This article may lend undue weight to the Florida Duck (A. f. fulvigula) versus other populations (A. f. macularius).(August 2016) |
Mottled duck | |
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A pair of mottled ducks (male on left, female on right) at Everglades National Park, Florida, US | |
Scientific classification | |
Domain: | Eukaryota |
Kingdom: | Animalia |
Phylum: | Chordata |
Class: | Aves |
Order: | Anseriformes |
Family: | Anatidae |
Genus: | Anas |
Species: | A. fulvigula |
Binomial name | |
Anas fulvigula Ridgway, 1874 | |
Subspecies | |
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The mottled duck (Anas fulvigula) [note 1] 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.
Along the Gulf of Mexico coast, the mottled duck is one of the most frequently banded waterfowl. This is due in part to the fact that it is mostly non-migratory. [3] Approximately one out of every 20 mottled ducks is banded, making it an extremely prized and sought after bird among hunters.
There are two distinct subspecies of the mottled duck. One subspecies, the Gulf Coast mottled duck (A. f. maculosa), lives on the Gulf of Mexico coast between Alabama and Tamaulipas (Mexico); outside the breeding season, individual birds may venture as far south as Veracruz. The other, the Florida mottled duck (A. f. fulvigula), is resident in central and southern Florida and occasionally strays north to Georgia. The same disjunct distribution pattern was also historically found in the local sandhill cranes. Individuals of both subspecies were introduced into South Carolina in the 1970s and 1980s, where the birds of mixed ancestry have greatly expanded in range, extending through the Atlantic coastal plain of Georgia into northeastern Florida. [4] [5]
The adult mottled duck is 44 to 61 cm (17–24 in) long from head to tail. It has a dark body, lighter head and neck, orange legs and dark eyes. Both sexes have a shiny green-blue speculum (wing patch), which is not bordered with white as with the mallard. Males and females are similar, but the male's bill is bright yellow, whereas the female's is deep to pale orange, occasionally lined with black splotches around the edges and near the base.
The plumage is darker than in female mallards, especially at the tail, and the bill is yellower. In flight, the lack of a white border to the speculum is a key difference. The American black duck is darker than most mottled ducks, and its wing-patch is more purple than blue. The behaviour and voice are the same as the mallard.
Mottled ducks feed by dabbling in shallow water, and grazing on land. They mainly eat plants, but also some mollusks and aquatic insects. The ducks are fairly common within their restricted range; they are resident all-year round and do not migrate. Their breeding habitat is brackish and intermediate coastal marshes, but they will also use human developed habitat such as retaining ponds, water impoundments, and agricultural land during the breeding season. [3] According to a review of their breeding behaviors, mottled duck nests may be found in "pastures, levees, dry cordgrass marsh, cutgrass marsh, spoil banks, and small islands." [3]
Measurements: [6]
The Floridian population, which occurs approximately south of Tampa, is separated as the nominate subspecies Anas fulvigula fulvigula and is occasionally called the Florida mottled duck or Florida mallard. It differs from the other subspecies, the Gulf Coast mottled duck (A. f. maculosa) (etymology: maculosa, Latin for "the mottled one"), by being somewhat lighter in color and less heavily marked; while both subspecies are intermediate between female mallards and American black ducks, the Florida mottled duck is closer to the former and the Gulf Coast mottled duck closer to the latter in appearance; this is mainly recognizable in the lighter head being quite clearly separated from the darker breast in Gulf Coast mottled ducks, but much less so in Florida mottled ducks. As the subspecies' ranges do not overlap, these birds can only be confused with female mallards and American black ducks however; particularly female American black ducks are often only reliably separable by their dark purple speculum from mottled ducks in the field.
mtDNA control region sequence data indicates that these birds are derived from ancestral American black ducks, being far more distantly related to the mallard, and that the two subspecies, as a consequence of their rather limited range and sedentary habits, are genetically well distinct already. [7]
As in all members of the "mallardine" clade of ducks, they are able to produce fertile hybrids with their close relatives, the American black duck and the mallard. This has always been so to a limited extent; individuals of the migratory American black ducks which winter in the mottled duck's range may occasionally stay there and mate with the resident species, and for the mallard, which colonized North America later, the same holds true. [7] Genetic tools have been developed in order to robustly classify hybrids and to assess and monitor the genetic dynamics of introgression between the Florida mottled duck and the mallard. [8]
While the resultant gene flow is no cause for immediate concern, [note 2] habitat destruction and excessive hunting could eventually reduce this species to the point where the hybridization with mallards would threaten to make it disappear as a distinct taxon. [9] This especially applies to the Florida mottled duck, [10] in the fairly small range of which rampant habitat destruction due to urbanization and draining of wetlands has taken place in the last decades; this, in combination with climate change affecting the Everglades, could be sufficient to cause the Florida mottled duck to decline to a point where hunting would have to be restricted or prohibited. [7] At present, these birds too appear to be holding their own, with a population of 50,000-70,000 individuals. While hybridization is common, double white bars above and below the speculum are not a sufficient indicator of hybridization and therefore should not be used to determine genetics. [1]
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 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 redhead is a medium-sized diving duck. The scientific name is derived from Greek aithuia, an unidentified seabird mentioned by authors including Hesychius and Aristotle, and Latin americana, of America. The redhead is 37 cm (15 in) long with an 84 cm (33 in) wingspan. Redhead weight ranges from 2.0 to 2.5 lbs, with males weighing an average of 2.4 lbs and females weighing an average of 2.1 lbs. It belongs to the genus Aythya, together with 11 other described species. The redhead and the common pochard form a sister group which together is sister to the canvasback.
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 blue-winged teal is a species of bird in the duck, goose, and swan family Anatidae. One of the smaller members of the dabbling duck group, it occurs in North America, where it breeds from southern Alaska to Nova Scotia, and south to northern Texas. It winters along the Pacific and Atlantic coasts and south into the Caribbean islands and Central America.
The Muscovy duck is a duck native to the Americas, from the Rio Grande Valley of Texas and Mexico south to Argentina and Uruguay. Feral Muscovy ducks are found in New Zealand, Australia, and in Central and Eastern Europe. Small wild and feral breeding populations have also established themselves in the United States, particularly in Florida, Louisiana, Massachusetts, the Big Island of Hawaii, as well as in many other parts of North America, including southern Canada.
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 fulvous whistling duck or fulvous tree duck is a species of whistling duck that breeds across the world's tropical regions in much of Mexico and South America, the West Indies, the southern United States, sub-Saharan Africa and the Indian subcontinent. It has plumage that is mainly reddish brown, long legs and a long grey bill, and shows a distinctive white band across its black tail in flight. Like other members of its ancient lineage, it has a whistling call which is given in flight or on the ground. Its preferred habitat consists of wetlands with plentiful vegetation, including shallow lakes and paddy fields. The nest, built from plant material and unlined, is placed among dense vegetation or in a tree hole. The typical clutch is around ten whitish eggs. The breeding adults, which pair for life, take turns to incubate, and the eggs hatch in 24–29 days. The downy grey ducklings leave the nest within a day or so of hatching, but the parents continue to protect them until they fledge around nine weeks later.
The Pacific black duck is a dabbling duck found in much of Indonesia, New Guinea, Australia, New Zealand, and many islands in the southwestern Pacific, reaching to the Caroline Islands in the north and French Polynesia in the east. It is usually called the grey duck in New Zealand, where it is also known by its Maori name, pārera.
The Mariana mallard or Oustalet's duck is an extinct species of duck of the genus Anas that was endemic to the Mariana Islands. Its taxonomic status is debated, and it has variously been treated as a full species, a subspecies of the mallard or of the Pacific black duck, or sometimes as a subspecies of the Indian spot-billed duck.
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 Patagonian crested duck, also known as the southern crested duck, or the grey duck in the Falkland Islands, is the nominate of two subspecies of the crested duck.
The eastern spot-billed duck or Chinese spot-billed duck is a species of dabbling duck that breeds in East and Southeast Asia. This species was formerly considered a subspecies of the Indian spot-billed duck and both were referred to as the spot-billed duck. The name is derived from the yellow spot on the bill.