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103-501: Today, the Welsh Harlequin is a light-weight duck breed known for its vivid plumage and egg laying ability. Over the years the colour and conformation of the breed has changed, indicating that likely new blood of another breed has been introduced. Welsh Harlequins weigh 4.5 to 5.5 pounds (2-2.5 kilos). Females have a black bill and brown legs and feet, and their plumage is similar to a mallard but heavily frosted with white. They also lack

206-591: A regional accent , with urban mallards in London being much louder and more vociferous compared to rural mallards in Cornwall , serving as an adaptation to persistent levels of anthropogenic noise. When incubating a nest, or when offspring are present, females vocalise differently, making a call that sounds like a truncated version of the usual quack. This maternal vocalisation is highly attractive to their young. The repetition and frequency modulation of these quacks form

309-816: A speculum on their wings; males especially tend to have blue speculum feathers. The mallard is 50–65 cm (20–26 in) long, of which the body makes up around two-thirds the length. The wingspan is 81–98 cm (32–39 in) and the bill is 4.4 to 6.1 cm (1.7 to 2.4 in) long. It is often slightly heavier than most other dabbling ducks, weighing 0.7–1.6 kg (1.5–3.5 lb). Mallards live in wetlands , eat water plants and small animals, and are social animals preferring to congregate in groups or flocks of varying sizes. The female lays 8 to 13 creamy white to greenish-buff spotless eggs , on alternate days. Incubation takes 27 to 28 days and fledging takes 50 to 60 days. The ducklings are precocial and fully capable of swimming as soon as they hatch. The mallard

412-681: A 'late' clutch occurred in November 2011, in which a female successfully hatched and raised a clutch of eleven ducklings at the London Wetland Centre . During the breeding season, both male and female mallards can become aggressive, driving off competitors to themselves or their mate by charging at them. Males tend to fight more than females and attack each other by repeatedly pecking at their rival's chest, ripping out feathers and even skin on rare occasions. Female mallards are also known to carry out 'inciting displays', which encourage other ducks in

515-609: A brood of ducklings. Nesting sites are typically on the ground, hidden in vegetation where the female's speckled plumage serves as effective camouflage , but female mallards have also been known to nest in hollows in trees, boathouses, roof gardens and on balconies, sometimes resulting in hatched offspring having difficulty following their parent to water. Egg clutches number 8–13 creamy white to greenish-buff eggs free of speckles. They measure about 58 mm (2.3 in) in length and 32 mm (1.3 in) in width. The eggs are laid on alternate days, and incubation begins when

618-492: A combination of hot temperatures and reduced water levels place mallards at an increased risk of contracting botulism , as these conditions are ideal for Clostridium botulinum to propagate, with the birds also more likely to come into contact with botulinum toxin produced by the bacteria. Outbreaks of botulism among mallard populations can lead to mass die-offs. The predation-avoidance behaviour of sleeping with one eye open, allowing one brain hemisphere to remain aware while

721-425: A dark spot at the tip of the bill. The birds produce a lean carcass and are active foragers, though they are sometimes more vulnerable to predators such as birds of prey due to their light colouration. The egg laying ability is highly valued as the production exhibited by some ducks rivals that of hens. The breed is prone to broodiness and a pair can easily produce young without human interference. They have become

824-529: A darker crown and eye-stripe. Mallards, like other sexually-dimorphic birds, can sometimes go though spontaneous sex reversal, often caused by damaged or nonfunctioning sex organs, such as the ovaries in mallard hens. This phenomenon can cause female mallards to exhibit male plumage, and vice versa (phenotypic feminisation or masculinisation). Both male and female mallards have distinct iridescent purple-blue speculum feathers edged with white, which are prominent in flight or at rest but temporarily shed during

927-505: A few blood vessels to prevent heat loss, and, as in the Greenland mallard, the bill is smaller than that of birds farther south, illustrating the rule. Due to the variability of the mallard's genetic code, which gives it its vast interbreeding capability, mutations in the genes that decide plumage colour are very common and have resulted in a wide variety of hybrids, such as Brewer's duck (mallard × gadwall, Mareca strepera ). The mallard

1030-669: A few metres deep. They are attracted to bodies of water with aquatic vegetation. The mallard is omnivorous and very flexible in its choice of food. Its diet may vary based on several factors, including the stage of the breeding cycle, short-term variations in available food, nutrient availability, and interspecific and intraspecific competition . The majority of the mallard's diet seems to be made up of gastropods , insects (including beetles, flies, lepidopterans , dragonflies , and caddisflies ), crustaceans , other arthropods , worms, feces of other birds, many varieties of seeds and plant matter, and roots and tubers . During

1133-404: A glass window. This paper was awarded an Ig Nobel Prize in 2003. Mallards are opportunistically targeted by brood parasites , occasionally having eggs laid in their nests by redheads , ruddy ducks , lesser scaup , gadwalls , northern shovellers , northern pintails , cinnamon teal , common goldeneyes , and other mallards. These eggs are generally accepted when they resemble the eggs of

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1236-566: A laboratory, and therefore distinct from those that were bred through artificial selection. In the fields of agriculture , agroforestry and animal husbandry , genetic pollution is being used to describe gene flows between GE species and wild relatives. An early use of the term " genetic pollution" in this later sense appears in a wide-ranging review of the potential ecological effects of genetic engineering in The Ecologist magazine in July 1989 . It

1339-431: A loss of fitness in the wild populations. The term can be associated with the gene flow from a mutation bred , synthetic organism or genetically engineered organism to a non GE organism, by those who consider such gene flow detrimental. These environmentalist groups stand in complete opposition to the development and production of genetically engineered organisms. From a governmental perspective, genetic pollution

1442-443: A major cause of extinction throughout the world in the past few hundred years. Some of them prey on native wildlife, compete with it for resources, or spread disease, while others may hybridize with native species, causing " genetic pollution ". In these ways, invasive species are as big a threat to the balance of nature as the direct overexploitation by humans of some species. " It can also be considered undesirable if it leads to

1545-447: A mallard) to huge bald ( Haliaeetus leucocephalus ) and golden eagles ( Aquila chrysaetos ), and about a dozen species of mammalian predators, not counting several more avian and mammalian predators who threaten eggs and nestlings. Mallards are also preyed upon by other waterside apex predators , such as grey herons ( Ardea cinerea ), great blue herons ( Ardea herodias ) and black-crowned night herons ( Nycticorax nycticorax ),

1648-835: A popular backyard pet in recent years due to the bird's calm demeanor and high egg production. The Welsh Harlequin was admitted to the American Poultry Association 's Standard of Perfection in 2001. As of 2016 the Welsh Harlequin in North America has jumped from critical to watched by the American Livestock Breeds Conservancy . Mallard A. p. platyrhynchos Linnaeus, 1758 A. p. domesticus Linnaeus, 1758 A. p. conboschas C. L. Brehm , 1831 (disputed) [REDACTED] The mallard ( / ˈ m æ l ɑːr d , ˈ m æ l ər d / ) or wild duck ( Anas platyrhynchos )

1751-527: A river bank, but not always near water. It is highly gregarious outside of the breeding season and forms large flocks , which are known as "sordes". Mallards usually form pairs (in October and November in the Northern Hemisphere) until the female lays eggs at the start of the nesting season, which is around the beginning of spring. At this time she is left by the male who joins up with other males to await

1854-441: A separate subspecies, the Greenland mallard ( A.   p.   conboschas ). The mallard is a medium-sized waterfowl species that is often slightly heavier than most other dabbling ducks. It is 50–65 cm (20–26 in) long – of which the body makes up around two-thirds – has a wingspan of 81–98 cm (32–39 in), and weighs 0.7–1.6 kg (1.5–3.5 lb). Among standard measurements,

1957-432: A sequence of 2-10 quacks in a row, starting loud and with the volume gradually decreasing. Male mallards make a sound phonetically similar to that of the female, a typical quack , but it is deeper and quieter compared to that of the female. Research conducted by Middlesex University on two English mallard populations found that the vocalisations of the mallard varies depending on their environment and have something akin to

2060-522: A severe threat to indigenous waterfowl's genetic integrity. Mallards and their hybrids compete with indigenous birds for resources, including nest sites, roosting sites, and food. Availability of mallards, mallard ducklings, and fertilised mallard eggs for public sale and private ownership, either as poultry or as pets, is currently legal in the United States, except for the state of Florida , which has currently banned domestic ownership of mallards. This

2163-436: A significant risk to wild populations. Crops refer to groups of plants grown for consumption. Despite domestication over many years, these plants are not so far removed from their wild relatives that they couldn't reproduce if brought together. Many crops are still grown in the areas they originated and gene flow between crops and wild relatives impacts the evolution of wild populations. Farmers can avoid reproduction between

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2266-747: A strong flavour. They were first domesticated in Southeast Asia at least 4,000 years ago, during the Neolithic Age , and were also farmed by the Romans in Europe, and the Malays in Asia . As the domestic duck and the mallard are the same species as each other, it is common for mallards to mate with domestic ducks and produce hybrid offspring that are fully fertile. Because of this, mallards have been found to be contaminated with

2369-418: A very small and fluctuating population. Mallards sometimes arrive on its island home during migration, and can be expected to occasionally have remained and hybridised with Laysan ducks as long as these species have existed. However, these hybrids are less well adapted to the peculiar ecological conditions of Laysan Island than the local ducks, and thus have lower fitness . Laysan ducks were found throughout

2472-506: A white square on the wings in flight, and is a smaller bird. More similar to the female mallard in North America are the American black duck ( A.   rubripes ), which is notably darker-hued in both sexes than the mallard, and the mottled duck ( A.   fulvigula ), which is somewhat darker than the female mallard, and with slightly different bare-part colouration and no white edge on

2575-399: A wolf.'" Aquaculture is the practice of farming aquatic animals or plants for the purpose of consumption. This practice is becoming increasingly common for the production of salmon . This is specifically termed aquaculture of salmonoids . One of the dangers of this practice is the possibility of domesticated salmon breaking free from their containment. The occurrence of escaping incidents

2678-597: Is a dabbling duck that breeds throughout the temperate and subtropical Americas , Eurasia , and North Africa . It has been introduced to New Zealand, Australia, Peru, Brazil, Uruguay, Argentina, Chile, Colombia, the Falkland Islands, and South Africa. This duck belongs to the subfamily Anatinae of the waterfowl family Anatidae . Males (drakes) have green heads, while the females (hens) have mainly brown-speckled plumage . Both sexes have an area of white-bordered black or iridescent purple or blue feathers called

2781-411: Is a term for uncontrolled gene flow into wild populations. It is defined as "the dispersal of contaminated altered genes from genetically engineered organisms to natural organisms, esp. by cross-pollination", but has come to be used in some broader ways. It is related to the population genetics concept of gene flow, and genetic rescue , which is genetic material intentionally introduced to increase

2884-429: Is becoming increasingly common as aquaculture gains popularity. Farming structures may be ineffective at holding the vast number of fast growing animals they house. Natural disasters, high tides, and other environmental occurrences can also trigger aquatic animal escapes. The reason these escapes are considered dangers is the impact they pose for the wild population they reproduce with after escaping. In many instances

2987-400: Is believed that these beetles were introduced through cargo at trade ports. The beetles are highly damaging to the environment, and are estimated to cause risk to 35% of urban trees, excluding natural forests. These beetles cause severe damage to the wood of trees by larval funneling. Their presence in the ecosystem destabilizes community structure, having a negative influence on many species in

3090-667: Is considered to be a species of least concern by the International Union for Conservation of Nature (IUCN). Unlike many waterfowl, mallards are considered an invasive species in some regions. It is a very adaptable species, being able to live and even thrive in urban areas which may have supported more localised, sensitive species of waterfowl before development. The non-migratory mallard interbreeds with indigenous wild ducks of closely related species through genetic pollution by producing fertile offspring. Complete hybridisation of various species of wild duck gene pools could result in

3193-471: Is currently introgressing into the mallard populations of the Primorsky Krai , possibly due to habitat changes from global warming . The Mariana mallard was a resident allopatric population – in most respects a good species – apparently initially derived from mallard-Pacific black duck hybrids; it became extinct in the late 20th century. The Laysan duck is an insular relative of the mallard, with

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3296-697: Is defined as follows by the Food and Agriculture Organization of the United Nations : "Uncontrolled spread of genetic information (frequently referring to transgenes) into the genomes of organisms in which such genes are not present in nature." Use of the term 'genetic pollution' and similar phrases such as genetic deterioration , genetic swamping , genetic takeover , and genetic aggression , are being debated by scientists as many do not find it scientifically appropriate. Rhymer and Simberloff argue that these types of terms: ...imply either that hybrids are less fit than

3399-499: Is little evidence that yields actually increase. While scientists are concerned genetically engineered organisms can have negative effects on surrounding plant and animal communities, the risk of gene flow between genetically engineered organisms and wild populations is yet another concern. Many farmed crops may be weed resistant and reproduce with wild relatives. More research is necessary to understand how much gene flow between genetically engineered crops and wild populations occurs, and

3502-421: Is meant to convey the idea that mixing genetic information is bad for the environment. However, because the mixing of genetic information can lead to a variety of outcomes, "pollution" may not be the most accurate descriptor. Gene flow is undesirable according to some environmentalists and conservationists , including groups such as Greenpeace , TRAFFIC , and GeneWatch UK . " Invasive species have been

3605-416: Is mitigation. Mitigation involves linking the positive trait (beneficial to fitness) to a trait that is negative (harmful to fitness) to wild but not domesticated individuals. In this case, if the protection trait was introduced to a weed, the negative trait would also be introduced in order to decrease overall fitness of the weed and decrease possibility of the individual’s reproduction and thus propagation of

3708-420: Is more a consequence of local ducks declining than of mallards spreading; allopatric speciation and isolating behaviour have produced today's diversity of mallard-like ducks despite the fact that, in most, if not all, of these populations, hybridisation must have occurred to some extent. Mallards are causing severe "genetic pollution" to South Africa's biodiversity by breeding with endemic ducks even though

3811-635: Is not warranted a vulnerable rating. Also, the population size of the mallard is very large. Unlike many waterfowl, mallards have benefited from human alterations to the world – so much so that they are now considered an invasive species in some regions. They are a common sight in urban parks, lakes, ponds, and other human-made water features in the regions they inhabit, and are often tolerated or encouraged in human habitat due to their placid nature towards humans and their beautiful and iridescent colours. While most are not domesticated, mallards are so successful at coexisting in human regions that

3914-547: Is one that is not native to a given population that is either intentionally or accidentally brought into a given ecosystem. Effects of introduction are highly variable, but if an introduced species has a major negative impact on its new environment, it can be considered an invasive species. One such example is the introduction of the Asian Longhorned beetle in North America, which was first detected in 1996 in Brooklyn, New York. It

4017-520: Is sometimes still used this way. It was derived from the Old French malart or mallart for "wild drake" although its true derivation is unclear. It may be related to, or at least influenced by, an Old High German masculine proper name Madelhart , clues lying in the alternative English forms "maudelard" and "mawdelard". Masle (male) has also been proposed as an influence. Mallards frequently interbreed with their closest relatives in

4120-622: Is somewhat shallow where the birds can be found foraging for food. Hunting mallards might cause the population to decline in some places, at some times, and with some populations. In certain countries, the mallard may be legally shot but is protected under national acts and policies. For example, in the United Kingdom, the mallard is protected under the Wildlife and Countryside Act 1981 , which restricts certain hunting methods or taking or killing mallards. Genetic pollution Genetic pollution

4223-571: Is the international wildlife trade monitoring network that works to limit trade in wild plants and animals so that it is not a threat to conservationist goals. They promote awareness of the effects of introduced invasive species that may " hybridize with native species, causing genetic pollution ". Furthermore, the Joint Nature Conservation Committee , the statutory adviser to the UK government , has stated that invasive species "will alter

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4326-584: Is to prevent hybridisation with the native mottled duck . The mallard is considered an invasive species in Australia and New Zealand, where it competes with the Pacific black duck (known as the grey duck locally in New Zealand) which was over-hunted in the past. There, and elsewhere, mallards are spreading with increasing urbanisation and hybridising with local relatives. The eastern or Chinese spot-billed duck

4429-630: Is widely distributed across the Northern and Southern Hemispheres; in North America its range extends from southern and central Alaska to Mexico, the Hawaiian Islands , across the Palearctic , from Iceland and southern Greenland and parts of Morocco ( North Africa ) in the west, Scandinavia and Britain to the north, and to Siberia, Japan, and South Korea. Also in the east, it ranges to south-eastern and south-western Australia and New Zealand in

4532-575: The Agreement on the Conservation of African-Eurasian Migratory Waterbirds – an agreement to protect the local waterfowl populations – applies to the mallard as well as other ducks. The hybrids of mallards and the yellow-billed duck are fertile, capable of producing hybrid offspring. If this continues, only hybrids occur and in the long term result in the extinction of various indigenous waterfowl. The mallard can crossbreed with 63 other species, posing

4635-766: The D-loop sequence suggest that mallards may have evolved in the general area of Siberia . Mallard bones rather abruptly appear in food remains of ancient humans and other deposits of fossil bones in Europe , without a good candidate for a local predecessor species . The large Ice Age palaeosubspecies that made up at least the European and West Asian populations during the Pleistocene has been named Anas platyrhynchos palaeoboschas . Mallards are differentiated in their mitochondrial DNA between North American and Eurasian populations, but

4738-579: The European herring gull ( Larus argentatus ), the wels catfish ( Silurus glanis ), and the northern pike ( Esox lucius ). Crows ( Corvus   spp. ) are also known to kill ducklings and adults on occasion. Also, mallards may be attacked by larger anseriformes such as swans ( Cygnus   spp. ) and geese during the breeding season, and are frequently driven off by these birds over territorial disputes. Mute swans ( Cygnus olor ) have been known to attack or even kill mallards if they feel that

4841-811: The Old World mallards and the New World mallard demonstrates the extent to which the genome is shared among them such that birds like the Chinese spot-billed duck are highly similar to the Old World mallard, and birds such as the Hawaiian duck are highly similar to the New World mallard. The size of the mallard varies clinally ; for example, birds from Greenland , though larger, have smaller bills, paler plumage, and stockier bodies than birds further south and are sometimes classified as

4944-770: The genus Anas , such as the American black duck , and also with species more distantly related, such as the northern pintail , leading to various hybrids that may be fully fertile. The mallard has hybridised with more than 40 species in the wild, and an additional 20 species in captivity, though fertile hybrids typically have two Anas parents. Mallards and their domestic conspecifics are fully interfertile; many wild mallard populations in North America contain significant amounts of domestic mallard DNA. Genetic analysis has shown that certain mallards appear to be closer to their Indo-Pacific relatives, while others are related to their American relatives. Mitochondrial DNA data for

5047-402: The wing chord is 25.7 to 30.6 cm (10.1 to 12.0 in), the bill is 4.4 to 6.1 cm (1.7 to 2.4 in), and the tarsus is 4.1 to 4.8 cm (1.6 to 1.9 in). The breeding male mallard is unmistakable, with a glossy bottle-green head and a white collar that demarcates the head and neck from the purple-tinged brown breast, grey-brown wings, and a pale grey belly. The rear of

5150-402: The Greenland mallard which is larger than the mallards further south. Allen's Rule says that appendages like ears tend to be smaller in polar forms to minimise heat loss, and larger in tropical and desert equivalents to facilitate heat diffusion, and that the polar taxa are stockier overall. Examples of this rule in birds are rare as they lack external ears, but the bill of ducks is supplied with

5253-509: The Hawaiian archipelago before 400   AD, after which they suffered a rapid decline during the Polynesian colonisation. Now, their range includes only Laysan Island. It is one of the successfully translocated birds, after having become nearly extinct in the early 20th century. Mallards have often been ubiquitous in their regions among the ponds, rivers, and streams of human parks, farms, and other human-made waterways – even to

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5356-516: The Southern hemisphere. It is strongly migratory in the northern parts of its breeding range, and winters farther south. For example, in North America, it winters south to the southern United States and northern Mexico , but also regularly strays into Central America and the Caribbean between September and May. A drake later named "Trevor" attracted media attention in 2018 when it turned up on

5459-460: The annual summer moult. Upon hatching, the plumage of the duckling is yellow on the underside and face (with streaks by the eyes) and black on the back (with some yellow spots) all the way to the top and back of the head. Its legs and bill are also black. As it nears a month in age, the duckling's plumage starts becoming drab, looking more like the female, though more streaked, and its legs lose their dark grey colouring. Two months after hatching,

5562-535: The auditory basis for species identification in offspring, a process known as acoustic conspecific identification. In addition, females hiss if the nest or offspring are threatened or interfered with. When taking off, the wings of a mallard produce a characteristic faint whistling noise. The mallard is a rare example of both Allen's Rule and Bergmann's Rule in birds. Bergmann's Rule, which states that polar forms tend to be larger than related ones from warmer climates, has numerous examples in birds, as in case of

5665-408: The beginning and the end of the summer moulting period. The adulthood age for mallards is fourteen months, and the average life expectancy is three years, but they can live to twenty. Several species of duck have brown-plumaged females that can be confused with the female mallard. The female gadwall ( Mareca strepera ) has an orange-lined bill, white belly, black and white speculum that is seen as

5768-400: The breeding season, male birds were recorded to have eaten 37.6% animal matter and 62.4% plant matter, most notably the grass Echinochloa crus-galli , and nonlaying females ate 37.0% animal matter and 63.0% plant matter, while laying females ate 71.9% animal matter and only 28.1% plant matter. Plants generally make up the larger part of a bird's diet, especially during autumn migration and in

5871-455: The centre tail feather (drake feather) is curled, but in females, the centre tail feather is straight. During the final period of maturity leading up to adulthood (6–10 months of age), the plumage of female juveniles remains the same while the plumage of male juveniles gradually changes to its characteristic colours. This change in plumage also applies to adult mallard males when they transition in and out of their non-breeding eclipse plumage at

5974-841: The clutch is almost complete. Incubation takes 27–28   days and fledging takes 50–60   days. The ducklings are precocial and fully capable of swimming as soon as they hatch. However, filial imprinting compels them to instinctively stay near the mother, not only for warmth and protection but also to learn about and remember their habitat as well as how and where to forage for food. Though adoptions are known to occur, female mallards typically do not tolerate stray ducklings near their broods, and will violently attack and drive away any unfamiliar young, sometimes going as far as to kill them. When ducklings mature into flight-capable juveniles, they learn about and remember their traditional migratory routes (unless they are born and raised in captivity). In New Zealand, where mallards are naturalised ,

6077-512: The different populations by timing their planting of crops so that crops are not flowering when wild relatives would be. Domesticated crops have been changed through artificial selection and genetic engineering. The genetic make-ups of many crops is different from those of their wild relatives, but the closer they grow to one another the more likely they are to share genes through pollen. Gene flow persists between crops and wild counterparts. Genetically engineered organisms are genetically modified in

6180-475: The ducks pose a threat to their offspring. Common loons ( Gavia inmer ) are similarly territorial and aggressive towards other birds in such disputes, and will frequently drive mallards away from their territory. However, in 2019, a pair of common loons in Wisconsin were observed raising a mallard duckling for several weeks, having seemingly adopted the bird after it had been abandoned by its parents. In summer,

6283-399: The effects of introduced invasive species that may " hybridize with native species, causing genetic pollution ". In the fields of agriculture , agroforestry and animal husbandry , genetic pollution is used to describe gene flows between genetically engineered species and wild relatives. The use of the word "pollution" is meant to convey the idea that mixing genetic information is bad for

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6386-474: The environment, but because the mixing of genetic information can lead to a variety of outcomes, "pollution" may not always be the most accurate descriptor. Some conservation biologists and conservationists have used genetic pollution for a number of years as a term to describe gene flow from a non-native , invasive subspecies , domestic , or genetically-engineered population to a wild indigenous population. The introduction of genetic material into

6489-429: The escape of transgenes. Physical containment includes barriers such as filters in labs, screens in greenhouses, and isolation distances in the field. Isolation distances have not always been successful, such as transgene escape from an isolated field into the wild in herbicide-resistant bentgrass Agrostis stolonifera . Another suggested method that applies specifically to protection traits (e.g. pathogen resistance)

6592-436: The extinction of many indigenous waterfowl. The mallard itself is the ancestor of most domestic ducks, and its naturally evolved wild gene pool gets genetically polluted in turn by the domestic and feral populations. Over time, a continuum of hybrids ranging between almost typical examples of either species develop; the speciation process is beginning to reverse itself. This has created conservation concerns for relatives of

6695-463: The extinction of many indigenous waterfowl. This species is the main ancestor of most breeds of domestic duck , and its naturally evolved wild gene pool has been genetically polluted by the domestic and feral mallard populations. The mallard was one of the many bird species originally described in the 1758 10th   edition of Systema Naturae by Carl Linnaeus . He gave it two binomial names : Anas platyrhynchos and Anas boschas . The latter

6798-550: The eye stripes of mallard females. Drakes are also similar to a heavily frosted Mallard with a yellow/green bill and orange legs and feet. There is also a color variation known as "golden", popular in the UK, which replaces the black feather pigments with a light golden brown color. Welsh Harlequins have a unique, natural sex-linked characteristic. As day olds, sex can be determined based on bill colour with over 90% accuracy. Young drakes will have darker bills while female with have lighter with

6901-423: The female. Lebret (1961) calls this behaviour "Attempted Rape Flight", and Stanley Cramp and K.E.L. Simmons (1977) speak of "rape-intent flights". Male mallards also occasionally chase other male ducks of a different species, and even each other, in the same way. In one documented case of "homosexual necrophilia", a male mallard copulated with another male he was chasing after the chased male died upon flying into

7004-458: The fitness of a population. It is called genetic pollution when it negatively impacts the fitness of a population, such as through outbreeding depression and the introduction of unwanted phenotypes which can lead to extinction. Conservation biologists and conservationists have used the term to describe gene flow from domestic, feral, and non-native species into wild indigenous species , which they consider undesirable. They promote awareness of

7107-414: The fledgling period has ended, and the duckling is now a juvenile. The duckling is able to fly 50–60 days after hatching. Its bill soon loses its dark grey colouring, and its sex can finally be distinguished visually by three factors: 1)   the bill is yellow in males, but black and orange in females; 2)   the breast feathers are reddish-brown in males, but brown in females; and 3)   in males,

7210-408: The flock to begin fighting. It is possible that this behaviour allows the female to evaluate the strength of potential partners. The drakes that end up being left out after the others have paired off with mating partners sometimes target an isolated female duck, even one of a different species, and proceed to chase and peck at her until she weakens, at which point the males take turns copulating with

7313-535: The gene pool of a population by human intervention can have both positive and negative effects on populations. When genetic material is intentionally introduced to increase the fitness of a population, this is called genetic rescue . When genetic material is unintentionally introduced to a population, this is called genetic pollution and can negatively affect the fitness of a population (primarily through outbreeding depression ), introduce other unwanted phenotypes, or theoretically lead to extinction. An introduced species

7416-402: The genes of the domestic duck. While the keeping of domestic breeds is more popular, pure-bred mallards are sometimes kept for eggs and meat, although they may require wing clipping to restrict flying. Mallards are one of the most common species shot in waterfowl hunting due to their large population size. The ideal location for hunting mallards is considered to be where the water level

7519-563: The genetic pool (a process called genetic pollution ), which is an irreversible change." Invasive species can invade both large and small native populations and have a profound effect. Upon invasion, invasive species interbreed with native species to form sterile or more evolutionarily fit hybrids that can outcompete the native populations. Invasive species can cause extinctions of small populations on islands that are particularly vulnerable due to their smaller amounts of genetic diversity. In these populations, local adaptations can be disrupted by

7622-420: The host mallard, but the hen may attempt to eject them or even abandon the nest if parasitism occurs during egg laying. In addition to human hunting, mallards of all ages (but especially young ones) and in all locations must contend with a wide diversity of predators including raptors and owls , mustelids , corvids , snakes , raccoons , opossums , skunks , turtles , large fish , felids , and canids ,

7725-471: The ibex in Turkey and Sinai were locally adapted to their environments so when placed in a new environmental context did not flourish. Additionally, the environmental toll that may arise from the introduction of a new species may be so disruptive that the ecosystem is no longer able to sustain certain populations. The use of the word "pollution" in the term genetic pollution has a deliberate negative connotation and

7828-409: The impacts of genetic mixing. Mutations within organisms can be executed through the process of exposing the organism to chemicals or radiation in order to generate mutations. This has been done in plants in order to create mutants that have a desired trait. These mutants can then be bred with other mutants or individuals that are not mutated in order to maintain the mutant trait. However, similar to

7931-576: The introduction of new genes that may not be as suitable for the small island environments. For example, the Cercocarpus traskiae of the Catalina Island off the coast of California has faced near extinction with only a single population remaining due to the hybridization of its offspring with Cercocarpus betuloides . Increased contact between wild and domesticated populations of organisms can lead to reproductive interactions that are detrimental to

8034-503: The island of Niue , an atypical location for mallards. The mallard inhabits a wide range of habitats and climates, from the Arctic tundra to subtropical regions. It is found in both fresh- and salt-water wetlands, including parks, small ponds, rivers, lakes and estuaries , as well as shallow inlets and open sea within sight of the coastline. Water depths of less than 0.9 metres (3.0 ft) are preferred, with birds avoiding areas more than

8137-472: The last two including domestic cats and dogs. The most prolific natural predators of adult mallards are red foxes ( Vulpes vulpes ; which most often pick off brooding females) and the faster or larger birds of prey, (e.g. peregrine falcons , Aquila or Haliaeetus eagles). In North America, adult mallards face no fewer than 15 species of birds of prey, from northern harriers ( Circus hudsonius ) and short-eared owls ( Asio flammeus ) (both smaller than

8240-734: The main conservation risk they pose comes from the loss of genetic diversity among a region's traditional ducks once humans and mallards colonise an area. Mallards are very adaptable, being able to live and even thrive in urban areas which may have supported more localised, sensitive species of waterfowl before development. The release of feral mallards in areas where they are not native sometimes creates problems through interbreeding with indigenous waterfowl . These non-migratory mallards interbreed with indigenous wild ducks from local populations of closely related species through genetic pollution by producing fertile offspring. Complete hybridisation of various species of wild duck gene pools could result in

8343-447: The male is black, with white-bordered dark tail feathers. The bill of the male is a yellowish-orange tipped with black, with that of the female generally darker and ranging from black to mottled orange and brown. The female mallard is predominantly mottled, with each individual feather showing sharp contrast from buff to very dark brown, a coloration shared by most female dabbling ducks, and has buff cheeks, eyebrow, throat, and neck, with

8446-488: The mallard species. Ecological changes and hunting have also led to a decline of local species; for example, the New Zealand grey duck population declined drastically due to overhunting in the mid-20th century. Hybrid offspring of Hawaiian ducks seem to be less well adapted to native habitat, and using them in re-introduction projects apparently reduces success. In summary, the problems of mallards "hybridising away" relatives

8549-539: The mallard, such as the Hawaiian duck , the New Zealand grey duck ( A.   s. superciliosa) subspecies of the Pacific black duck , the American black duck, the mottled duck , Meller's duck , the yellow-billed duck , and the Mexican duck , in the latter case even leading to a dispute as to whether these birds should be considered a species (and thus entitled to more conservation research and funding) or included in

8652-474: The moulting period, which begins in June (in the Northern Hemisphere). During the brief time before this, however, the males are still sexually potent and some of them either remain on standby to sire replacement clutches (for female mallards that have lost or abandoned their previous clutch) or forcibly mate with females that appear to be isolated or unattached regardless of their species and whether or not they have

8755-444: The nesting season has been found to be longer, eggs and clutches are larger and nest survival is generally greater compared with mallards in their native range. In cases where a nest or brood fails, some mallards may mate for a second time in an attempt to raise a second clutch, typically around early-to-mid summer. In addition, mallards may occasionally breed during the autumn in cases of unseasonably warm weather; one such instance of

8858-479: The nuclear genome displays a notable lack of genetic structure. Haplotypes typical of American mallard relatives and eastern spot-billed ducks can be found in mallards around the Bering Sea . The Aleutian Islands hold a population of mallards that appear to be evolving towards becoming a subspecies , as gene flow with other populations is very limited. Also, the paucity of morphological differences between

8961-503: The other half sleeps, was first demonstrated in mallards, although it is believed to be widespread among birds in general. Since 1998, the mallard has been rated as a species of least concern on the IUCN Red List of Endangered Species . This is because it has a large range–more than 20,000,000 km (7,700,000 mi ) and because its population is increasing, rather than declining by 30% over ten years or three generations and thus

9064-548: The past, the newly worrisome element, in Dr. Boitani's opinion, is the increasing disparity in numbers, which suggests that interbreeding will become fairly common. As a result, 'genetic pollution of the wolf gene pool might reach irreversible levels', he warned. 'By hybridization, dogs can easily absorb the wolf genes and destroy the wolf, as it is,' he said. The wolf might survive as a more doglike animal, better adapted to living close to people, he said, but it would not be 'what we today call

9167-525: The point of visiting water features in human courtyards . Mallards have had a long relationship with humans. Almost all domestic duck breeds derive from the mallard, with the exception of a few Muscovy breeds, and are listed under the trinomial name A. p. domesticus . Mallards are generally monogamous while domestic ducks are mostly polygamous . Domestic ducks have no territorial behaviour and are less aggressive than mallards. Domestic ducks are mostly kept for meat; their eggs are also eaten, and have

9270-653: The purpose of property protection, but could be beneficial in preventing the dispersal of transgenes. GeneSafe technologies introduced a method that became known as "Terminator." This method is based on seeds that produce sterile plants. This would prevent movement of transgenes into wild populations as hybridization would not be possible. However, this technology has never been deployed as it disproportionately negatively affects farmers in developing countries, who save seeds to use each year (whereas in developed countries, farmers generally buy seeds from seed production companies). Physical containment has also been utilized to prevent

9373-505: The result of pollen traveling from farmed crops to neighboring wild plants of the same species. For farmed animals, this reproduction may happen as the result of escaped or released animals. A popular example of this phenomenon is the gene flow between wolves and domesticated dogs. The New York Times cites, from the words of biologist Luigi Boitani, "Although wolves and dogs have always lived in close contact in Italy and have presumably mated in

9476-495: The risks associated with introducing individuals to a certain environment, the variation created by mutated individuals could have a negative impact on native populations as well. Since 2005 there has existed a GM Contamination Register , launched for GeneWatch UK and Greenpeace International that records all incidents of intentional or accidental release of organisms genetically modified using modern techniques. Genetic use restriction technologies (GURTs) were developed for

9579-470: The risks of genetic pollution associated with organisms that have been genetically engineered: Not only are there risks in terms of genetic engineering, but there are risks that emerge from species hybridization. In Czechoslovakia, ibex were introduced from Turkey and Sinai to help promote the ibex population there, which caused hybrids that produced offspring too early, which caused the overall population to disappear completely. The genes of each population of

9682-406: The speculum. In captivity, domestic ducks come in wild-type plumages, white, and other colours. Most of these colour variants are also known in domestic mallards not bred as livestock, but kept as pets, aviary birds, etc., where they are rare but increasing in availability. A noisy species, the female has the deep quack stereotypically associated with ducks. The female will often call with

9785-499: The system. Introduced species are not always disruptive to an environment, however. Tomás Carlo and Jason Gleditch of Penn State University found that the number of "invasive" honeysuckle plants in the area correlated with the number and diversity of the birds in the Happy Valley Region of Pennsylvania, suggesting introduced honeysuckle plants and birds formed a mutually beneficial relationship. Presence of introduced honeysuckle

9888-517: The transgene. Not all genetically engineered organisms cause genetic pollution. Genetic engineering has a variety of uses and is specifically defined as a direct manipulation of the genome of an organism. Genetic pollution can occur in response to the introduction of a species that is not native to a particular environment, and genetically engineered organisms are examples of individuals that could cause genetic pollution following introduction. Due to these risks, studies have been done in order to assess

9991-625: The unintentional process of (modernly) genetically modified organisms (GMOs) dispersing their genes into the natural environment by breeding with wild plants or animals. Concerns about negative consequences from gene flow between genetically engineered organisms and wild populations are valid. Most corn and soybean crops grown in the midwestern USA are genetically modified. There are corn and soybean varieties that are resistant to herbicides like glyphosate and corn that produces neonicotinoid pesticide within all of its tissues. These genetic modifications are meant to increase yields of crops but there

10094-440: The wild population experiences a decreased likelihood of survival after reproducing with domesticated populations of salmon. The Washington Department of Fish and Wildlife cites that "commonly expressed concerns surrounding escaped Atlantic salmon include competition with native salmon, predation, disease transfer, hybridization, and colonization." A report done by that organization in 1999 did not find that escaped salmon posed

10197-415: The wild population's ability to survive. A wild population is one that lives in natural areas and is not regularly looked after by humans. This contrasts with domesticated populations that live in human controlled areas and are regularly, and historically, in contact with humans. Genes from domesticated populations are added to wild populations as a result of reproduction. In many crop populations this can be

10300-482: The winter. The mallard usually feeds by dabbling for plant food or grazing; there are reports of it eating frogs , other amphibians , and fish , including carcasses . However, in 2017 a flock of mallards in Romania were observed hunting small migratory birds, including grey wagtails and black redstarts , the first documented occasion they had been seen attacking and consuming large vertebrates. It usually nests on

10403-430: Was also popularized by environmentalist Jeremy Rifkin in his 1998 book The Biotech Century . While intentional crossbreeding between two genetically distinct varieties is described as hybridization with the subsequent introgression of genes, Rifkin, who had played a leading role in the ethical debate for over a decade before, used genetic pollution to describe what he considered to be problems that might occur due to

10506-450: Was associated with higher diversity of the bird populations in that area, demonstrating that introduced species are not always detrimental to a given environment and it is completely context dependent. Conservation biologists and conservationists have, for a number of years, used the term to describe gene flow from domestic, feral, and non-native species into wild indigenous species , which they consider undesirable. For example, TRAFFIC

10609-519: Was generally preferred until 1906 when Einar Lönnberg established that A.   platyrhynchos had priority, as it appeared on an earlier page in the text. The scientific name comes from Latin Anas , "duck" and Ancient Greek πλατυρυγχος, platyrhynchus , "broad-billed" (from πλατύς, platys , "broad" and ρυγχός, rhunkhos , "bill"). The genome of Anas platyrhynchos was sequenced in 2013. The name mallard originally referred to any wild drake, and it

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