Dusky-legged Guan Penelope obscura Scientific name definitions

The Dusky-legged Guan is fairly common in forest, including edge habitats and scrub, both in lowland and montane areas. The most southerly distributed of the cracids, this species has two subspecies: one in southeastern Brazil (P. o. bronzina), and one in southern Brazil, southeastern Paraguay, Uruguay, and northeastern Argentina (P. o. obscura). While it resembles other Penelope guans, the Dusky-legged Guan co-occurs only with the much smaller Rusty-margined Guan (P. superciliaris). Like other members of the genus, it forages largely in trees, sometimes in fairly large groups at fruiting trees. Flight displays are given frequently at dawn, and include rapid wing-drumming that can be heard for a great distance.

Dark legs; overall plumage and bare facial skin also dark. Sexes alike, except that iris is red in male , pale brown in female (1 del Hoyo, J., and A. Motis (2004). Update chapter. In Curassows and Related Birds (J. Delacour, and D. Amadon), Second edition. Lynx Edicions, Barcelona, Spain, and American Museum of Natural History, New York, USA. pp. 322–476. Close ); however, some variation (perhaps age-related) noted at least in subspecies bronzina (1 del Hoyo, J., and A. Motis (2004). Update chapter. In Curassows and Related Birds (J. Delacour, and D. Amadon), Second edition. Lynx Edicions, Barcelona, Spain, and American Museum of Natural History, New York, USA. pp. 322–476. Close ). Juvenile  smaller than adult at c. 40 days, with white throat but no white flecking above; by 90 days plumage and size basically as adult (1 del Hoyo, J., and A. Motis (2004). Update chapter. In Curassows and Related Birds (J. Delacour, and D. Amadon), Second edition. Lynx Edicions, Barcelona, Spain, and American Museum of Natural History, New York, USA. pp. 322–476. Close ).

Most likely to be confused with Rusty-margined Guan (P. superciliaris) (1 del Hoyo, J., and A. Motis (2004). Update chapter. In Curassows and Related Birds (J. Delacour, and D. Amadon), Second edition. Lynx Edicions, Barcelona, Spain, and American Museum of Natural History, New York, USA. pp. 322–476. Close ), at least in parts of Argentina and southeastern Brazil, but they are usually not syntopic, except perhaps seasonally or very locally (1 del Hoyo, J., and A. Motis (2004). Update chapter. In Curassows and Related Birds (J. Delacour, and D. Amadon), Second edition. Lynx Edicions, Barcelona, Spain, and American Museum of Natural History, New York, USA. pp. 322–476. Close ), with smaller P. superciliaris largely restricted to drier forests, well-wooded savannas, and restinga (2 Guix, J.C. (1997). Exclusão geográfica e ecológica de Penelope obscura, Penelope superciliaris e Pipile jacutinga (Galliformes, Cracidae) no estado de São Paulo. Ararajuba. 5(2): 195–202. Close ). Rusty-margined Guan has gray scalloping on foreneck and breast (as compared to white streaking in obscura) and an unmarked mantle (streaked white in obscura) (1 del Hoyo, J., and A. Motis (2004). Update chapter. In Curassows and Related Birds (J. Delacour, and D. Amadon), Second edition. Lynx Edicions, Barcelona, Spain, and American Museum of Natural History, New York, USA. pp. 322–476. Close ).

Does occur syntopically with Black-fronted Piping-Guan (Pipile jacutinga), but the latter is much larger with white on head and in wings.

Formerly conspecific with Yungas Guan (P. bridgesi), but differences in size, plumage, vocalizations, and complete allopatry (3 Evangelista-Vargas, O.D. and Silveira, L.F. (2018). Morphological evidence for the taxonomic status of the Bridge’s Guan, Penelope bridgesi, with comments on the validity of P. obscura bronzina (Aves: Cracidae). Zoologia. 35: e12993. Close ) have led to the latter's recognition as a full species (4 Remsen, J. V., Jr., J. I. Areta, E. Bonaccorso, S. Claramunt, A. Jaramillo, D. F. Lane, J. F. Pacheco, M. B. Robbins, F. G. Stiles, and K. J. Zimmer (2021). A classification of the bird species of South America. Version 15. American Ornithological Society. Close ). Has also been considered conspecific with Spix's Guan (P. jacquacu), but tracheal morphology is different. Potential contact between nominate and bronzina in southern Brazil and possibly also extreme northeastern Argentina requires detailed study, but a recent morphological study has suggested that the latter cannot be recognized (3 Evangelista-Vargas, O.D. and Silveira, L.F. (2018). Morphological evidence for the taxonomic status of the Bridge’s Guan, Penelope bridgesi, with comments on the validity of P. obscura bronzina (Aves: Cracidae). Zoologia. 35: e12993. Close ).

Subspecies vary in size, tone of general coloration, and markings; nominate is darkest and smallest, with well-developed whitish streaks only on foreneck and breast; subspecies <em>bronzina</em> has more conspicuous white edges on feathers of head , forming well-developed supercilium.

Two subspecies recognized.

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SUBSPECIES

Penelope obscura bronzina Scientific name definitions

Distribution

E Brazil (E Minas Gerais S to Santa Catarina; recorded also in S Bahia (5 Souza, D.G.S. (1999). Novos registros de espécies de aves no estado da Bahia e sua correlação com os ecossistemas. Atualidades Orn. 88: 6–7. In Portuguese. Close ) ); perhaps NE Argentina (Misiones).

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SUBSPECIES

Penelope obscura obscura Scientific name definitions

Distribution

SE Paraguay (6 Smith, P. and Derna, R. (2015). On the status of Dusky-legged Guan Penelope obscura Temminck, 1815 (Aves: Cracidae) in Paraguay. Pap. Avuls. Dept. Zool. São Paulo. 55(14): 211–216. Close ), NE Argentina (NE Buenos Aires, SE Entre Randiacute;os, SC Corrientes; records from Misiones may refer to bronzina), Uruguay and extreme S Brazil (Rio Grande do Sul, but perhaps also in Santa Catarina and Paranandaacute;) (7 del Hoyo, J., and A. Motis (2004). Update chapter. Pp. 322–476 in: J. Delacour, and D. Amadon (2004). Curassows and Related Birds. 2nd edition. Lynx & The American Museum of Natural History, Barcelona & New York. Close ).

Formerly conspecific with P. bridgesi. Has been considered closely related to P. jacquacu, with which it was also formerly conspecific. In a recent molecular phylogeny, however, P. obscura was found to be sister to a small clade of guans that included P. jacucaca, P. pileata, and P. ochrogaster. It was found to be more distantly related to other species, which formed another clade (8 Hosner, P. A., E. L. Braun, and R. T. Kimball (2016). Rapid and recent diversification of curassows, guans, and chachalacas (Galliformes: Cracidae) out of Mesoamerica: Phylogeny inferred from mitochondrial, intron, and ultraconserved element sequences. Molecular Phylogenetics and Evolution 102:320-330 Close ). In this phylogeny, P. bridgesi was not sampled.

Penelope obscura bronzina. Eastern Brazil (eastern Minas Gerais south to Santa Catarina; recorded also in south Bahia (5 Souza, D.G.S. (1999). Novos registros de espécies de aves no estado da Bahia e sua correlação com os ecossistemas. Atualidades Orn. 88: 6–7. In Portuguese. Close ); perhaps northeastern Argentina (Misiones).

Penelope obscura obscura. Southeastern Paraguay (6 Smith, P. and Derna, R. (2015). On the status of Dusky-legged Guan Penelope obscura Temminck, 1815 (Aves: Cracidae) in Paraguay. Pap. Avuls. Dept. Zool. São Paulo. 55(14): 211–216. Close ), northeastern Argentina (northeastern Buenos Aires, southeastern Entre Ríos, south-central Corrientes; records from Misiones may refer to bronzina), Uruguay and extreme southern Brazil (Rio Grande do Sul, but perhaps also in Santa Catarina and Paraná) (1 del Hoyo, J., and A. Motis (2004). Update chapter. In Curassows and Related Birds (J. Delacour, and D. Amadon), Second edition. Lynx Edicions, Barcelona, Spain, and American Museum of Natural History, New York, USA. pp. 322–476. Close ).

Tall forest, gallery forest (to which subspecies obscura is closely tied) (1 del Hoyo, J., and A. Motis (2004). Update chapter. In Curassows and Related Birds (J. Delacour, and D. Amadon), Second edition. Lynx Edicions, Barcelona, Spain, and American Museum of Natural History, New York, USA. pp. 322–476. Close ), small river islands with secondary forest, and mature plantations surrounded by grassland, woodland patches, and second growth in lowlands and foothills of tropical and upper tropical zones; also montane forest up to 2300 m (1 del Hoyo, J., and A. Motis (2004). Update chapter. In Curassows and Related Birds (J. Delacour, and D. Amadon), Second edition. Lynx Edicions, Barcelona, Spain, and American Museum of Natural History, New York, USA. pp. 322–476. Close ), where lower country is too dry for evergreen forest, or forest has been cleared; sometimes ventures into scrub and agricultural land (including plantations) (1 del Hoyo, J., and A. Motis (2004). Update chapter. In Curassows and Related Birds (J. Delacour, and D. Amadon), Second edition. Lynx Edicions, Barcelona, Spain, and American Museum of Natural History, New York, USA. pp. 322–476. Close ). Recorded locally from sea-level (1 del Hoyo, J., and A. Motis (2004). Update chapter. In Curassows and Related Birds (J. Delacour, and D. Amadon), Second edition. Lynx Edicions, Barcelona, Spain, and American Museum of Natural History, New York, USA. pp. 322–476. Close ). Subspecies <em>bronzina</em> occurs in Araucaria forest, but prefers Atlantic forest (2 Guix, J.C. (1997). Exclusão geográfica e ecológica de Penelope obscura, Penelope superciliaris e Pipile jacutinga (Galliformes, Cracidae) no estado de São Paulo. Ararajuba. 5(2): 195–202. Close ). May be scarce in densest forests, perhaps due to abundance of mammalian predators and preference for feeding on ground.

Presumably largely sedentary, but in southern São Paulo, southeastern Brazil (bronzina), evidence suggests that some birds descend between November and February to take advantage of many Myrtaceae spp. fruiting at lower elevations (1 del Hoyo, J., and A. Motis (2004). Update chapter. In Curassows and Related Birds (J. Delacour, and D. Amadon), Second edition. Lynx Edicions, Barcelona, Spain, and American Museum of Natural History, New York, USA. pp. 322–476. Close ). No further information available.

Main Foods Taken

Fruits.

Food Capture and Consumption

Forages singly, in pairs or in small parties, usually of up to eight birds (1 del Hoyo, J., and A. Motis (2004). Update chapter. In Curassows and Related Birds (J. Delacour, and D. Amadon), Second edition. Lynx Edicions, Barcelona, Spain, and American Museum of Natural History, New York, USA. pp. 322–476. Close ), although as many as 30 recorded; larger gatherings especially prevalent in winter or in places where food put out for the birds (1 del Hoyo, J., and A. Motis (2004). Update chapter. In Curassows and Related Birds (J. Delacour, and D. Amadon), Second edition. Lynx Edicions, Barcelona, Spain, and American Museum of Natural History, New York, USA. pp. 322–476. Close ); mainly in trees, especially in lower and middle storeys, but often on ground. Ground-feeding apparently most prevalent in winter, at least in some parts of range (1 del Hoyo, J., and A. Motis (2004). Update chapter. In Curassows and Related Birds (J. Delacour, and D. Amadon), Second edition. Lynx Edicions, Barcelona, Spain, and American Museum of Natural History, New York, USA. pp. 322–476. Close ).

Major Food Items

Fruits , including those of Eugenia uruguayensis (Myrtaceae), Citharexylum montevidense (Verbenaceae), Rapanea lorentziana (Myrsinaceae), Didymopanax (Araliaceae), Calyptranthes (Myrtaceae) and Croton (Euphorbiaceae), but many others recorded, including Cecropia sp. (9 Vasconcelos, M. F., and T. A. Melo-Júnior (2001). An ornithological survey of Serra do Caraça, Minas Gerais, Brazil. Cotinga 15:21–31. Close ) and Miconia chartacea (10 Parrini, R., and J. F. Pacheco (2011). Frugivoria por aves em seis espécies arbóreas do gênero Miconia (Melastomataceae) na Mata Atlântica do Parque Nacional da Serra dos Órgãos, Região Sudeste do Brasil. Atualidades Ornitológicas 159:51–58. Close ); also those of certain palms, which are apparently favourite food in Paraguay; recorded invading poultry yards to feed on corn in Rio Grande do Sul; study in São Paulo suggests species is rather specialized frugivore, preferring ripe Myrtaceae fruits up to 32 mm in diameter above those of most other families, e.g., Lauraceae (1 del Hoyo, J., and A. Motis (2004). Update chapter. In Curassows and Related Birds (J. Delacour, and D. Amadon), Second edition. Lynx Edicions, Barcelona, Spain, and American Museum of Natural History, New York, USA. pp. 322–476. Close ). In northeastern Argentina, winter diet heavily dependent on two species of introduced privets, Ligustrum sinense (especially) and L. lucidum (Oleaceae) (11 Merler, J.A., Diuk-Wasser, M.A. and Quintana, R.D. (2001). Winter diet of Dusky-legged Guan (Penelope obscura) at the Paraná River Delta region. Studies on Neotropical Fauna and Environment. 36(1): 33–38. Close ).

Quantitative Analysis

Overall diet believed to comprise c. 77% fruits, 16·7% leaves and 6·3% flowers (12 Muñoz, M.C. and Kattan, G.H. (2007). Diets of cracids: how much do we know? Orn. Neotropical. 18(1): 21–36. Close ). In areas where food is supplied for the birds, e.g., in some protected areas, they move less, disperse 80% fewer species of plants and consume 30% fewer seeds, thus human food supply can interfere in the species’ behavior and richness of native seeds dispersed (13 Vasconcellos-Neto, J., Ramos, R.R. and Pinto, L.P. (2015). The impact of anthropogenic food supply on fruit consumption by dusky-legged guan (Penelope obscura Temminck, 1815): potential effects on seed dispersal in an Atlantic forest area. Braz. J. Biol.. 75(4): 1008–1017. Close ).

Males known to uncover food hidden on ground for their mates, sometimes even directly feeding the females (14 Sazima, I. (2015). Uncovering titbits for the ladies: Dusky-legged Guan males stomp out food for their females. Revista Brasileira de Ornitologia. 23(3): 315–318. Close ).

Drinking

Drinks at dawn at rivers, pools or forest streams.

Defecation

Found to defecate weevils alive when ingested within palm fruits (1 del Hoyo, J., and A. Motis (2004). Update chapter. In Curassows and Related Birds (J. Delacour, and D. Amadon), Second edition. Lynx Edicions, Barcelona, Spain, and American Museum of Natural History, New York, USA. pp. 322–476. Close ).

Vocalizations best described for bronzina.

Vocal Array

Loud, harsh “oaaaao” (example ) (with variants; example ) , more melodious rising calls  and a braying or slightly bark-like, repeated “wow” in alarm  (1 del Hoyo, J., and A. Motis (2004). Update chapter. In Curassows and Related Birds (J. Delacour, and D. Amadon), Second edition. Lynx Edicions, Barcelona, Spain, and American Museum of Natural History, New York, USA. pp. 322–476. Close ). In comparison, nominate obscura alarm calls are reportedly higher-pitched, disyllabic (1 del Hoyo, J., and A. Motis (2004). Update chapter. In Curassows and Related Birds (J. Delacour, and D. Amadon), Second edition. Lynx Edicions, Barcelona, Spain, and American Museum of Natural History, New York, USA. pp. 322–476. Close ).

In flight display, at dawn, both subspecies produce loud rattling wing noises interrupted by a pause midway (1 del Hoyo, J., and A. Motis (2004). Update chapter. In Curassows and Related Birds (J. Delacour, and D. Amadon), Second edition. Lynx Edicions, Barcelona, Spain, and American Museum of Natural History, New York, USA. pp. 322–476. Close ).

Courtship, Copulation, and Pair Bond

Display includes raising spread tail and inflating the red throat pouch.

In Brazil, one half-grown juvenile seen with adult in January in Rio Grande do Sul (obscura), pairs with chicks in early December and early January in Santa Catarina (bronzina) and other records of chicks (all bronzina) from September  (Espírito Santo), November (Rio de Janeiro  , externallink ) and December (Rio de Janeiro  , externallink ). Display recorded in southeastern Brazil in September (1 del Hoyo, J., and A. Motis (2004). Update chapter. In Curassows and Related Birds (J. Delacour, and D. Amadon), Second edition. Lynx Edicions, Barcelona, Spain, and American Museum of Natural History, New York, USA. pp. 322–476. Close ).

Nest is cup-like (c. 60 cm in diameter) (1 del Hoyo, J., and A. Motis (2004). Update chapter. In Curassows and Related Birds (J. Delacour, and D. Amadon), Second edition. Lynx Edicions, Barcelona, Spain, and American Museum of Natural History, New York, USA. pp. 322–476. Close ), or bowl-shaped (1 del Hoyo, J., and A. Motis (2004). Update chapter. In Curassows and Related Birds (J. Delacour, and D. Amadon), Second edition. Lynx Edicions, Barcelona, Spain, and American Museum of Natural History, New York, USA. pp. 322–476. Close ), constructed of twigs and stems, lined with leaves, sited in a tree, usually well hidden in dense tangle of vegetation, c. 3–10 m (1 del Hoyo, J., and A. Motis (2004). Update chapter. In Curassows and Related Birds (J. Delacour, and D. Amadon), Second edition. Lynx Edicions, Barcelona, Spain, and American Museum of Natural History, New York, USA. pp. 322–476. Close ) above ground; speculated to trample leaves or arboreal bromeliads to form platform for nest (1 del Hoyo, J., and A. Motis (2004). Update chapter. In Curassows and Related Birds (J. Delacour, and D. Amadon), Second edition. Lynx Edicions, Barcelona, Spain, and American Museum of Natural History, New York, USA. pp. 322–476. Close ).

Usually 2–3 cream-colored (1 del Hoyo, J., and A. Motis (2004). Update chapter. In Curassows and Related Birds (J. Delacour, and D. Amadon), Second edition. Lynx Edicions, Barcelona, Spain, and American Museum of Natural History, New York, USA. pp. 322–476. Close ) eggs (up to four), size 69–79·3 mm × 49·4–55·7 mm (1 del Hoyo, J., and A. Motis (2004). Update chapter. In Curassows and Related Birds (J. Delacour, and D. Amadon), Second edition. Lynx Edicions, Barcelona, Spain, and American Museum of Natural History, New York, USA. pp. 322–476. Close ).

Incubation c. 28 days; can lay two clutches in same year.

Older chick  dark above, with intricate reddish-brown, buff-and-black face markings, broad buff and black stripes over crown and nape, pale buff spotting on wings and tail, and creamy yellow underparts.

Not globally threatened (Least Concern). Subspecies bronzina has declined drastically in state of inlinemedia and is considered threatened in Minas Gerais, both Brazil, and was considered globally Vulnerable in 1990 by ICBP/IUCN International Cracidae Specialist Group; population placed at 5000–10,000 individuals, although this seems too low, given evidence of some local densities, and it is reasonably well protected within several conservation units, e.g., Itatiaia and Serra dos Órgãos National Parks, Rio Doce, Carlos Botelho and Intervales State Parks (where perhaps c. 650 individuals) (15 Guix, J.C., Mañosa, S., Pedrocchi, V., Vargas, M.J. and Souza, F.L. (1997). Census of three frugivorous birds in an Atlantic rainforest area of southeastern Brazil. Ardeola. 44(2): 229–233. Close ), and RPPN Serra do Caraça (1 del Hoyo, J., and A. Motis (2004). Update chapter. In Curassows and Related Birds (J. Delacour, and D. Amadon), Second edition. Lynx Edicions, Barcelona, Spain, and American Museum of Natural History, New York, USA. pp. 322–476. Close ). Nominate subspecies said to survive in substantial numbers in Uruguay, especially in dense woodlands of north; also in many areas of Rio Grande do Sul, Brazil, which has been considered as indication that illegal hunting for food or sport by locals is not a significant threat there; fairly common in several protected areas there, e.g., Aparados da Serra National Park, Rio Grande do Sul, and Iguaçu National Park, Paraná. Rare and local in Paraguay, with illegal hunting an ongoing problem (6 Smith, P. and Derna, R. (2015). On the status of Dusky-legged Guan Penelope obscura Temminck, 1815 (Aves: Cracidae) in Paraguay. Pap. Avuls. Dept. Zool. São Paulo. 55(14): 211–216. Close ). Recently reported to be local and generally scarce in NE Argentina, where common during 19th century; 4–5 pairs seen in 1985–1986 in Reserva El Bagual (Presidente Irigoyen), Formosa (but this sighting and others from E Chaco are strongly doubted) (1 del Hoyo, J., and A. Motis (2004). Update chapter. In Curassows and Related Birds (J. Delacour, and D. Amadon), Second edition. Lynx Edicions, Barcelona, Spain, and American Museum of Natural History, New York, USA. pp. 322–476. Close ), and minimum 30 birds estimated in c. 1000 ha of islands in Paraná Delta, Buenos Aires, where surrounding habitat is being rapidly deforested or converted into plantations (although some evidence that it can adapt to latter) (1 del Hoyo, J., and A. Motis (2004). Update chapter. In Curassows and Related Birds (J. Delacour, and D. Amadon), Second edition. Lynx Edicions, Barcelona, Spain, and American Museum of Natural History, New York, USA. pp. 322–476. Close ), and few recent records in Misiones (16 Bodrati, A. and Cockle, K. (2006). New records of rare and threatened birds from the Atlantic Forest of Misiones, Argentina. Cotinga. 26: 20–24. Close ); recently seen in secondary forest. Considered Vulnerable in Argentina by Dirección General de Fauna, and said to be decreasing in numbers except in a few national parks; intensively hunted for food and sport, despite legal protection. Kept and bred in captivity locally and in a few collections abroad.