Yellow-billed Teal Anas flavirostris Scientific name definitions

The Yellow-billed Teal is a common duck of southern South America.  The species shows the compact proportions typical of teal and is gray below and brown above with a dark brown head and yellow bill.  Overall Yellow-billed Teal look like a darker, smaller and less elegant version of the widely sympatric Yellow-billed Pintail.  Birds from the high altiplano are pale silvery below, whereas the lowland race is darker grayish brown.  In flight and when excited, males give a creaky "peeet" call and females quack, also typical of teal.

35–45 cm; 388–830 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 ). Head sometimes paler than in bird depicted. Both races resemble <em>A. georgica</em> , but always smaller, shorter-necked and darker-headed  . Male lacks eclipse plumage, has head and neck pale grey to buff, heavily spotted or vermiculated black, upperparts black and brownish, belly and sides grey to pale brown, spotted  darker on breast, uppertail-coverts and tail grey-brown, wings grey-brown on coverts, becoming darker on remiges, speculum  velvet black and metallic green, bordered in front by rufescent band and buff or white on trailing edge; bill yellow with black culmen and tip and pale grey to cream-coloured mandible, legs  and feet grey, and eyes brown. Female slightly smaller and duller, with scallops  (rather than spots) on breast and sides, and bill paler (at least in nominate) with brown culmen stripe (2 Wilson, R.E., Goldfeder, S. and McCracken, K.G. (2004). Bill sexual dichromatism of Yellow-billed Pintail (Anas georgica) and Speckled Teal (A. flavirostris). Ornitología Neotropical. 15(4): 543–545. Close ). Juvenile with duller yellow bill and spotting on underparts, while upperparts appear obscurely mottled. Subspecies vary in colour: <em>oxyptera</em> has dark markings limited to sides of breast, pale parts seem white from a distance, contrasting with dark head , and has slender dull yellow bill  .

Editor's Note: This article requires further editing work to merge existing content into the appropriate Subspecies sections. Please bear with us while this update takes place.

Editor's Note: Additional distribution information for this taxon can be found in the 'Subspecies' article above. In the future we will develop a range-wide distribution article.

Variety of freshwater lakes , rivers and marshes, generally at high altitude in mountainous country in bogs with ponds and creeks, but also in lower ground. In winter, commonly on coast. Race oxyptera principally occurs at 2500–4500 m (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 ).

Southernmost breeding birds winter in more temperate regions, as far N as Uruguay, Paraguay and SE Brazil  (Santa Catarina  , Aug 1988, Feb 199, Mar 1992 and several records in Mar 2003–Jan 2005, and Rio de Janeiro, Sept 1990) (3 Bornschein, M.R., Reinert, B.L. and Pichorim, M. (1997). Notas sobre algumas aves novas ou pouco conhecidas no sul do Brasil. Ararajuba. 5(1): 53–59. Close , 4 Sick, H. (1997). Ornitologia Brasileira. Editora Nova Fronteira, Rio de Janeiro, Brazil. Close , 5 Amorim, J.F. and Piacentini, V.Q. (2006). Novos registros de aves raras em Santa Catarina, Sul do Brasil, incluindo os primeiros registros documentados de algumas espécies para o Estado. Rev. Bras. Orn. 14(2): 145–149. Close ). Falkland Is and Andean populations mainly sedentary, the latter perhaps forced to descend to lower altitudes by adverse winter weather, e.g. reaching of Pacific lowlands of N Chile (Lluta Valley) and S Peru (Huasco Valley) (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 ). Has been recorded up to c. 90 km offshore from Patagonia in Sept (6 Seco Pon, J.P. and Bastida, J. (2015). Patos Barcino (Anas flavirostris), Capuchino (Anas versicolor), y Overo (Anas sibilatrix) en el sur del Océano Atlántico. Nuestras Aves. 60: 54–55. Close ).

Small aquatic invertebrates (insects, crustaceans, amphipods) and seeds, fruits and vegetative parts of aquatic plants (seaweed, algae). In Chile, in winter, stomach contents (race flavirostris) comprised 79% Potentilla anserina and 6·4% Trifolium, or 72·6% P. anserina and 5·9% Ranunculus by dry weight, while in summer stomachs of both young and adults contained cladocerans (Bosmina), midge larvae, insects, fish eggs, amphipods and seeds (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 ). Filters mud while walking along water's edge, or gathers food items by dabbling, head dipping or upending in shallow waters, and very occasionally diving (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 ).

Male gives loud, single-syllabled “krick” in display, alarm and when separated when female, as well as a similar whistled note in other displays, various chittering notes and soft, meow-like calls when agitated; female utters loud quack note in alarm, when separated from male or brood, and encourages male to mate with grating “rraak” and “Decrescendo” call has 5–12 syllables (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 ).

Season variable according to locality; season generally Oct–Mar in race oxyptera (with perhaps additional clutches in Jun–Jul in Peru for oxyptera) and Aug–Jan in nominate race (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 ). Monogamous with long-term pair-bonds (lasting up to six years), although extra-pair courtship is frequently observed in nominate race (7 Port, J.L. and McKinney, F. (2001). Behavioral adaptations for breeding in arboreal-nesting Speckled Teal. Wilson Bull.. 113(2): 177–188. Close ). In single pairs or loose groups, e.g. when using old parakeet cavities; nest typically well hidden, often among thick vegetation or in trees, near water, but also in cavities in banks or rocky outcrops (race oxyptera) or old ground burrows belonging to woodpeckers (probably Campo Flickers Colaptes campestris) or abandoned chambers of Monk Parakeet  (Myiopsitta monachus) (8 Eberhard, J.R. (1998). Breeding biology of the Monk Parakeet. Wilson Bull.. 110(4): 463–473. Close , 7 Port, J.L. and McKinney, F. (2001). Behavioral adaptations for breeding in arboreal-nesting Speckled Teal. Wilson Bull.. 113(2): 177–188. Close ), typically 5–20 m above ground in Celtis tala or Eucalyptus, and other tree nest-sites (race flavirostris) (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 ), including once in Nothofagus in S Chile, where species might compete with Slender-billed Parakeets (Enicognathus leptorhynchus) for suitable cavities (9 Jiménez, J.E. and White, T.H. (2011). Use of tree cavities for nesting by Speckled Teal (Anas flavirostris) in southern Chile: potential competition with the Slender-billed Parakeet (Enicognathus leptorhynchus). Ornitología Neotropical. 22(3): 465–469. Close ). In areas where ducks commonly use Myiopsitta monachus nests, inter- and intraspecific competition is intense, with parakeets aggressively defending occupied cavities, forcing teal to compete with each other for abandoned cavities, thus male teals assist their mates to obtain and defend sites against other pairs (7 Port, J.L. and McKinney, F. (2001). Behavioral adaptations for breeding in arboreal-nesting Speckled Teal. Wilson Bull.. 113(2): 177–188. Close ); teal sometimes attempt to nest in nest chambers already occupied by parakeets (10 Port, J.L. and Brewer, G.L. (2004). Use of Monk Parakeet (Myiopsitta monachus) nests by Speckled Teal (Anas flavirostris) in eastern Argentina. Ornitología Neotropical. 15(2): 209–218. Close ). High nest-site fidelity (63% in female and 56·3% in male) (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 ), and in Buenos Aires province, Argentina, 19 of 22 females returned to same nest-site in subsequent season (7 Port, J.L. and McKinney, F. (2001). Behavioral adaptations for breeding in arboreal-nesting Speckled Teal. Wilson Bull.. 113(2): 177–188. Close ). Clutch 5–13 dark cream eggs (once 18, involving two females laying in same cavity) (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 ), laid at 1–2·4-day intervals (in captivity), size 55·2–57·2 mm × 37·8–38·9 mm (oxyptera, in wild) (11 Salvador, S. A. (2015). Reproducción de aves andinas del noroeste argentino. Historia Natural 5(1):49–76. Close ), 59·9 mm × 38·3 mm (oxyptera, in captivity) or 52·1 mm × 36 mm (flavirostris), mass 40·9 g (oxyptera) or 36·5 g (flavirostris) (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 ); incubation c. 24–35 days by female alone (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 ); chicks have dark brown down above, yellowish below (whiter in Andean subspecies) with broad dark band on cheeks and mass of 22·1 g (flavirostris) or 24 g (oxyptera) at one day old (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 6–7 weeks, with young generally tended by both adults (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 ). Potential predators of ducklings in S of range include Southern Caracaras (Caracara plancus), Aplomado Falcons (Falco femoralis) and Peregrine Falcons (F. peregrinus) (7 Port, J.L. and McKinney, F. (2001). Behavioral adaptations for breeding in arboreal-nesting Speckled Teal. Wilson Bull.. 113(2): 177–188. Close ). Nest success 42·9% for nominate race, with nest desertion a common cause of failure (7 Port, J.L. and McKinney, F. (2001). Behavioral adaptations for breeding in arboreal-nesting Speckled Teal. Wilson Bull.. 113(2): 177–188. Close , 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 ), but those nesting in parakeet nests are safe from periodic flooding and from numerous terrestrial predators (10 Port, J.L. and Brewer, G.L. (2004). Use of Monk Parakeet (Myiopsitta monachus) nests by Speckled Teal (Anas flavirostris) in eastern Argentina. Ornitología Neotropical. 15(2): 209–218. Close ). Sexual maturity achieved at one year old (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 ).

Not globally threatened (Least Concern). Generally common, even locally abundant, with overall population of nominate race in mainland South America estimated at > 1,000,000 birds (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 ), plus an additional 6000–11,000 pairs (or 18,000–33,000 birds) in Falkand Is during breeding bird survey of 1983–1993 (12 Woods, R. W., and A. Woods (1997) Atlas of Breeding Birds of the Falkland Islands. Anthony Nelson, Oswestry, UK. Close ), and perhaps 25,000–100,000 for oxyptera (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 ). Nominate subspecies widespread within its range; common resident on Falkland Is . Partial counts in Jul 1990 yielded 3019 birds in Argentina, 884 in Chile and 678 in Uruguay. In Peru, in N Central Cordillera, 1000+ recorded at Laguna de los Cóndores (13 Mark, T., L. Augustine, J. Barrio, J. Flanagan, and W.-P. Vellinga (2008). New records of birds from the northern Cordillera Central of Peru in a historical perspective. Cotinga 29:108–125. Close ). Estimated 40–50 birds in Cumberland Bay, South Georgia, a small breeding population discovered in 1971 that probably originates from introduction by early whalers or immigration from Falklands, with a few records from offshore Bird I (14 Prince, P. A., and J. P. Croxall (1996). The birds of South Georgia. Bulletin of the British Ornithologists’ Club 116(2):81–104. Close ). Hunted intensely in winter quarters, but population does not seem seriously affected, and egg collecting, erosion from overgrazing and development are additional threats (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 ).