Redhead (bird)

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Redhead
male
Female with young

Least Concern (IUCN 3.1)[1]
Scientific classification Edit this classification
Domain: Eukaryota
Kingdom: Animalia
Phylum: Chordata
Class: Aves
Order: Anseriformes
Family: Anatidae
Genus: Aythya
Species:
A. americana
Binomial name
Aythya americana
(Eyton, 1838)

The redhead (Aythya americana) 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.[2] 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 (907–1134 g),[3] with males weighing an average of 2.4 lbs (1089 g) and females weighing an average of 2.1 lbs (953 g).[4] 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.[5]

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

breeding season.[7]

Taxonomy and phylogeny

Taxonomy

The redhead is in the family Anatidae (ducks, swans, geese) and genus Aythya (diving ducks). There are currently no described subspecies of the redhead.[6]

The two

13th Earl of Derby’s collection which was bequeathed to the city of Liverpool.[8]

Phylogeny

The redhead and the common pochard form a sister group which itself is sister to the canvasback.[5] This group is then sister to the monophyletic group consisting of the white-eyes (hardhead, Madagascar pochard, and the sister species ferruginous duck and baer's pochard) and scaups (New Zealand scaup, ring-necked duck, tufted duck, greater scaup, lesser scaup).[5]

Description

The redhead is a

dabbling ducks and their bills are broader, to facilitate underwater foraging. In addition, pochards have a lobed hind toe.[6] No pochard has a metallic coloured speculum, something that is characteristic of other ducks.[10]

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.[7]

Females

Female

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.[7]

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.[6][7] In either season, redheads use wetlands as their main habitat.[7]

Habitat

Small, semi-permanent

Predators

Redheads do not have many

crows and magpies will steal and eat redhead eggs.[6][12]

Population status

The North American Waterfowl Management Plan for redheads is 760,000 North American birds.[13] The population size has increased in the past few decades to well over 1.4 million birds.[7] Redheads make up 2% of North America's duck population and only 1% of its harvested ducks.[13] 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.[13]

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 and north-eastern North America, migrants will also arrive as soon as bodies of water open up.[14]

Fall

Western birds migrate through

Atlantic Coast or Florida from October to November. Most redheads winter along the Gulf of Mexico (offshore Louisiana, Florida and Mexico) however eastern populations will winter in South Carolina.[14]

Reproduction

Mating

Neck-stretching courtship ritual of the male redhead

Redheads flock together on

preening dorsally towards the female, upon which the female may return to the male.[10]

Nesting

Once copulation is completed, female redheads begin forming nests. They are built with thick and strong plant material in emergent vegetation, such as hard stem bulrush, cattails and sedges, over or near standing water.[6][12] Redheads do not defend their territory or home range; they are instead social while in their breeding ground. This is thought to facilitate brood parasitism on other pochards, which is particularly prevalent on the part of younger, less experienced redhead females.[6] In this process, redheads lay their eggs in other pochards’ nests, including the canvasback, ring-necked duck and greater and lesser scaups, and this parasitism by redheads reduces the hatching success of other pochards’ eggs, especially those of the canvasback.[6] The parasitic relationship between the redhead and other pochards promotes hybridization between the species; redhead hybrids with the ring-necked duck, canvasback and the greater and lesser scaups have been found.[10] Canvasback × redhead hybrids can be fertile.[15] Brood sizes range from 5 to 7 young, with the mother abandoning the chicks at 8 weeks old, 2–4 weeks before they are capable of flight.[13]

Vocalizations

There is little information on redhead vocalizations outside of breeding calls. When the neck is fully extended in the neck-stretching display, males emit a cat-like wheee-oww.[6][10] Males may also produce a soft coughing call, although this call is less frequent.[6] Females emit a soft errrr note when inciting a male.[6]

Feeding habits

All pochards have similar

emergent vegetation.[7] However, once they fly south, redheads will change their diet to include mostly plant material, including pondweeds, wild rice, wild celery, wigeon grass, bulrushes, muskgrass and shoal grass.[6][7]

Gastropods known as food of Aythya americana include:

  • Breeding male
    Breeding male
  • Breeding male
    Breeding male
  • Female
    Female

References

  1. . Retrieved 12 November 2021.
  2. .
  3. ^ cosleyzoo. "Redhead Duck". Cosley Zoo. Retrieved 2020-09-25.
  4. ^ "Redhead | Types of Ducks & Geese". www.ducks.org. Retrieved 2020-09-25.
  5. ^
    JSTOR 4088937
    .
  6. ^ .
  7. ^ a b c d e f g h i j Johnson, W.P.; Lockwood, M. (2013). Texas Waterfowl. College Station (TX): Texas A & M University Press.
  8. ^ a b R. Wagstaffe (1978-12-01). Type Specimens of Birds in the Merseyside County Museums (formerly City of Liverpool Museums).
  9. .
  10. ^ a b c d Johnsgard, P.A. (1965). Handbook of Waterfowl Behavior. Ithaca (NY): Comstock Pub. Associates.
  11. ^
    S2CID 39784980
    .
  12. ^ a b c Baldassarre, G.A.; Bolen, E.G.; Saunders, D.A. (1994). Waterfowl Ecology and Management. New York: J. Wiley.
  13. ^ a b c d Mitchell Custer, C. (1993). 13.1. 11. Life History Traits and Habitat Needs of the Redhead. Waterfowl Management Handbook, 40.
  14. ^ a b c 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
  15. ^ Woodin, Marc. C.; Michot, Thomas C. (2015). "Redhead Aythya americana Order ANSERIFORMES – Family ANATIDAE". The Birds Of North America Online. CORNELL LAB OF ORNITHOLOGY and the AMERICAN ORNITHOLOGISTS' UNION. Retrieved October 7, 2015.
  16. ^ Michot, T. C.; Woodin, M. C.; Nault, A. J. (2008). "Food habits of redheads (Aythya americana) wintering in seagrass beds of coastal Louisiana and Texas, USA" (PDF). Acta Zoologica Academiae Scientiarum Hungaricae. 54 (Suppl. 1): 239–250.

External links