taxonomic family Equidae. The horse has evolved over the past 45 to 55 million years from a small multi-toed creature into the large, single-toed animal of today...
s and donkey
Donkey
The donkey or ass, Equus africanus asinus, is a domesticated member of the Equidae or horse family. The wild ancestor of the donkey is the African Wild Ass, E...
s, domesticated about 5000 BCE, are feral in open grasslands worldwide (see feral horse
Feral horse
A feral horse is a free-roaming horse of domesticated ancestry. 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...
). In Portugal
Portugal
Portugal , officially the Portuguese Republic is a country situated in southwestern Europe on the Iberian Peninsula. Portugal is the westernmost country of Europe, and is bordered by the Atlantic Ocean to the West and South and by Spain to the North and East. The Atlantic archipelagos of the...
, feral horses are called Sorraia
Sorraia
The Sorraia is a rare breed of horse indigenous to the portion of the Iberian peninsula known today as Portugal. The Sorraia is known for its primitive features, including a convex profile and dun coloring with primitive markings...
; in Australia
Australia
Australia , officially the Commonwealth of Australia, is a country in the Southern Hemisphere comprising the mainland of the Australian continent, the island of Tasmania, and numerous smaller islands in the Indian and Pacific Oceans. It is the world's sixth-largest country by total area...
, they are called Brumbies
Brumby
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 in south-eastern Australia. Today, most of them are found in the Northern Territory, with the second largest population in Queensland...
; in the American
United States
The United States of America is a federal constitutional republic comprising fifty states and a federal district...
west, they are called Mustangs
Mustang (horse)
A Mustang is a free-roaming horse of the North American west that first descended from horses brought to the Americas by the Spanish. Mustangs are often referred to as wild horses, but there is intense debate over terminology...
. Other isolated feral populations exist, including the Chincoteague Pony
Chincoteague Pony
The Chincoteague Pony, also known as the Assateague horse, is a breed of pony that developed and lives in a feral condition on Assateague Island in the United States states of Virginia and Maryland. The breed was made famous by the Misty of Chincoteague series written by Marguerite Henry starting...
and the Banker Horse
Banker Horse
The Banker horse is a breed of feral horse living on the islands of North Carolina's Outer Banks. It is small, hardy, and has a docile temperament...
. They are often referred to as "wild horse
Wild Horse
The wild horse is a species of the genus Equus, which includes as subspecies the domesticated horse as well as the undomesticated Tarpan and Przewalski's Horse. The Tarpan became extinct in the 19th century, and Przewalski's Horse was saved from the brink of extinction and reintroduced...
s," but this is a misnomer. There are truly "wild" horses that have never been tamed, most notably Przewalski's Horse
Przewalski's Horse
Przewalski's Horse or Dzungarian Horse, is a rare and endangered subspecies of wild horse native to the steppes of central Asia, specifically China and Mongolia.At one time extinct in the wild, it has been reintroduced to its native habitat in Mongolia at the Khustain Nuruu...
. While the horse was originally indigenous to North America, the wild ancestor died out at the end of the last Ice Age
Ice age
An ice age or, more precisely, glacial age, is a generic geological period of long-term reduction in the temperature of the Earth's surface and atmosphere, resulting in the presence or expansion of continental ice sheets, polar ice sheets and alpine glaciers...
. In both Australia and the Americas, modern "wild" horses descended from domesticated horses brought by European explorers and settlers that escaped, spread, and thrived.
The pig
Pig
A pig is any of the animals in the genus Sus, within the Suidae family of even-toed ungulates. Pigs include the domestic pig, its ancestor the wild boar, and several other wild relatives...
(hog) has established feral populations worldwide, most notably in Australia, New Zealand, the United States, New Guinea
New Guinea
New Guinea is the world's second largest island, after Greenland, covering a land area of 786,000 km2. Located in the southwest Pacific Ocean, it lies geographically to the east of the Malay Archipelago, with which it is sometimes included as part of a greater Indo-Australian Archipelago...
and the Pacific Islands. Pigs were introduced to the Melanesian and Polynesian regions by humans from several thousand to five hundred years ago, and to Australia and the Americas within the past 500 years. While pigs were doubtlessly brought to New Zealand by the original Polynesian settlers, this population had become extinct by the time of European colonization, and all feral pigs in New Zealand today are descendants of European stock. Many European wild boar populations are also partially descended from escaped domestic pigs and are thus technically feral animals within the native range of the ancestral species.
Rock Pigeon
Rock Pigeon
The Rock Dove or Rock Pigeon, is a member of the bird family Columbidae . In common usage, this bird is often simply referred to as the "pigeon"....
s were formerly kept for their meat
Meat
Meat is animal flesh that is used as food. Most often, this means the skeletal muscle and associated fat and other tissues, but it may also describe other edible tissues such as organs and offal...
or more commonly as racing animals and have established feral populations
Feral Pigeon
Feral pigeons , also called city doves, flying rats, city pigeons or street pigeons, are derived from domestic pigeons that have returned to the wild. The domestic pigeon was originally bred from the wild Rock Pigeon, which naturally inhabits sea-cliffs and mountains. All three types readily...
in cities worldwide.
Colonies of honey bees often escape into the wild from managed apiaries
Apiary
An apiary is a place where beehives of honey bees are kept. Traditionally beekeepers paid land rent in honey for the use of small parcels. Some farmers will provide free apiary sites, because they need pollination, and farmers who need many hives often pay for them to be moved to the crops when...
when they swarm; their behavior, however, is no different from their behavior "in captivity", until and unless they breed with other feral honey bees of a different genetic stock, which may lead them to become more docile or more aggressive (see Africanized bee
Africanized bee
Africanized honey bees, known colloquially as "killer bees", are a hybrid variety of the European honeybee , generated by a man-made breeding of the African honey bee, A. m. scutellata, with various European honey bees such as the Italian bee A. m. ligustica and A. m. iberiensis. These bees are far...
s).
Large colonies of feral parrots
Feral parrots
A feral parrot is a parrot that has adapted to life in an ecosystem to which it is not native.-Rainbow Lorikeet:Feral colonies of Rainbow Lorikeet have been established in Perth, Western Australia and in Auckland, New Zealand....
are present in various parts of the world, with Rose-ringed Parakeet
Rose-ringed Parakeet
The Rose-ringed Parakeet , also known as the Ringnecked Parakeet, is a gregarious tropical parakeet species that has an extremely large range. Since the trend of the population appears to be increasing, the species has been evaluated as Least Concern by IUCN in 2009.Rose-ringed parakeets are...
s, Monk Parakeet
Monk Parakeet
The Monk Parakeet, also known as the Quaker Parrot, is a species of parrot, in most treatments the only member of the genus Myiopsitta. It originates from the temperate to subtropical areas of Argentina and the surrounding countries in South America...
s and Red-masked Parakeet
Red-masked Parakeet
The Red-masked Parakeet, Aratinga erythrogenys, is a medium-sized parrot from Ecuador and Peru. It is popular as a pet and considered a good talker. It is known in aviculture as the Cherry-headed Conure.-Description:...
s (the latter of which became the subject of the documentary film, The Wild Parrots of Telegraph Hill
The Wild Parrots of Telegraph Hill
The Wild Parrots of Telegraph Hill is a 2005 documentary film directed, produced, and edited by Judy Irving. It chronicles the relationship between Mark Bittner, an unemployed musician who is living rent-free in a cabin in Telegraph Hill in San Francisco, California, and a flock of feral parrots ...
) being particularly successful outside of their native habitats and adapting well to suburban environments.
Harmful and beneficial effects of feralization
Ecological impact
A feral population can have a significant impact on an ecosystem by predation on vulnerable plants or animals, or by competition with indigenous species. Feral plants and animals constitute a significant share of invasive speciesInvasive species
"Invasive species", or invasive exotics, is a nomenclature term and categorization phrase used for flora and fauna, and for specific restoration-preservation processes in native habitats, with several definitions....
, and can be a threat to endangered species
Endangered species
An endangered species is a population of organisms which is at risk of becoming extinct because it is either few in numbers, or threatened by changing environmental or predation parameters...
.
Genetic pollution
Animals of domestic origin sometimes can produce fertile hybrids with native, wild animals which leads to genetic pollutionGenetic pollution
Genetic pollution is a controversial term for uncontrolled gene flow into wild populations. This gene flow is undesirable according to some environmentalists and conservationists, including groups such as Greenpeace, TRAFFIC, and GeneWatch UK.-Usage:...
(not a clear term itself) in the naturally evolved wild gene pools, many times threatening rare species with extinction
Extinction
In biology and ecology, extinction is the end of an organism or of a group of organisms , normally a species. The moment of extinction is generally considered to be the death of the last individual of the species, although the capacity to breed and recover may have been lost before this point...
. Cases include the mallard duck, wild boar, the rock dove or pigeon, the Red Junglefowl
Red Junglefowl
The Red Junglefowl is a tropical member of the Pheasant family. They are thought to be ancestors of the domestic chicken with some hybridisation with the Grey Junglefowl...
(Gallus gallus) (ancestor of all chickens), carp
Carp
Carp are various species of oily freshwater fish of the family Cyprinidae, a very large group of fish native to Europe and Asia. The cypriniformes are traditionally grouped with the Characiformes, Siluriformes and Gymnotiformes to create the superorder Ostariophysi, since these groups have certain...
, and more recently salmon
Salmon
Salmon is the common name for several species of fish in the family Salmonidae. Several other fish in the same family are called trout; the difference is often said to be that salmon migrate and trout are resident, but this distinction does not strictly hold true...
. Other examples of genetic pollution lie in the breeding history of dingoes. Dingoes are a canine that will interbreed with dogs of other origins, thus leading to the proliferation of dingo
Dingo
The Australian Dingo or Warrigal is a free-roaming wild dog unique to the continent of Australia, mainly found in the outback. Its original ancestors are thought to have arrived with humans from southeast Asia thousands of years ago, when dogs were still relatively undomesticated and closer to...
hybrids and the extinction of pure wild dingoes. In some cases like rabbit
Rabbit
Rabbits are small mammals in the family Leporidae of the order Lagomorpha, found in several parts of the world...
s, genetic pollution seems not to be noticed. There is much debate over the degree to which feral hybridization compromises the purity of a wild species. In the case of the mallard
Mallard
The Mallard , or Wild Duck , is a dabbling duck which breeds throughout the temperate and subtropical Americas, Europe, Asia, and North Africa, and has been introduced to New Zealand and Australia....
, for example, some claim there are no populations that are completely free of any domestic ancestor.
Zoonotic potential
Feral animals may become reservoirs of diseases and transmit them to humans. The spread of rabies from feral dogs and cats is a very grave threat. There is a need to have effective control measures especially of feral dog and cat populations.Economic harm
Feral animals compete with domestic livestock, and may degrade fences, water sources, and vegetation (by overgrazing or introducing seeds of invasive plants). Though hotly disputed, some cite as an example the competition between feral horses and cattle in the western United States. Another example is of goats competing with cattle in Australia, or goats that degrade trees and vegetation in environmentally-stressed regions of Africa. Accidental crossbreeding by feral animals may result in harm to breeding programs of pedigreed animals; their presence may also excite domestic animals and push them to escape. Feral populations can also pass on transmissible infections to domestic herds. Loss to farmers by aggressive feral dog population is common in India.Economic benefits
Many feral animals can sometimes be captured at little cost and thus constitute a significant resource. Throughout most of PolynesiaPolynesia
Polynesia is a subregion of Oceania, made up of over 1,000 islands scattered over the central and southern Pacific Ocean. The indigenous people who inhabit the islands of Polynesia are termed Polynesians and they share many similar traits including language, culture and beliefs...
and Melanesia
Melanesia
Melanesia is a subregion of Oceania extending from the western end of the Pacific Ocean to the Arafura Sea, and eastward to Fiji. The region comprises most of the islands immediately north and northeast of Australia...
feral pigs constitute the primary sources of animal protein. Prior to the Wild and Free-Roaming Horses and Burros Act of 1971
Wild and Free-Roaming Horses and Burros Act of 1971
The Wild and Free-Roaming Horses and Burros Act of 1971 , is an Act of Congress , signed into law President Richard M. Nixon on December 18, 1971...
, American mustangs were routinely captured and sold for horsemeat. In Australia feral goats, pigs and dromedaries are harvested for the export for their meat trade. At certain times, animals were sometimes deliberately left to go feral, typically on islands, in order to be later recovered for profit or food use for travelers (particularly sailors) at the end of a few years.
Scientific value
Populations of feral animals present good sources for studies of population dynamics, and especially of ecology and behavior (ethology) in a wild state of species known mainly in a domestic state. Such observations can provide useful information for the stock breeders or other owners of the domesticated conspecifics (i.e. animals of the same species).Genetic diversity
Feral populations sometimes preserve or develop characteristics which do not always exist in the fully domesticated equivalent. Therefore, they contribute to domestic biodiversity and often deserve to be preserved, be it in their feral environment or as domestic animals. For example, feral species that are usually subjects of eradicationEradication
Eradication may also refer to:*Genocide, the deliberate, systematic destruction of an ethnic, religious or national group of people*Eradication of infectious diseases, the reduction of the global prevalence of an infectious disease in its human or animal host to zero*Intentional local extinction,...
in Australia or New Zealand are currently the subject of study to determine if there is a need for their preservation.
Cultural or historic value
American MustangsMustang (horse)
A Mustang is a free-roaming horse of the North American west that first descended from horses brought to the Americas by the Spanish. Mustangs are often referred to as wild horses, but there is intense debate over terminology...
have been protected since 1971 in part due to their romance
Romanticism
Romanticism was an artistic, literary and intellectual movement that originated in the second half of the 18th century in Europe, and gained strength in reaction to the Industrial Revolution...
and connection to the history of the American West.
See also
- Abandoned petsAbandoned petsAbandoned pets are pets that are, for instance, left behind when a home goes into foreclosure or their owner passes away. These animals can be left alone on the property or dropped off at a shelter. While some are left in a shelter, they are typically discovered after the foreclosure process when...
- DomesticationDomesticationDomestication or taming is the process whereby a population of animals or plants, through a process of selection, becomes accustomed to human provision and control. In the Convention on Biological Diversity a domesticated species is defined as a 'species in which the evolutionary process has been...
- EstrayEstrayEstray, in law, is any domestic animal found wandering at large or lost, particularly if the owner is unknown.Under early English common law, estrays were forfeited to the king or lord of the manor; under modern statutes, provision is made for taking up stray animals and acquiring either title to...
- Feral children
- Feral (subculture)Feral (subculture)The feral subculture is a counter-cultural social movement originating in the latter part of the twentieth century, mainly centered in Australasia. The movement reached its heyday in the mid 1990s, in parallel with other similar movements in Europe and elsewhere...
- Invasive speciesInvasive species"Invasive species", or invasive exotics, is a nomenclature term and categorization phrase used for flora and fauna, and for specific restoration-preservation processes in native habitats, with several definitions....
- Overpopulation in companion animals
- Stray dogs in BangkokStray dogs in BangkokIt is estimated that there are over 120,000 stray dogs in Bangkok, Thailand. The management of these so-called soi dogs has become a serious problem in the capital.-Status:...
External links
Note: Links that treat feral animals as a mere pest issue are the norm.- National Wild Horse and Burro Program
- Feral Camels, Information from Australian Department of Agriculture regarding Australia's estimated 300,000 feral camels.
- Alley Cat Allies, a feral cat advocacy organization