Hooded merganser | |
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Male | |
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Female | |
Scientific classification ![]() | |
Domain: | Eukaryota |
Kingdom: | Animalia |
Phylum: | Chordata |
Class: | Aves |
Order: | Anseriformes |
Family: | Anatidae |
Genus: | Lophodytes Reichenbach, 1853 |
Species: | L. cucullatus |
Binomial name | |
Lophodytes cucullatus | |
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Breeding Migration Year-round Nonbreeding | |
Synonyms | |
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The hooded merganser (Lophodytes cucullatus) is a species of fish-eating duck in the subfamily Anatinae. It is the only extant species in the genus Lophodytes. The genus name derives from the Greek language: lophos meaning 'crest', and dutes meaning 'diver'. The bird is striking in appearance; both sexes have crests that they can raise or lower, and the breeding plumage of the male is handsomely patterned and coloured. The hooded merganser has a sawbill but is not classified as a typical merganser.
Hooded mergansers are the second-smallest species of merganser, with only the smew of Europe and Asia being smaller, and it also is the only merganser whose native habitat is restricted to North America.
A species of fossil merganser from the Late Pleistocene of Vero Beach, Florida, was described as Querquedula floridana (a genus now included in Anas ), but upon reexamination turned out to be a species closely related to the hooded merganser; it is now named Lophodytes floridanus, but the exact relationship between this bird and the modern species is unknown.
The hooded merganser was formally described in 1758 by the Swedish naturalist Carl Linnaeus in the tenth edition of his Systema Naturae under the binomial name Mergus cucullatus. [2] Linnaeus based his account on the "round-crested duck" that had been described and illustrated by the English naturalist Mark Catesby in the first volume of his The Natural History of Carolina, Florida and the Bahama Islands that was published between 1729 and 1732. [3] Linnaeus specified the type location as America but this was restricted to Virginia and Carolina following Catesby. [4] The hooded merganser is now the only species placed in the genus Lophodytes that was introduced in 1853 by the German naturalist Ludwig Reichenbach. [5] [6] The species is monotypic: no subspecies are recognised. [6] The genus name combines the Ancient Greek lophos meaning "crest" with dutēs meaning "diver". The specific epithet cucullatus is Latin meaning "hooded". [7]
The hooded merganser is a sexually dimorphic species. The adult female has a greyish-brown body, with a narrow white patch over the lower breast and belly. She has a light reddish-brown crest extending from the back of the head. During the nonbreeding season the male looks similar to the female, except that his eyes are yellow and the female's eyes are brown.
In breeding plumage the dorsal areas and the head, neck and breast of the mature male are mainly black with white markings; there are large white patches on either side of the crest, and they are particularly conspicuous when he raises his crest during courtship. His lower flanks are a rich reddish-brown or chestnut in colour, and the breast and undersides are more or less white, extending into white stripes across the crop and breast.
In both sexes there are narrow white stripes along the tertial wing feathers; when the bird is in repose they have the appearance of longitudinal white stripes along the bird's lower back, if they are visible. [8]
First-winter birds differ from adult females in appearance in that they have a grey-brown neck and upper parts; the upper parts of adult females are much darker — nearly black. Furthermore, the young birds have narrower white edges to their tertial feathers than adults do. Females of all ages are dark-eyed, whereas in males the eyes become pale during their first winter. [9]
Measurements: [10]
Hooded mergansers are short-distance migrants, and they winter in the United States in regions where winter temperatures allow for ice-free conditions on ponds, lakes and rivers. They have two major year-round ranges. One is in the eastern United States from the southern Canada–US border along the Atlantic Coast to the Gulf Coast in the region of the Mississippi delta. A smaller year-round range extends from Washington state and southern British Columbia to northern Idaho. They also breed to some extent in regions from Missouri to southern Canada and from Nova Scotia to eastern North Dakota and Saskatchewan, migrating when necessary to avoid winter conditions. [11] From 1966 - 2015, the hooded merganser experienced a >1.5% yearly population increase throughout its breeding range. [12]
For preference the hooded merganser lives on small bodies of water such as ponds and small estuaries where there is ample emergent aquatic vegetation, but it also inhabits larger wetlands, impoundments, flooded timber, and rivers. They prefer fresh water but do occur on brackish water bodies as well. [13]
Although the hooded merganser is a common species in captivity in Europe and most specimens recorded in the wild are regarded as escapes, or feral animals, a small number of birds have been regarded as genuinely wild vagrants. Britain's current first accepted record is a bird which was seen on North Uist in October 2000. [14] Small numbers are seen regularly in Dublin, but these are presumed to be feral.
The hooded merganser is a diving predator that largely hunts by sight while under water. Most studies report that its diet varies according to circumstances, usually being dominated by fish (44 to 81%). In addition it feeds on aquatic insects (13 to 20% of its diet) and other aquatic invertebrates such as crabs and crayfish (22 to 50%). [15]
Males and females of the hooded merganser form monogamous pairs and they remain together until the female has selected a nesting cavity and completed laying her clutch. After that, the male leaves the female to incubate and care for the brood. Females will actively seek out cavities in dead trees or artificial nest boxes such as those provided for nesting wood ducks. They prefer cavities 4–15 feet off the ground. Breeding occurs anytime between the end of February and the end of June, depending on the region.
The female will lay a clutch of 7-15 eggs but only begins incubation when the last egg has been laid, thereby permitting synchronous hatching. All hatchlings are consequently of the same size, which facilitates efficient parental care. During incubation, the female may lose anywhere from 8% to 16% of her body weight.
Like most waterfowl, hooded merganser hatchlings are precocial and usually leave the nest within 24 hours after they hatch; this is about long enough to accommodate synchronous hatching. Once they leave the nest, the young are capable of diving and foraging, but remain with the female for warmth and protection. [16]
Population declines in the past have been linked with large scale deforestation. Because these waterfowl are cavity nesters, they require mature trees in which suitable nesting sites are likely to be found. It has been suggested that in recent years proper timber management is increasing available habitat successfully. One priority consideration when managing wooded habitat for cavity nesting ducks, is to maintain a sufficient population of mature trees in which suitable nesting cavities would be plentiful. [17] In addition these ducks do make use of artificial nest boxes when available. [18]
Because of their high reliance on aquatic prey, hooded mergansers are very susceptible to harm from many types of pollution, some of which are poisons that accumulate in the food organisms, directly poisoning predators high in the food chain, and some of which simply reduce the populations of their prey. [17] [19] [20]
The sea ducks (Mergini) are a tribe of the duck subfamily of birds, the Anatinae. The taxonomy of this group is incomplete. Some authorities separate the group as a subfamily, while others remove some genera. Most species within the group spend their winters near coastal waters. Many species have developed specialized salt glands to allow them to tolerate salt water, but these are poorly developed in juveniles. Some of the species prefer riverine habitats. All but two of the 22 species in this group live in far northern latitudes.
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 gadwall is a common and widespread dabbling duck in the family Anatidae.
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 wood duck or Carolina duck is a species of perching duck found in North America. The drake wood duck is one of the most colorful North American waterfowls.
The common merganser or goosander (Eurasian) is a large sea duck of rivers and lakes in forested areas of Europe, Asia, and North America. The common merganser eats mainly fish. It nests in holes in trees.
The red-breasted merganser is a duck species that is native to much of the Northern Hemisphere. The red breast that gives the species its common name is only displayed by males in breeding plumage. Individuals fly rapidly, and feed by diving from the surface to pursue aquatic animals underwater, using serrated bills to capture slippery fish. They migrate each year from breeding sites on lakes and rivers to their mostly coastal wintering areas, making them the only species in the genus Mergus to frequent saltwater. They form flocks outside of breeding season that are usually small but can reach 100 individuals. The worldwide population of this species is stable, though it is threatened in some areas by habitat loss and other factors.
Mergus is the genus of the typical mergansers fish-eating ducks in the subfamily Anatinae. The genus name is a Latin word used by Pliny the Elder and other Roman authors to refer to an unspecified waterbird.
The common goldeneye or simply goldeneye is a medium-sized sea duck of the genus Bucephala, the goldeneyes. Its closest relative is the similar Barrow's goldeneye. The genus name is derived from the Ancient Greek boukephalos, a reference to the bulbous head shape of the bufflehead. The species name is derived from the Latin clangere.
The bufflehead is a small sea duck of the genus Bucephala, the goldeneyes. It breeds in Alaska and Canada and migrates in winter to southern North America. This species was first described by Carl Linnaeus in his landmark 1758 10th edition of Systema Naturae as Anas albeola.
The eastern bluebird is a small North American migratory thrush found in open woodlands, farmlands, and orchards.
The pileated woodpecker is a large, mostly black woodpecker native to North America. An insectivore, it inhabits deciduous forests in eastern North America, the Great Lakes, the boreal forests of Canada, and parts of the Pacific Coast. It is the largest confirmed extant woodpecker species in North America, with the possible exception of the ivory-billed woodpecker, which the U.S. Fish and Wildlife Service has proposed be reclassified as extinct. It is also the third largest species of woodpecker in the world, after the great slaty woodpecker and the black woodpecker. "Pileated" refers to the bird's prominent red crest, from the Latin pileatus meaning "capped".
The northern flicker or common flicker is a medium-sized bird of the woodpecker family. It is native to most of North America, parts of Central America, Cuba, and the Cayman Islands, and is one of the few woodpecker species that migrate. Over 100 common names for the northern flicker are known, including yellowhammer, clape, gaffer woodpecker, harry-wicket, heigh-ho, wake-up, walk-up, wick-up, yarrup, and gawker bird. Many of these names derive from attempts to imitate some of its calls. It is the state bird of Alabama.
The red-headed woodpecker is a mid-sized woodpecker found in temperate North America. Its breeding habitat is open country across southern Canada and the east-central United States. It is rated as least concern on the International Union for Conservation of Nature (IUCN)'s Red List of Endangered species, having been down-listed from near threatened in 2018.
The red-bellied woodpecker is a medium-sized woodpecker of the family Picidae. It breeds mainly in the eastern United States, ranging as far south as Florida and as far north as Canada. Though it has a vivid orange-red crown and nape it is not to be confused with the red-headed woodpecker, a separate species of woodpecker in the same genus with an entirely red head and neck that sports a solid black back and white belly. The red-bellied earns its name from the pale reddish blush of its lower underside.
The eastern meadowlark is a medium-sized blackbird, very similar in appearance to sister species western meadowlark. It occurs from eastern North America to northern South America, where it is also most widespread in the east. The Chihuahuan meadowlark was formerly considered to be conspecific with the eastern meadowlark.
The hooded oriole is a medium-sized New World oriole. The male of this species ranges in color from a bright orange to a paler yellow, with a black back, face, tail and bib, with the wing containing two white bars. The female is more of an olive color with some yellow accents.
The great crested flycatcher is a large insect-eating bird of the tyrant flycatcher family. It is the most widespread member of the genus Myiarchus in North America, and is found over most of the eastern and mid-western portions of the continent. It dwells mostly in the treetops and rarely is found on the ground.
The black-bellied whistling duck, formerly called the black-bellied tree duck, is a whistling duck that before 2000 bred mainly in the southernmost United States, Mexico, and tropical Central to south-central South America. It can be found year-round in much of the United States. It has been recorded in every eastern state and adjacent Canadian province. Since it is one of only two whistling duck species native to North America, it is occasionally just known as the "whistling duck" or "Mexican squealer" in the southern USA.
The purple martin is a passerine bird in the swallow family Hirundinidae. It is the largest swallow in North America. Despite its name, the purple martin is not truly purple. The dark blackish-blue feathers have an iridescent sheen caused by the diffraction of incident light giving them a bright blue to navy blue or deep purple appearance. In some light, they may even appear green in color.