Red-billed Duck Anas erythrorhyncha Scientific name definitions

43–48 cm; male 345–954 g, female 338–955 g (1 Kear, J., Editor (2005). Ducks, Geese and Swans. Volume 1: General chapters, and Species accounts (Anhima to Salvadorina). Oxford University Press, Oxford, UK. Close ). Might be confused Spatula hottentota, which has buff cheeks and blue bill, while on Madagascar could also be mistaken for Anas bernieri, which has pale (white) greater coverts (not secondaries) and lacks dark cap and red bill of present species. Cinnamon-buff speculum  ; neck variable, can be paler or darker than in illustration. Overall greyish with dark cap  and nape, and pale (sometimes white) cheeks  and face, while body feathers have pale fringes  , underparts  darker than breast, neck and body, underwing  dark; bright pinkish-red bill, with black base to mandible, dark grey legs and brown eyes. Male has no eclipse plumage, but can be brighter and more prominently scaled in breeding season. Female slightly smaller with somewhat duller bill and smaller speculum (2 Safford, R. J., and A. F. A. Hawkins, Editors (2013). The Birds of Africa. Volume 8. The Malagasy Region. Christopher Helm, London, UK. Close ). Juvenile more greyish and more streaked (less white, more buffy) on underparts, with brownish-pink bill.

SE Sudan and Ethiopia SW to Angola and S to Western Cape Province (South Africa); Madagascar.

Various types of wetland , preferably with shallow, still, fresh water and abundant floating and emergent vegetation , including lakes, marshes, dams and flooded fields, as well as small rivers on Madagascar; regularly feeds in rice fields (1 Kear, J., Editor (2005). Ducks, Geese and Swans. Volume 1: General chapters, and Species accounts (Anhima to Salvadorina). Oxford University Press, Oxford, UK. Close ). Occasionally recorded up to 1–2 offshore in Madagascar (2 Safford, R. J., and A. F. A. Hawkins, Editors (2013). The Birds of Africa. Volume 8. The Malagasy Region. Christopher Helm, London, UK. Close ). Recorded to 2300 m in Malawi (3 Dowsett-Lemaire, F., and R. J. Dowsett (2006). The Birds of Malawi: An Atlas and Handbook. Tauraco Press & Aves, Liège, Belgium. Close ) and to 2450 m in Ethiopia (4 Ash, J. S., and J. Atkins (2009). Birds of Ethiopia and Eritrea: An Atlas of Distribution. Christopher Helm, London, UK. Close ).

Mostly sedentary, but somewhat dispersive outside breeding season, with > 5% of ringing recoveries within S Africa involving movements of more than 1000 km, including migrations N along Angolan coast of up to 1800 km and even c. 2190 km, but little evidence of interchange between S & E Africa (1 Kear, J., Editor (2005). Ducks, Geese and Swans. Volume 1: General chapters, and Species accounts (Anhima to Salvadorina). Oxford University Press, Oxford, UK. Close ); movements often linked to extent of flooding, thus some populations speculated to be semi-nomadic (1 Kear, J., Editor (2005). Ducks, Geese and Swans. Volume 1: General chapters, and Species accounts (Anhima to Salvadorina). Oxford University Press, Oxford, UK. Close ), although recent study based at L Manyame (Botswana), Barberspan and Strandfontein (South Africa) found high consistency in species’ migrations (5 Cumming, G.S., Gaidet, N. and Ndlovu, M. (2012). Towards a unification of movement ecology and biogeography: conceptual framework and a case study on Afrotropical ducks. Journal of Biogeography. 39: 1401-1411. Close ). Birds ringed in Zambia recovered in South Africa, Zimbabwe, Botswana and Namibia (6 Dowsett, R. J., D. R. Aspinwall, and F. Dowsett-Lemaire (2008). The Birds of Zambia. Tauraco Press & Aves, Liège, Belgium. Close ), and a bird recovered in Malawi in Apr had been ringed in Transvaal (3 Dowsett-Lemaire, F., and R. J. Dowsett (2006). The Birds of Malawi: An Atlas and Handbook. Tauraco Press & Aves, Liège, Belgium. Close ), while in Kenya numbers peak in boreal winter, with birds arriving from unknown sources (7 Brown, L. H., E. K. Urban, and K. Newman (1982). The Birds of Africa. Volume 1. Academic Press, London, UK and New York, USA. Close ). Considered to be solely a migrant visitor to Uganda, with no records of breeding (8 Carswell, M., D. Pomeroy, J. Reynolds, and H. Tushabe (2005). The Bird Atlas of Uganda. British Ornithologists’ Club and British Ornithologists' Union, Oxford, UK. Close ), and perhaps mainly a visitor to S Somalia, in which country there is one record from extreme NE (9 Ash, J. S., and J. E. Miskell (1998). Birds of Somalia. Pica Press, Robertsbridge, UK. Close ). Three records in Israel (Jun–Jul 1968, summer 2014, Jan 2015) (10 Shirihai, H. (1996). The Birds of Israel: A Complete Avifauna and Bird Atlas of Israel. Academic Press, London, UK. Close , 11 van den Berg, A.B. (2015). WP reports. Dutch Birding. 37(2): 122–129. Close ) and there is some suggestion (albeit without direct evidence) that species moves between S Africa and Madagascar (1 Kear, J., Editor (2005). Ducks, Geese and Swans. Volume 1: General chapters, and Species accounts (Anhima to Salvadorina). Oxford University Press, Oxford, UK. Close ), which might also explain a single vagrant record from Aldabra (Seychelles) in Jan 2012 (12 Demey, R. (2012). Recent reports. Bulletin of the African Bird Club 19(2):221–236. Close , 2 Safford, R. J., and A. F. A. Hawkins, Editors (2013). The Birds of Africa. Volume 8. The Malagasy Region. Christopher Helm, London, UK. Close ).

Seeds, fruits, grain, roots and vegetative parts of aquatic plants, grasses and sedges; also aquatic invertebrates, chiefly molluscs, but also insects, beetles and crustaceans. On Kafue Flats, Zambia, during summer flooding (Nov–Feb) stomach contents of eight birds contained 45% animal matter, 32% vegetable matter (mainly leaves) and 23% seeds, thereafter sample of 28 contents contained 85% seeds, 10% other vegetable matter (mainly rhizomes) and 5% animal matter, while in W Transvaal 23 non-breeding birds had fed principally on animal matter (76%), the rest plant material, with maize seeds particularly important (7 Brown, L. H., E. K. Urban, and K. Newman (1982). The Birds of Africa. Volume 1. Academic Press, London, UK and New York, USA. Close ). In South Africa, both breeding and non-breeding individuals had fed principally on Panicum schinzii, with even breeding birds taking only small quantities of invertebrates, which suggests an adaptation to permit nesting in semi-arid areas and during periods of drought (1 Kear, J., Editor (2005). Ducks, Geese and Swans. Volume 1: General chapters, and Species accounts (Anhima to Salvadorina). Oxford University Press, Oxford, UK. Close ), while in Malawi stomach contents of four birds contained mainly seeds, especially those of Sacciolepis africana (3 Dowsett-Lemaire, F., and R. J. Dowsett (2006). The Birds of Malawi: An Atlas and Handbook. Tauraco Press & Aves, Liège, Belgium. Close ). Feeds by dabbling , head-dipping and upending in shallow waters; grazes on land and visits fields of stubble; frequently forages nocturnally on arable crops (1 Kear, J., Editor (2005). Ducks, Geese and Swans. Volume 1: General chapters, and Species accounts (Anhima to Salvadorina). Oxford University Press, Oxford, UK. Close ). Also visits cattle feedlots, at least in South Africa (13 van Niekerk, J. H. (2010). Assemblages and movements of waterfowl at cattle feedlots across Gauteng, South Africa. Ostrich 81(1):31–37. Close ). Usually feeds in pairs or small groups, but can gather into large flocks, sometimes thousands strong, in non-breeding season and readily congregates with other ducks (1 Kear, J., Editor (2005). Ducks, Geese and Swans. Volume 1: General chapters, and Species accounts (Anhima to Salvadorina). Oxford University Press, Oxford, UK. Close ).

Considered to be generally quiet, except during courtship, with male giving soft, whistle-like “whizzt” and rapid “geeeee”, and female a sharp “quack”, sometimes in quiet series (1 Kear, J., Editor (2005). Ducks, Geese and Swans. Volume 1: General chapters, and Species accounts (Anhima to Salvadorina). Oxford University Press, Oxford, UK. Close ), as well as a trembling “gueggeggeggegge” when inciting male to copulate (7 Brown, L. H., E. K. Urban, and K. Newman (1982). The Birds of Africa. Volume 1. Academic Press, London, UK and New York, USA. Close ); female vocalizations generally considered to be similar to those of same-sex Anas undulata (7 Brown, L. H., E. K. Urban, and K. Newman (1982). The Birds of Africa. Volume 1. Academic Press, London, UK and New York, USA. Close ).

Season variable, generally during rains: Jun–Nov (especially Oct–Nov during rains) in SW Cape, Nov–May (peak Apr) in Transvaal, Dec and Mar in Botswana, Jan in Namibia, all months except Oct and Dec (peak Jan–Apr during rains) in Zimbabwe (7 Brown, L. H., E. K. Urban, and K. Newman (1982). The Birds of Africa. Volume 1. Academic Press, London, UK and New York, USA. Close ), Dec–Jun (peak Jan–Feb during rains) in Zambia (6 Dowsett, R. J., D. R. Aspinwall, and F. Dowsett-Lemaire (2008). The Birds of Zambia. Tauraco Press & Aves, Liège, Belgium. Close ), Jan–Feb and Jun in Malawi (3 Dowsett-Lemaire, F., and R. J. Dowsett (2006). The Birds of Malawi: An Atlas and Handbook. Tauraco Press & Aves, Liège, Belgium. Close ), Mar–May (following rains) in Tanzania, Jan–Aug (following main rains) in Kenya (7 Brown, L. H., E. K. Urban, and K. Newman (1982). The Birds of Africa. Volume 1. Academic Press, London, UK and New York, USA. Close ), Sept in Ethiopia (4 Ash, J. S., and J. Atkins (2009). Birds of Ethiopia and Eritrea: An Atlas of Distribution. Christopher Helm, London, UK. Close ), Dec in Somalia (9 Ash, J. S., and J. E. Miskell (1998). Birds of Somalia. Pica Press, Robertsbridge, UK. Close ) and Dec and Feb–Jul (wet season) in Madagascar (2 Safford, R. J., and A. F. A. Hawkins, Editors (2013). The Birds of Africa. Volume 8. The Malagasy Region. Christopher Helm, London, UK. Close ). Monogamous pair-bond may be either long- or short-term (7 Brown, L. H., E. K. Urban, and K. Newman (1982). The Birds of Africa. Volume 1. Academic Press, London, UK and New York, USA. Close ). In single pairs; nest is mound of grass lined with down constructed by female (7 Brown, L. H., E. K. Urban, and K. Newman (1982). The Birds of Africa. Volume 1. Academic Press, London, UK and New York, USA. Close ), 153–177 mm wide by 64–102 mm deep (7 Brown, L. H., E. K. Urban, and K. Newman (1982). The Birds of Africa. Volume 1. Academic Press, London, UK and New York, USA. Close ), on ground among dense vegetation such as lush grass, rushes, reeds and other herbage, always near water (though can be up to 200 m away) (2 Safford, R. J., and A. F. A. Hawkins, Editors (2013). The Birds of Africa. Volume 8. The Malagasy Region. Christopher Helm, London, UK. Close ). Clutch 5–13 (4 Ash, J. S., and J. Atkins (2009). Birds of Ethiopia and Eritrea: An Atlas of Distribution. Christopher Helm, London, UK. Close ) (mean ten) buff- or cream-coloured eggs, laid at 24-hour intervals, size 46–54·1 mm × 35·1–41 mm, mass 36–40 g (7 Brown, L. H., E. K. Urban, and K. Newman (1982). The Birds of Africa. Volume 1. Academic Press, London, UK and New York, USA. Close ); incubation 25–28 days, by female alone guarded by male, commencing on completion of clutch (7 Brown, L. H., E. K. Urban, and K. Newman (1982). The Birds of Africa. Volume 1. Academic Press, London, UK and New York, USA. Close ); chicks  have dark brown down above  , pale yellowish below and on cheeks, with well-defined eyestripe, yellow supercilium and dark ear-coverts, with mean weight on hatching 23·5 g (captivity) (1 Kear, J., Editor (2005). Ducks, Geese and Swans. Volume 1: General chapters, and Species accounts (Anhima to Salvadorina). Oxford University Press, Oxford, UK. Close ); fledging c. 8 weeks, with male sometimes accompanying female in defending brood (1 Kear, J., Editor (2005). Ducks, Geese and Swans. Volume 1: General chapters, and Species accounts (Anhima to Salvadorina). Oxford University Press, Oxford, UK. Close ). Mean brood size in South Africa 7·2 young at up to one week after hatching and 5·9 young at 1–3 weeks (7 Brown, L. H., E. K. Urban, and K. Newman (1982). The Birds of Africa. Volume 1. Academic Press, London, UK and New York, USA. Close ). Probably breeds at age one year (1 Kear, J., Editor (2005). Ducks, Geese and Swans. Volume 1: General chapters, and Species accounts (Anhima to Salvadorina). Oxford University Press, Oxford, UK. Close ), with longevity record of 24 years (6 Dowsett, R. J., D. R. Aspinwall, and F. Dowsett-Lemaire (2008). The Birds of Zambia. Tauraco Press & Aves, Liège, Belgium. Close ).

Not globally threatened (Least Concern). Common to abundant; population appears stable, with estimates from late 1990s of 500,000–1,000,000 birds in S Africa, 100,000–300,000 in E Africa and just 15,000–25,000 birds in Madagascar (where largest concentrations number just hundreds and is commonest in W, S and on plateau) (2 Safford, R. J., and A. F. A. Hawkins, Editors (2013). The Birds of Africa. Volume 8. The Malagasy Region. Christopher Helm, London, UK. Close ); latter population is apparently declining due to habitat modification and loss (1 Kear, J., Editor (2005). Ducks, Geese and Swans. Volume 1: General chapters, and Species accounts (Anhima to Salvadorina). Oxford University Press, Oxford, UK. Close ), with latest estimate (2006) of just 5000–10,000 individuals (2 Safford, R. J., and A. F. A. Hawkins, Editors (2013). The Birds of Africa. Volume 8. The Malagasy Region. Christopher Helm, London, UK. Close ). In S of continent, considered most abundant duck; up to 500,000 estimated on Ngami L, Botswana; 29,000 in 1971 in Kafue Flats, Zambia. In Madagascar, uncommon in E, but one of most common ducks in rest of island. Is a favourite quarry species, and is hunted abundantly, with this species forming a significant part of the estimated 41,600 ducks shot and (mainly) snared on Chilwa floodplain of Malawi in 1998/99 season (which includes the species’ local breeding period) (3 Dowsett-Lemaire, F., and R. J. Dowsett (2006). The Birds of Malawi: An Atlas and Handbook. Tauraco Press & Aves, Liège, Belgium. Close ); also heavily hunted in Madagascar, especially in rice-growing areas (2 Safford, R. J., and A. F. A. Hawkins, Editors (2013). The Birds of Africa. Volume 8. The Malagasy Region. Christopher Helm, London, UK. Close ).