The redhead (''Aythya americana'') is a medium-sized

diving duck The diving ducks, commonly called pochards or scaups, are a category of duck which feed by diving beneath the surface of the water. They are part of Anatidae, the diverse and very large family that includes ducks, geese, and swans. The diving d ...

. The scientific name is derived from

Greek Greek may refer to: Greece Anything of, from, or related to Greece, a country in Southern Europe: *Greeks, an ethnic group. *Greek language, a branch of the Indo-European language family. **Proto-Greek language, the assumed last common ancestor ...

''aithuia'', an unidentified

seabird Seabirds (also known as marine birds) are birds that are adapted to life within the marine environment. While seabirds vary greatly in lifestyle, behaviour and physiology, they often exhibit striking convergent evolution, as the same enviro ...

mentioned by authors including Hesychius and

Aristotle Aristotle (; grc-gre, Ἀριστοτέλης ''Aristotélēs'', ; 384–322 BC) was a Greek philosopher and polymath during the Classical period in Ancient Greece. Taught by Plato, he was the founder of the Peripatetic school of ph ...

, and

Latin Latin (, or , ) is a classical language belonging to the Italic branch of the Indo-European languages. Latin was originally a dialect spoken in the lower Tiber area (then known as Latium) around present-day Rome, but through the power of the ...

''americana'', of America. The redhead is long with an wingspan. Redhead weight ranges from 2.0 to 2.5 lbs (907-1134 g), with males weighing an average of 2.4 lbs (1089 g) and females weighing an average of 2.1 lbs (953 g). It belongs to the genus

Aythya ''Aythya'' is a genus of diving ducks. It has twelve described species. The name ''Aythya'' comes from the Ancient Greek word (), which may have referred to a sea-dwelling duck or an auklet. ''Aythya shihuibas'' was described from the Late Mi ...

, together with 11 other described species. The redhead and the

common pochard The common pochard (; ''Aythya ferina'') 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 ''ferina'', "wild game", ...

form a sister group which together is sister to the

canvasback The canvasback (''Aythya valisineria'') is a species of diving duck, the largest found in North America. Taxonomy Scottish-American naturalist Alexander Wilson described the canvasback in 1814. The genus name is derived from Greek ''aithuia'', ...

. The redhead goes by many names, including the red-headed duck and the red-headed pochard. This

waterfowl Anseriformes is an order of birds also known as waterfowl that comprises about 180 living species of birds in three families: Anhimidae (three species of screamers), Anseranatidae (the magpie goose), and Anatidae, the largest family, which i ...

is easily distinguished from other ducks by the male's copper coloured head and bright blue bill during the breeding season.

Taxonomy and phylogeny

Taxonomy

The redhead is in the family

Anatidae The Anatidae are the biological family of water birds that includes ducks, geese, and swans. The family has a cosmopolitan distribution, occurring on all the world's continents except Antarctica. These birds are adapted for swimming, floating ...

(ducks, swans, geese) and genus ''

'' (diving ducks). There are currently no described subspecies of the redhead. The two syntype specimens of ''Fuligula americana'' Eyton
Monogr. Anat., 1838, p.155
are held in the vertebrate zoology collections of

National Museums Liverpool National Museums Liverpool, formerly National Museums and Galleries on Merseyside, comprises several museums and art galleries in and around Liverpool, England. All the museums and galleries in the group have free admission. The museum is a non ...

World Museum World Museum is a large museum in Liverpool, England which has extensive collections covering archaeology, ethnology and the natural and physical sciences. Special attractions include the Natural History Centre and a planetarium. Entry to the ...

, with accession numbers NML-VZ D829 (male immature) and NML-VZ D829a (female adult). The specimens were collected in North America and came to the Liverpool national collection via

Thomas Campbell Eyton Thomas Campbell Eyton JP, DL (10 September 1809 – 25 October 1880) was an English naturalist whose fields were cattle, fishes and birds. He was a friend and correspondent of Charles Darwin though he opposed his theories. Eyton was born at ...

’s collection and the 13th Earl of Derby’s collection which was bequeathed to the city of Liverpool.

Phylogeny

The redhead and the

form a sister group which itself is sister to the

. This group is then sister to the monophyletic group consisting of the white-eyes (

hardhead The hardhead (''Aythya australis''), also known as the white-eyed duck, is the only true diving duck found in Australia. The common name "hardhead" has nothing to do with the density of the bird's skull, instead referring to the difficulty encou ...

Madagascar pochard The Madagascar pochard or Madagascan pochard (''Aythya innotata''; mg, Fotsy maso, Onjo) is an extremely rare diving duck of the genus ''Aythya''. Thought to be extinct in the late 1990s, specimens of the species were rediscovered at Lake Matsa ...

, and the sister species

ferruginous duck The ferruginous duck (''Aythya nyroca''), also known as ferruginous pochard, common white-eye or white-eyed pochard, is a medium-sized diving duck from Eurosiberia. The scientific name is derived from Greek '' aithuia'' an unidentified seabir ...

and

baer's pochard Baer's pochard (''Aythya baeri'') is a diving duck found in eastern Asia. It is a resident bird in North and Central China, formerly bred in southeast Russia and Northeast China, migrating in winter to southern China, Vietnam, Japan, and Indi ...

) and scaups ( New Zealand scaup,

ring-necked duck The ring-necked duck (''Aythya collaris'') is a diving duck from North America commonly found in freshwater ponds and lakes. The scientific name is derived from Greek , an unidentified seabird mentioned by authors including Hesychius and Arist ...

tufted duck The tufted duck or tufted pochard (''Aythya fuligula'') is a small diving duck with a population of close to one million birds, found in northern Eurasia. The scientific name is derived from Ancient Greek '' aithuia'', an unidentified seabird ment ...

greater scaup The greater scaup (''Aythya marila''), just scaup in Europe or, colloquially, "bluebill" in North America, is a mid-sized diving duck, larger than the closely related lesser scaup. It spends the summer months breeding in Alaska, northern Canad ...

lesser scaup The lesser scaup (''Aythya affinis'') is a small North American diving duck that migrates south as far as Central America in winter. It is colloquially known as the little bluebill or broadbill because of its distinctive blue bill. The origin of ...

Description

The redhead is a pochard, a diving duck specially adapted to foraging underwater. Their legs are placed farther back on the body, which makes walking on land difficult, the webbing on their feet is larger than dabbling ducks and their bills are broader, to facilitate underwater foraging. In addition, pochards have a lobed hind toe. No pochard has a metallic coloured speculum, something that is characteristic of other ducks.

Males

During breeding season, adult males have a copper head and neck, with a black breast. The back and sides are grey, the belly is white and the rump and tail are a light black. Male bills are pale blue with a black tip and a thin ring separating the two colours. Non breeding males lose the copper colour and instead have brown heads.

Females

Adult females, however, have a yellow to brown head and neck. The breast is brown, the belly is white and the rest of the body is a grey to brown. The female bills are slate with a dark tip that is separated by a blue ring. Females remain the same colour year round.

Distribution

During breeding season, redheads are found across a wide range of North America, from as far north as Northern Canada to the Caribbean. Their preferred areas include the intermontane regions of British Columbia, Alberta, Saskatchewan, Manitoba, and the Dakotas with some small localities in Ontario, Quebec and southern United States. These pochards then migrate south to winter in warmer climates. These areas include southern United States where breeding does not occur and extends to Mexico, Guatemala, Cuba, and the Bahamas. In either season, redheads use wetlands as their main habitat.

Habitat

Small, semi-permanent

wetland A wetland is a distinct ecosystem that is flooded or saturated by water, either permanently (for years or decades) or seasonally (for weeks or months). Flooding results in oxygen-free (anoxic) processes prevailing, especially in the soils. The p ...

s in non-forested country where the water is deep enough to provide dense emergent vegetation is considered ideal breeding

habitat In ecology, the term habitat summarises the array of resources, physical and biotic factors that are present in an area, such as to support the survival and reproduction of a particular species. A species habitat can be seen as the physical ...

for redheads. When wintering, redheads switch to large areas of water near the coast that are protected from wave action but can also be found in

reservoir A reservoir (; from French ''réservoir'' ) is an enlarged lake behind a dam. Such a dam may be either artificial, built to store fresh water or it may be a natural formation. Reservoirs can be created in a number of ways, including contro ...

lake A lake is an area filled with water, localized in a basin, surrounded by land, and distinct from any river or other outlet that serves to feed or drain the lake. Lakes lie on land and are not part of the ocean, although, like the much large ...

s, playa wetlands, freshwater river deltas, coastal marshes,

estuaries An estuary is a partially enclosed coastal body of brackish water with one or more rivers or streams flowing into it, and with a free connection to the open sea. Estuaries form a transition zone between river environments and maritime environmen ...

and bays. Redhead female RWD2

Predators

Redheads do not have many

predators Predation is a biological interaction where one organism, the predator, kills and eats another organism, its prey. It is one of a family of common feeding behaviours that includes parasitism and micropredation (which usually do not kill th ...

and are most likely to die of disease or indirect human impact. These ducks are considered less desirable as table fare than their puddle duck cousins like the mallard; however, their beautiful plumage makes them a targeted species for waterfowl hunters looking to focus on diving ducks. Adults can be preyed upon by northern river otters,

red-tailed hawk The red-tailed hawk (''Buteo jamaicensis'') is a bird of prey that breeds throughout most of North America, from the interior of Alaska and northern Canada to as far south as Panama and the West Indies. It is one of the most common members wit ...

great horned owl The great horned owl (''Bubo virginianus''), also known as the tiger owl (originally derived from early naturalists' description as the "winged tiger" or "tiger of the air"), or the hoot owl, is a large owl native to the Americas. It is an extre ...

s, bald eagles,

golden eagle The golden eagle (''Aquila chrysaetos'') is a bird of prey living in the Northern Hemisphere. It is the most widely distributed species of eagle. Like all eagles, it belongs to the family Accipitridae. They are one of the best-known birds of ...

s and to a greater extent, minks. Most predation comes in the form of duckling predation and egg foraging.

Northern pike The northern pike (''Esox lucius'') is a species of carnivorous fish of the genus ''Esox'' (the pikes). They are typical of brackish and fresh waters of the Northern Hemisphere (''i.e.'' holarctic in distribution). They are known simply as a p ...

and

snapping turtles The Chelydridae is a family of turtles that has seven extinct and two extant genera. The extant genera are the snapping turtles, ''Chelydra'' and ''Macrochelys''. Both are endemic to the Western Hemisphere. The extinct genera are ''Acherontemys' ...

are known to eat ducklings whereas skunks, minks,

crows The Common Remotely Operated Weapon Station (CROWS) is a series of remote weapon stations used by the US military on its armored vehicles and ships. It allows weapon operators to engage targets without leaving the protection of their vehicle. ...

and magpies will steal and eat redhead eggs.

Population status

The

North American Waterfowl Management Plan The North American Waterfowl Management Plan (NAWMP) is an international plan to conserve waterfowl and migratory birds in North America. It was established in 1986 by Canada and the United States, and expanded to include Mexico in 1994. In the Uni ...

for redheads is 760,000 North American birds. The population size has increased in the past few decades to well over 1.4 million birds. Redheads make up 2% of North America's duck population and only 1% of its harvested ducks. Populations may be stable because of restrictive bag limits for the species. In addition, the species uses semi-permanent and permanent wetlands to breed and these habitats are less likely to be affected by drought. For future management of the species, organizations are looking into wetland conservation.

Behaviour

Migration

Spring

Redheads leave their winter range in late January and February with all birds migrating by mid-March. In western North America, migrants begin arriving in Oregon, British Columbia and Colorado in February. In central North America, migrants arrive as soon as temperatures open wetlands and lakes, which can range from late February (Nebraska) to early May (Alberta, Manitoba and Iowa). In the

Great Lakes region The Great Lakes region of North America is a binational Canadian–American region that includes portions of the eight U.S. states of Illinois, Indiana, Michigan, Minnesota, New York, Ohio, Pennsylvania and Wisconsin along with the Canadian p ...

and north-eastern North America, migrants will also arrive as soon as bodies of water open up.Woodin, Marc C. and Thomas C. Michot. 2002. Redhead (Aythya americana), The Birds of North America Online (A. Poole, Ed.). Ithaca: Cornell Lab of Ornithology; Retrieved from the Birds of North America Online: http://bna.birds.cornell.edu/bna/species/695 doi:10.2173/bna.695

Fall

Western birds migrate through Great Basin to the Pacific Coast. In British Columbia, fall migration begins in September and continues through October. The Great Salt Lake region is of particular importance to migrants in western United States. Central North American redheads will begin migrating earlier, around August/September and go through the Great Plains to the

Texas Texas (, ; Spanish: ''Texas'', ''Tejas'') is a state in the South Central region of the United States. At 268,596 square miles (695,662 km2), and with more than 29.1 million residents in 2020, it is the second-largest U.S. state by ...

coast. Eastern populations will migrate through the

to the Atlantic Coast or Florida from October to November. Most redheads winter along the

Gulf of Mexico The Gulf of Mexico ( es, Golfo de México) is an ocean basin and a marginal sea of the Atlantic Ocean, largely surrounded by the North American continent. It is bounded on the northeast, north and northwest by the Gulf Coast of the United ...

(offshore Louisiana, Florida and Mexico) however eastern populations will winter in South Carolina.

Reproduction

Mating

Redheads flock together on

s and other bodies of water but will migrate in pairs, which are formed in December or January through elaborate courtship rituals. Unpaired redheads will migrate together in a ‘courting party’ that can be up to 25 individuals strong and hopefully find a mate within the group. The pair bonds are established yearly through a long courtship process. Males begin this process through neck-kinking and head throwing

displays A display device is an output device for presentation of information in visual or tactile form (the latter used for example in tactile electronic displays for blind people). When the input information that is supplied has an electrical signal the ...

while emitting a cat-like call. The male will continue by initiating a neck-stretching display while producing a cough like call, a display and vocalization in which the females reciprocates. If interested, the female will herself produce inciting calls towards the male while performing alternate lateral and chin lifting movements. The male then swims ahead of her and turns the back of his head towards the female. Once courtship is finished, the two birds are paired for the year. Eventually, the male initiates copulation by alternating bill dipping and

preening Preening is a found in birds that involves the use of the beak to position feathers, interlock feather that have become separated, clean plumage, and keep ectoparasites in check. Feathers contribute significantly to a bird's insulation, waterp ...

dorsally towards the female, an action in which the female might return to the male.

Nesting

Once copulation is completed, female redheads begin forming

nests A nest is a structure built for certain animals to hold eggs or young. Although nests are most closely associated with birds, members of all classes of vertebrates and some invertebrates construct nests. They may be composed of organic materi ...

. They are built with thick and strong plant material in emergent vegetation, such as hard stem bulrush,

cattails ''Typha'' is a genus of about 30 species of monocotyledonous flowering plants in the family Typhaceae. These plants have a variety of common names, in British English as bulrush or reedmace, in American English as reed, cattail, or punks, in ...

and

sedges The Cyperaceae are a family of graminoid (grass-like), monocotyledonous flowering plants known as sedges. The family is large, with some 5,500 known species described in about 90 genera, the largest being the "true sedges" genus ''Carex'' wit ...

, over or near standing water. Redheads do not defend their

territory A territory is an area of land, sea, or space, particularly belonging or connected to a country, person, or animal. In international politics, a territory is usually either the total area from which a state may extract power resources or a ...

home range A home range is the area in which an animal lives and moves on a periodic basis. It is related to the concept of an animal's territory which is the area that is actively defended. The concept of a home range was introduced by W. H. Burt in 1943. He ...

and are actually very

social Social organisms, including human(s), live collectively in interacting populations. This interaction is considered social whether they are aware of it or not, and whether the exchange is voluntary or not. Etymology The word "social" derives from ...

while in their breeding ground. This is thought to occur because some younger, inexperienced redhead females parasitize other pochards. Some redheads lay their eggs in other pochards’ nests, including the

and greater and

s and this social parasitism by redheads reduces the hatching success of other pochards’ eggs, especially those of the

. In contrast, because of the parasitic relationship between the redhead and other pochards, redhead hybrids with the

and the greater and

s have been found.

Canvasback The canvasback (''Aythya valisineria'') is a species of diving duck, the largest found in North America. Taxonomy Scottish-American naturalist Alexander Wilson described the canvasback in 1814. The genus name is derived from Greek ''aithuia'', ...

x redhead hybrids can be fertile. Brood sizes range from 5-7 young, with the mother abandoning the chicks at 8 weeks old, before they are capable of flying.Mitchell Custer, C. (1993). 13.1. 11. Life History Traits and Habitat Needs of the Redhead. ''Waterfowl Management Handbook'', 40. They remain flightless for another 2–4 weeks.

Vocalizations

There is little information on redhead vocalizations outside of breeding calls. Males will emit calls when

courting Courtship is the period wherein some couples get to know each other prior to a possible marriage. Courtship traditionally may begin after a betrothal and may conclude with the celebration of marriage. A courtship may be an informal and private ...

the female. When the neck is fully extended in the neck-stretching display, males will emit a distinct ''wheee-oww,'' which sounds catlike. Males may also produce a soft coughing call, although this call is less frequent. Females will emit a soft ''errrr'' note when she is inciting a male.

Feeding habits

All pochards have similar

diets The Low Countries comprise the coastal Rhine–Meuse–Scheldt delta region in Western Europe, whose definition usually includes the modern countries of Luxembourg, Belgium and the Netherlands. Both Belgium and the Netherlands derived their ...

that include both plant and animal materials. Redheads undergo a niche switch when breeding and when wintering. During the breeding season, redheads will eat as much animal matter as possible, including

gastropods The gastropods (), commonly known as snails and slugs, belong to a large taxonomic class of invertebrates within the phylum Mollusca called Gastropoda (). This class comprises snails and slugs from saltwater, from freshwater, and from land. The ...

, mollusks and insect larvae. They will eat the occasional grass and other emergent vegetation. However, once they fly south, redheads will change their diet to include mostly plant material, including

pondweed Pondweed refers to many species and genera of aquatic plants and green algae: *''Potamogeton'', a diverse and worldwide genus *''Elodea'', found in North America *''Aponogeton'', in Africa, Asia and Australasia *''Groenlandia ''Groenlandia'' is ...

wild rice Wild rice, also called manoomin, Canada rice, Indian rice, or water oats, is any of four species of grasses that form the genus ''Zizania'', and the grain that can be harvested from them. The grain was historically gathered and eaten in both ...

, wild celery, wigeon grass,

bulrush Bulrush is a vernacular name for several large wetland grass-like plants *Sedge family (Cyperaceae): **''Cyperus'' **'' Scirpus'' **''Blysmus'' **''Bolboschoenus'' **'' Scirpoides'' **'' Isolepis'' **'' Schoenoplectus'' **'' Trichophorum'' * T ...

es, muskgrass and shoal grass. Gastropods known as food of ''Aythya americana'' include: '' Acteocina canaliculata'', '' Acteon punctostriatus'', '' Anachis avara'', '' Anachis obesa'', '' Caecum nitidum'', ''

Calliostoma ''Calliostoma'' is a genus of small to medium-sized sea snails with gills and an operculum, marine gastropod molluscs within the family Calliostomatidae, the Calliostoma top snails. Previously this genus was placed within the family Trochida ...

'' sp., ''Cerithidea pliculosa'', '' Cerithium lutosum'', '' Crepidula convexa'', '' Diastoma varium'', '' Melanella'' sp., '' Mitrella lunata'', ''

Nassarius acutus ''Nassarius acutus'', common name the sharp nassa, is a species of sea snail, a marine gastropod mollusc in the family Nassariidae The Nassariidae, Nassa mud snails (USA), or dog whelks (UK), are a taxonomic family of small to medium-sized s ...

'', '' Nassarius vibex'', '' Natica'' sp., ''

Neritina virginea ''Vitta virginea'', the Virgin Nerite, is a species of sea snail, a marine gastropod mollusk in the family Neritidae. Distribution This species is widespread from the Bahamas, Bermuda, Cuba, West Indies, Greater and Lesser Antilles, Dominica, ...

'', '' Odostomia trifida'', '' Olivella minuta'', '' Olivella watermani'', '' Polinices'' sp.,

Pyramidellidae Pyramidellidae, common name the pyram family, or pyramid shells, is a voluminous taxonomic family of mostly small and minute ectoparasitic sea snails, marine heterobranch gastropod molluscs. The great majority of species of pyrams are micr ...

, '' Pyrgocythara plicosa'', '' Rissoina catesbyana'', '' Sayella livida'', ''

Turbonilla ''Turbonilla'' is a large genus of ectoparasitic sea snails, marine gastropod molluscs in the family Pyramidellidae, the pyrams and their allies.Bouchet, P.; Gofas, S. (2011). ''Turbonilla'' Risso, 1826. Accessed through: World Register o ...

'' sp., '' Turbonilla interrupta'' and '' Vitrinella'' sp. File:Redhead duck 1.jpg, Breeding male File:Aytya americana jcwf1.JPG, Breeding male File:Aythya americana female.jpg, Female

References

External links

Redhead Species Account
- Cornell Lab of Ornithology

- USGS Patuxent Bird Identification InfoCenter *
SoundSound metadata
Macaulay Library, Cornell Lab of Ornithology * * {{Taxonbar, from=Q692192 Aythya Birds of North America Birds of Mexico Birds of the Greater Antilles Birds of the Bahamas Birds of Canada Birds of the Turks and Caicos Islands Birds of Bermuda Birds described in 1838 Taxa named by Thomas Campbell Eyton