Yellow-knobbed curassow (Crax daubentoni)

Spanish:	Pavón Porú

Kingdom	Animalia
Phylum	Chordata
Class	Aves
Order	Galliformes
Family	Cracidae
Genus	Crax (1)
Size	Length: 84 – 92.5 cm (2)

Classified as Near Threatened (NT) on the IUCN Red List (1), and listed on Appendix III of CITES in Colombia (3).

The most striking features of this large forest bird are its crest of forward-curling feathers and the fleshy yellow knob and wattles at the base of its bill, for which the species earns its common name (4). Like other curassows, the male’s plumage is predominantly black, with a snow white lower abdomen and under-tail coverts. The tail feathers are also broadly tipped in white, except for the central pair that remains black (5). The sexes are similar in appearance, but the female lacks the yellow cere of the male, and has barring on its breast and upper belly. The female yellow-knobbed curassow is also the only female Crax species with a dark cere and pure white abdomen (2).

Restricted to north Venezuela (north of the Río Orinoco) and a few scattered localities in adjacent parts of north-east Colombia (2) (6) (7).

This bird is most commonly found in gallery forests of Venezuelan and Colombian llanos, but also in lowland deciduous and evergreen forest, especially in valleys and ravines near rivers (2) (6). These large forest birds also congregate by remaining water courses and water-holes in llanos during the dry season (2). The yellow-knobbed curassow has been recorded from foothills up to 800 metres above sea level in Venezuela and from 500 to 1,500 metres in Colombia (6).

This territorial curassow has a polygynous mating system (2), particularly when resources are abundant and less time needs to be spent on defending territories and more time can be invested in mating with multiple females (8). Unlike most gamebirds, curassows nest off the ground, with both males and females helping in the nest’s construction (4). Females lay between one and three eggs per clutch (9), with egg-laying having been recorded in May and June in Venezuela (2) (9), during the early rains, and in May in Colombia (2). This brood size is very small compared to those of many ground-nesting gamebirds (4).

Like other curassows, the yellow-knobbed curassow feeds mainly on the ground, although it will fly up into the trees if threatened (4). Foraging usually takes place in small family groups, but flocks of up to 25 birds may occur during the dry season (2) (9).

This striking forest bird is becoming increasingly threatened, with each of the now disjunct, isolated sub-populations undergoing a serious decline (7). Agricultural expansion has fragmented gallery forests, with many parts of the llanos having already been converted to rice fields (6). However, a more serious threat comes from the heavy hunting pressure on the species for food and sport, even in national parks and reserves (6) (7). Indeed, in Venezuela, the bountiful fauna of protected areas is particularly targeted by local hunting groups (6).

The yellow-knobbed curassow’s listing on Appendix III of the Convention on International Trade in Endangered Species (CITES) in Colombia confers a degree of protection by limiting the legal trade in this species across the country’s borders (3). This large forest bird also occurs in a number of protected areas, but protection against poaching is often inadequately enforced (6). Thus, more must be done to prevent hunting within these areas, which are supposed to provide safe refuge to the endangered species they house.

For more information on the yellow-knobbed curassow see:

• del Hoyo, J., Elliot, A. and Sargatal, J. (1992) Handbook of Birds of the World. Volume 2: New World Vultures to Guineafowl. Lynx Edicions, Barcelona.

For more information on this and other bird species please see:

• BirdLife International:
  http://www.birdlife.org

Authenticated (17/10/08) by MSc. John Kvarnbäck, ornithologist and birdguide.
jkvarn@gmail.com

• Cere: in birds, an area of skin at the base of the upper mandible surrounding the nostrils.
• Coverts: small feathers concealing the bases of larger primary feathers, particularly on the wings and tail.
• Llano: A large, grassy, almost treeless plain, especially one in Latin America.
• Polygyny: in animals, a pattern of mating in which a male has more than one female partner.
• Territorial: an animal, a pair of animals or a colony that occupies and defends an area.
• Territory: an area occupied and defended by an animal, a pair of animals or a colony.
• Wattles: bare fleshy skin that hangs from the bill, throat or eye of birds.

1. IUCN Red List (September, 2008)
   http://www.iucnredlist.org
2. del Hoyo, J., Elliot, A. and Sargatal, J. (1992) Handbook of Birds of the World. Volume 2: New World Vultures to Guineafowl. Lynx Edicions, Barcelona.
3. CITES (May, 2006)
   http://www.cites.org
4. Burnie, D. (2001) Animal: The Definitive Visual Guide to the World's Wildlife. Dorling Kindersley, London.
5. Vaurie, C. (1967) Systematic Notes on the Bird Family Cracidae. No. 9. The Genus Crax. American Museum Novitates, 2305: 2 - 20. Available at:
   http://digitallibrary.amnh.org/dspace/bitstream/2246/3508/1/N2305.pdf
6. BirdLife International (May, 2006)
   http://www.birdlife.org/datazone/species/index.html?action=SpcHTMDetails.asp&sid=105&m=0
7. Zoological Museum of the University of Amsterdam (May, 2006)
   http://ip30.eti.uva.nl/zma3d/detail.php?id=112&type=family&sort=taxon
8. Garcia, C. and Brooks, D.M. (1997) Evolution of Crax sociobiology and phylogeny using behavioral and ecological characters. In: Strahl, S.D., Beaujon, S., Brooks, D.M., Begazo, A., Sedaghatkish, G. and Olmos, F. (Eds) Cracidae: their Biology and Conservation. Hancock House Publishers, WA.
9. Kvarnbäck, J. (2008) Pers. comm.