| Falcated duck | |
|---|---|
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| Male above, female below | |
Scientific classification  | |
| Domain: | Eukaryota |
| Kingdom: | Animalia |
| Phylum: | Chordata |
| Class: | Aves |
| Order: | Anseriformes |
| Family: | Anatidae |
| Genus: | Mareca |
| Species: | M. falcata |
| Binomial name | |
| Mareca falcata (Georgi, 1775) | |
| Synonyms | |
Anas falcataGeorgi, 1775 | |
The falcated duck or falcated teal (Mareca falcata) is a gadwall-sized dabbling duck from the east Palearctic (East Siberia and Mongolia to North Japan; wintering to India).
The closest relative of this species is the gadwall, followed by the wigeons. [2] The species was assigned to the proposed genus Mareca after its previous placement in the genus Anas was found to be paraphyletic in 2009.
There are many species that have mitochondrial DNA lineages that are phylogenetically intermixed with other species, but studies have rarely tested the cause of such paraphyly. In a study that was conducted, there were tested two hypotheses that could explain mitochondrial paraphyly of Holarctic gadwalls (Anas strepera) with respect to Asian falcated ducks (A. falcata). First, hybridization could have resulted in falcated duck mitochondrial DNA (mtDNA) introgressing into the gadwall gene pool. Second, gadwalls and falcated ducks could have diverged so recently that mtDNA lineages have not sorted to reciprocal monophyly. They[ who? ] used coalescent analyses of three independent loci to distinguish between these two hypotheses. Two lines of evidence support introgression. First, analyses of the three loci combined show that some introgression is necessary to explain current genetic diversity in gadwalls. Second, they generated alternative predictions regarding time since divergence estimated from mtDNA: falcated ducks and gadwalls would have diverged between 65,000 and 700,000 years before present (ybp) under the introgression hypothesis and between 11,000 and 76,000 ybp under the incomplete lineage sorting hypothesis. The two independent nuclear introns indicated that these species diverged between 210,000 and 5,200,000 ybp, which did not overlap the predicted time for incomplete lineage sorting. These analyses also suggested that ancient introgression (similar to 14,000 ybp) has resulted in the widespread distribution and high frequency of falcated-like mtDNA (5.5% of haplotypes) in North America. This is the first study to use a rigorous quantitative framework to reject incomplete lineage sorting as the cause of mitochondrial paraphyly. [3]
The falcated duck breeds in eastern Asia. It nests in eastern Russia, in Khabarovsk, Primorskiy, Amur, Chita, Buryatia, Irkutsk, Tuva, eastern Krasnoyarsk, south central Sakha, Sakhalin, extreme northeastern North Korea and northern China, in northeastern Inner Mongolia, and northern Heilongjiang, and in northern Japan, Hokkaidō, Aomori, and the Kuril Islands. [4] It is widely recorded well outside its normal range, but the popularity of this beautiful duck in captivity clouds the origins of these extralimital birds.
This dabbling duck is strongly migratory and winters in much of Southeast Asia. In India: Uttar Pradesh, Bihār, Assam, eastern Haryāna. Also in northern Bangladesh, northern and central Myanmar, northern Laos to the Mekong River, northern Vietnam (from about Hanoi north), and China: Hainan, Taiwan, Yunnan, Guangxi, Guangdong, Fujian, Jiangxi, northern Hunan, Hubei, Zhejiang, Anhui, Jiangsu, Shandong, southern Hebei, Shanxi, northern Shaanxi. [4] It is gregarious outside the breeding season and will then form large flocks.
It is estimated that there are about 89,000 falcated ducks in total; this is much higher than the previous population estimate of 35,000 worldwide. [5]
During a survey done in Central China, a migratory area in the winter for the falcated duck, the numbers of animals sighted was minimal. In 2004 only 4 were recorded, and in 2005 only 10. [6]
This is a species of lowland wetlands, such as water meadows or lakes, and usually feeds by dabbling for plant food or grazing.
The National Nature Reserves supported high proportions of eastern China's populations of globally threatened Anatidae species (IUCN, 2009): 30% of the near threatened falcated duck (Anas falcata) populations. There is about twenty-seven percent of falcated duck species existing in the National Nature Reserves. [7]
The falcated duck has a large range, with an estimated global extent of occurrence of 1,000,000–10,000,000 km2 (390,000–3,860,000 sq mi). [1]
The breeding range of the falcated duck is from eastern Siberia and Mongolia to northeastern China and northern Japan with wintering grounds in the northern part of southeast Asia to northeastern India. There have also been a small number of sightings of falcated ducks in western North America and Poland. However, these sightings have been attributed to vagrants and ducks that have escaped from captivity. [8]
Males and females have similar lengths at 46 to 53 cm (18–21 in). Their weight can range from 422 to 770 g (14.9–27.2 oz), with males weighing more than their female counterparts. Wingspans range from 79 to 91 cm (31–36 in). [9] The breeding male is unmistakable. Most of the body plumage is finely vermiculated grey, with the long sickle-shaped tertials, which give this species its name, hanging off its back. The large head is dark green with a white throat, and a dark green collar and bronzed crown. [10] The vent region is patterned in yellow, black and white.
The female falcated duck is dark brown, with plumage much like a female wigeon. Its long grey bill is an aid to identification. [10] The eclipse male is like the female, but darker on the back and head. In flight both sexes show a pale grey underwing. The blackish speculum is bordered with a white bar on its inner edge. [10] Young birds are buffer than the female and have short tertials.
Juveniles have plumage similar to females of the species. [11]
These ducks are usually quiet except on breeding territory. The male duck has a shrill whistle tyu-tyu-vit…tyu-vit…tyu-tyu-vit (Dementiev and Gladkov 1952) and a quiet whistle ending with a wavering uit-trr (Flint et al. 1984). The female duck has a hoarse, quack, short two-syllable inciting call, and a high pitched, two to four syllable Decrescendo call (Lorenz and Von de Wall 1960). [12]
Falcated ducks have food habits generally consisting of small invertebrate and other insects as well as plant foods. They mainly eat vegetation or insects near to the water, consuming animals such as larvae, crustaceans, and mollusks. They likewise eat plant foods: leaves as well as seeds, grains, and nuts. Many assume that the falcated duck helps disperse seeds over large areas because of their diet. These ducks are primarily herbivorous. These ducks are hosts to a number of different parasites (ticks, fleas, lice) and thus carry diseases such as: the West Nile virus, avian influenza, avian pox, salmonellosis, staphylococcosis, and E. coli . Moreover, they carry viruses, bacteria, fungi and protozoans that can be transferred to other creatures, for instance vertebrates and even humans. [9]
The clutch is 6–10 eggs. Eggs are generally laid in late May. They have their nests on the ground in thick grasses, tussocks, swamped shrubbery, or hidden in deadwood. Usually the eggs are nested near water but have also been seen in small bushes approximately 80 m (260 ft) from the water. The eggs have a color of white with a pinkish yellow tint. Females incubate the eggs alone, 24–25 days in captivity. The males will leave the female during incubation. [12]
Falcated ducks have a very intricate courtship ritual. Females perform a series of inciting calls and other movements while preening behind the wings of their targeted male. Males use a courting method similar to others in the Anas genus, including an introductory shake, a neck-stretching burp call, a grunt whistle, and a head-up-tail-up display. During the mating season the falcated ducks form monogamous pairs that last throughout the mating season. [9] It is not known how long the falcated duck lifespan is. There is also not much information on their territory size because these ducks are not studied as closely as other more popular species like swans or geese. [9]
A fieldwork study at Hyo-ko Waterfowl Park, a nature preserve in Niigata, Japan, found what they presumed was a male hybrid of a falcated duck and a Eurasian wigeon. They have found these “wild” hybrids in several instances over the past few years. These birds shared morphological traits with both species. Still, most of the traits favored the falcated duck. It was reported that these hybrid birds have joined courting parties of Eurasian wigeon and even attempted to compete with wigeon males. Grunt-whistling, and burping calls being the method of inciting courtship, even resemble that of the falcated duck and not of the Eurasian wigeon. The hybrid bird most be closely watched, was quite sexually active, however, it is not yet known if they can reproduce with either of the female species. [13]
Hybridization between two different species often leaves the offspring sterile, but this genus shows a surprising amount of hybrid fertility. This hybrid species performed courtship rituals more closely related to the falcated duck, yet socially was active in Eurasian wigeon flocks. Successful reproduction was not seen between the hybrid species and a pure Eurasian wigeon female during the fieldwork study. Further study of hybrid avian species can help shed light onto avian reproduction and their evolutionary biology. [13]
A primary threat to the falcated duck is hunting, as people want them for food and their feathers. Their habitat loss is also caused by the drainage of the wetlands. [12] Although the overall population of the falcated duck is larger than once believed and is no longer classified as an endangered species, it is still considered "near threatened" on the IUCN's (or the International Union for the Conservation of Nature's) Animal Red List. [14]
The falcated duck requires coastal wetlands for its survival. One of the most ecologically sensitive areas in the world is the eastern end of Nanhui county, China, and is a site for the falcated duck during the migratory season. This area is crucial for the falcated duck due to its population being extremely low. Urbanization and economic growth of this area has led to a significant environmental disturbance in this area. A reclamation project to create artificial wetlands was started in 1999 and finished in 2005. Studies have been done to see if the artificial wetlands were as efficient as the natural ones, and although the artificial wetlands did see migratory shorebirds present, their population was not as high as the natural wetlands. Much more research needs to be done before the artificial wetlands can match the natural wetlands, and provide an acceptable habitat for the falcated duck.
Around the time of the harvesting seasons during the Chinese spring festival of winter in Nanhui County of Shanghai, China, the pond managers drain the water in the pond in order to catch fish for commercial purposes. Around that time, the pond was dominated by falcated ducks roosting there. After the pond is drained it remains dry until the following spring when water is replenished for fresh cultivation. The time that the water is replenished is very critical for migrant waterbirds in the spring. If the water is replenished too late then the dry pond is inapt for shorebirds and herons.
The falcated duck is currently in a state of near threatened on the IUCN's Red List. [1] They are protected under the Migratory Bird Treaty Act, and their overall population seems to be (for the most part) stable and growing. [9] Falcated duck populations are present in a number of wildlife preservers, national parks and other protected areas, [14] and zoos.
There are several proposed plans of action in protecting the falcated duck. Conservationists are keen to continue monitoring populations that have unfortunately stopped breeding, and plan to petition for hunting and shooting regulations on both the local and national level, respectively. Conservationists are also aware as to the great lack of education in regards to waterfowl extinction. For hunters who make a living off of either using the falcated duck as a food source or from simple sport hunts, conservationists are looking for alternative employment opportunities. Finally, conservationists hope to improve the management and coordination of already existing nature reserves where the falcated duck is present. [14] [15]
The pintail or northern pintail is a duck species with wide geographic distribution that breeds in the northern areas of Europe and across the Palearctic and North America. It is migratory and winters south of its breeding range to the equator. Unusually for a bird with such a large range, it has no geographical subspecies if the possibly conspecific duck Eaton's pintail is considered to be a separate species.
The northern shoveler, known simply in Britain as the shoveler, is a common and widespread duck. It breeds in northern areas of Europe and across the Palearctic and across most of North America, wintering in southern Europe, the Indian subcontinent, Southeast Asia, Central America, the Caribbean, and northern South America. It is a rare vagrant to Australia. In North America, it breeds along the southern edge of Hudson Bay and west of this body of water, and as far south as the Great Lakes west to Colorado, Nevada, and Oregon.
The gadwall is a common and widespread dabbling duck in the family Anatidae.
The Eurasian wigeon or European wigeon, also known as the widgeon or the wigeon, is one of three species of wigeon in the dabbling duck genus Mareca. It is common and widespread within its Palearctic range.
The American wigeon, also known as the baldpate, is a species of dabbling duck found in North America. Formerly assigned to Anas, this species is classified with the other wigeons in the dabbling duck genus Mareca. It is the New World counterpart of the Eurasian wigeon.
The mallard or wild duck 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 have green heads, while the females have mainly brown-speckled plumage. Both sexes have an area of white-bordered black or iridescent purple or blue feathers called 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 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 Eurasian teal, common teal, or Eurasian green-winged teal is a common and widespread duck that breeds in temperate Eurosiberia and migrates south in winter. The Eurasian teal is often called simply the teal due to being the only one of these small dabbling ducks in much of its range. The bird gives its name to the blue-green colour teal.
The American teal or green-winged teal is a common and widespread duck that breeds in the northern areas of North America except on the Aleutian Islands. It was considered conspecific with the Eurasian teal for some time, but has since been split into its own species. The American Ornithological Society continues to debate this determination; however, nearly all other authorities consider it distinct based on behavioral, morphological, and molecular evidence. The scientific name is from Latin Anas, "duck" and carolinensis, "of Carolina".
The American black duck is a large dabbling duck in the family Anatidae. It was described by William Brewster in 1902. It is the heaviest species in the genus Anas, weighing 720–1,640 g (1.59–3.62 lb) on average and measuring 54–59 cm (21–23 in) in length with an 88–95 cm (35–37 in) wingspan. It somewhat resembles the female and eclipse male mallard in coloration, but has a darker plumage. The male and female are generally similar in appearance, but the male's bill is yellow while the female's is dull green with dark marks on the upper mandible. It is native to eastern North America. During the breeding season, it is usually found in coastal and freshwater wetlands from Saskatchewan to the Atlantic in Canada and the Great Lakes and the Adirondacks in the United States. It is a partially migratory species, mostly wintering in the east-central United States, especially in coastal areas.
The Cape teal also Cape wigeon or Cape widgeon is a 44–46 cm long dabbling duck of open wetlands in sub-Saharan Africa.
The yellow-billed duck is a 51–58 cm long dabbling duck which is an abundant resident breeder in southern and eastern Africa. This duck is not migratory, but wanders in the dry season to find suitable waters. It is highly gregarious outside the breeding season and forms large flocks.
The Indian spot-billed duck is a species of large dabbling duck that is a non-migratory breeding duck throughout freshwater wetlands in the Indian subcontinent. The name is derived from the red spot at the base of the bill that is found in the mainland Indian population. When in water it can be recognized from a long distance by the white tertials that form a stripe on the side, and in flight it is distinguished by the green speculum with a broad white band at the base. This species and the eastern spot-billed duck were formerly considered conspecific, together called the spot-billed duck.
The knob-billed duck or African comb duck is a type of duck found along the tropical/sub-tropical wetlands and waterways of Sub-Saharan Africa and the island of Madagascar, as well as most of South Asia and mainland Indochina.
Anas is a genus of dabbling ducks. It includes the pintails, most teals, and the mallard and its close relatives. It formerly included additional species but following the publication of a molecular phylogenetic study in 2009 the genus was split into four separate genera. The genus now contains 31 living species. The name Anas is the Latin for "duck".
The mottled duck or mottled mallard is a medium-sized species of dabbling duck. It is intermediate in appearance between the female mallard and the American black duck. It is closely related to those species, and is sometimes erroneously considered a subspecies of the former.
The blue-billed teal, spotted teal or Hottentot teal is a species of dabbling duck of the genus Spatula. It is migratory resident in eastern and southern Africa, from Sudan and Ethiopia west to Niger and Nigeria and south to South Africa and Namibia. In west Africa and Madagascar it is sedentary.
The Chiloé wigeon, also known as the southern wigeon, is one of three extant species of wigeon in the genus Mareca of the dabbling duck subfamily. This bird is indigenous to the southern part of South America, including the Chiloé Archipelago. In its native range, it is called the pato overo or pato real, although the latter name also refers to the Muscovy in the wild. Its specific epithet, sibilatrix, means 'whistler', referring to the bird's.Its name comes from its residence,the Chloe Archipelago
The Hawaiian duck or koloa is a species of bird in the family Anatidae that is endemic to the large islands of Hawaiʻi. Taxonomically, the koloa is closely allied with the mallard. It differs in that it is monochromatic and non-migratory. As with many duck species in the genus Anas, Hawaiian duck and mallards can interbreed and produce viable offspring, and the koloa has previously been considered an island subspecies of the mallard. However, all major authorities now consider this form to be a distinct species within the mallard complex. Recent analyses indicate that this is a distinct species that arose through ancient hybridization between mallard and the Laysan duck. The native Hawaiian name for this duck is koloa maoli, or simply koloa. This species is listed as endangered by the IUCN Red List of Threatened Species, and its population trend is decreasing.
The Mexican duck is a species of dabbling duck that breeds in Mexico and the southwestern United States.
The wigeons or widgeons are a group of birds, dabbling ducks currently classified in the genus Mareca along with two other species. There are three extant species of wigeon, in addition to one recently extinct species.
