Chauna chavaria 

Scope: Global
Language: English

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Taxonomy [top]

Kingdom Phylum Class Order Family
Animalia Chordata Aves Anseriformes Anhimidae

Scientific Name: Chauna chavaria (Linnaeus, 1766)
Common Name(s):
English Northern Screamer
Taxonomic Source(s): SACC. 2005 and updates. A classification of the bird species of South America. Available at: #
Identification information: 76-91 cm. Huge and heavy-bodied peculiar goose-like bird. Distinctive head pattern, with grey crown and shaggy crest. Broad white "chinstrap" across throat and sides of face, and black neck. Otherwise dull with grey underparts and dark glossed green upperparts. Sharp spurs on bend of wing. Very large reddish-pink legs, with unwebbed feet. Voice One of the loudest birds in the world, with powerful bugled klerr-a-ruk, cherio.

Assessment Information [top]

Red List Category & Criteria: Near Threatened ver 3.1
Year Published: 2016
Date Assessed: 2016-10-01
Assessor(s): BirdLife International
Reviewer(s): Butchart, S. & Symes, A.
Contributor(s): Cuervo, A., Salaman, P., Sharpe, C J, Diaz-Jaramillo, C., Stiles, F., Cortés, O., Ruiz, C. & Donegan, T.
Facilitator/Compiler(s): Benstead, P., Capper, D., Isherwood, I., Pilgrim, J., Sharpe, C J, Stuart, T., Symes, A. & Ashpole, J
This species qualifies as Near Threatened because it has a moderately small and declining population; it almost meets the requirements for listing as threatened under criterion C2a(i).

Previously published Red List assessments:

Geographic Range [top]

Range Description:This species occurs in north-west Venezuela (around Lago Maracaibo in Zuila, Mérida and Trujillo) (Meyer de Schauensee and Phelps 1978) and north Colombia (from the lower Atrato valley east to the Ciénaga Grande de Santa Marta and the Cesar valley, and south in the middle Magdalena valley to south Bolívar) (Hilty and Brown 1986). The upper Cauca valley holds a tiny, isolated and apparently declining population (Naranjo 1986). Numbers had been estimated at c.2,000 individuals in Venezuela but are now thought to be <1,000, possibly as small as the low hundreds (C. J. Sharpe in litt. 2015). The total population has been estimated at 3,000-5,000 individuals (Callaghan in prep.). However, this may under-estimate the Colombian population, with c.5,000 or more birds perhaps a more accurate guess (Rodríguez and Rojas-Suárez 1995). The global population is estimated to be 2,500-9,999 individuals.

Countries occurrence:
Colombia; Venezuela, Bolivarian Republic of
Additional data:
Continuing decline in area of occupancy (AOO):Unknown
Extreme fluctuations in area of occupancy (AOO):NoEstimated extent of occurrence (EOO) - km2:297000
Continuing decline in extent of occurrence (EOO):UnknownExtreme fluctuations in extent of occurrence (EOO):No
Continuing decline in number of locations:Unknown
Extreme fluctuations in the number of locations:No
Upper elevation limit (metres):1200
Range Map:Click here to open the map viewer and explore range.

Population [top]

Population:The population estimate of 2,500-9,999 individuals is derived from P. G. W. Salaman in litt. (1999). This equates to 1,667-6,666 mature individuals, rounded here to 1,500-7,000 mature individuals. The population in Venezuela has been recently estimated at approximately <1,000 individuals (C. J. Sharpe in litt. 2015).

Trend Justification:  A slow and on-going population decline is suspected owing to habitat loss and possibly egg-collecting and hunting.
Current Population Trend:Decreasing
Additional data:
Number of mature individuals:1500-7000Continuing decline of mature individuals:Unknown
Extreme fluctuations:NoPopulation severely fragmented:No
Continuing decline in subpopulations:Unknown
Extreme fluctuations in subpopulations:NoAll individuals in one subpopulation:No

Habitat and Ecology [top]

Habitat and Ecology:This species is restricted to lowland marshes, swamps, lagoons, the banks of slow-flowing rivers and seasonally flooded alluvial plains, often in areas surrounded by forest (del Hoyo et al. 1992). It is exclusively vegetarian, grazing the green parts of succulent aquatic plants (del Hoyo et al. 1992), although digging for unknown food items is regular (Naranjo 1986). The nest is a large mass of marsh vegetation built up from the water, and 2-7 eggs are laid mostly in October to November, but breeding continues throughout the year (del Hoyo et al. 1992). Home ranges of pairs and family groups in Valle del Cauca averaged 0.11 km2 on the edge of a lagoon (Naranjo 1986).

Continuing decline in area, extent and/or quality of habitat:Unknown
Generation Length (years):5
Movement patterns:Not a Migrant
Congregatory:Congregatory (and dispersive)

Threats [top]

Major Threat(s): Loss of habitat owing to drainage of wetlands for cattle and agriculture is probably resulting in slow population declines (Callaghan in prep., Naranjo 1986), but is unlikely to affect seasonally flooded and deeper wetlands in the near future (P. G. W. Salaman in litt. 1999). Collection of eggs (A. Cuervo in litt. 1999), capture as pets (P. G. W. Salaman in litt. 1999, T. Donegan in litt. 2012, C. Ruiz in litt. 2012) and possibly illegal hunting in some areas, are unquantified threats (Callaghan in prep., C. Ruiz in litt. 2012). Construction of a pipeline and road through the wetlands of the Ciénaga Grande de Santa Marta and Isla de Salamanca in the mid-1970s obstructed tidal flow and caused extensive mangrove die-back, continuing until at least 1992 (Wege and Long 1995). In the same area, there is domestic and industrial pollution and sewage, urbanisation and mangrove cutting. Hydroelectric schemes alter hydrological regimes which may impact on the species's habitat in some places.

Conservation Actions [top]

Conservation Actions: Conservation and Research Actions Underway
It occurs in Salamanca National Park and Ciénaga Grande de Santa Marta Flora and Fauna Sanctuary, Magdalena, Colombia, but these areas have now lost sizeable areas of habitat (Callaghan in prep., Wege and Long 1995). Other less damaged protected areas include Los Katios National Park, Chocó, Colombia (P. G. W. Salaman in litt. 1999) and Ciénagas de Juan Manuel, Aguas Blancas y Aguas Negras Faunal Reserve, Zulia, Venezuela (Rodríguez and Rojas-Suárez 1995, C. J. Sharpe, J. P. Rodríguez and F. Rojas-Suárez in litt. 1999)

Conservation and Research Actions Proposed
Census and monitor populations to assess the global population and demographic trends and to refine the distribution and locate strongholds (Rodríguez and Rojas-Suárez 1995, P. G. W. Salaman in litt. 1999, C. J. Sharpe, J. P. Rodríguez and F. Rojas-Suárez in litt. 1999). Investigate its ecology, threats and conservation requirements (Rodríguez and Rojas-Suárez 1995, C. J. Sharpe, J. P. Rodríguez and F. Rojas-Suárez in litt. 1999). Improve the management of protected areas that are suffering encroachment and degradation. Increase the area of suitable habitat that has protected status. Control pollution in the species's habitats. Raise awareness of the species and its status in an effort to reduce persecution.

Citation: BirdLife International. 2016. Chauna chavaria. The IUCN Red List of Threatened Species 2016: e.T22679726A92826428. . Downloaded on 15 August 2018.
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