Data Zone
Justification of Red List category
This species has an extremely large range, and hence does not approach the thresholds for Vulnerable under the range size criterion (Extent of Occurrence under 20,000 km² combined with a declining or fluctuating range size, habitat extent/quality, or population size and a small number of locations or severe fragmentation). The population size may be moderately small to large, but it is not believed to approach the thresholds for Vulnerable under the population size criterion (under 10,000 mature individuals with a continuing decline estimated to be over 10% in ten years or three generations, or with a specified population structure). Despite the fact that the population trend appears to be decreasing, the decline is not believed to be sufficiently rapid to approach the thresholds for Vulnerable under the population trend criterion (over 30% decline over ten years or three generations). For these reasons the species is evaluated as Least Concern.
Population justification
The global population size is estimated at 25,000-100,000 individuals (Wetlands International 2023), which equates to 16,700-66,700 mature individuals. The overall population trend is considered to be decreasing over three generations (25.89 years) (Wetlands International 2023).
Trend justification
.
Occurs in tropical South America from Colombia south to north Argentina, including north west Peru, and east through Venezuela and the Guianas and throughout Brazil. Widespread, but considered scarce throughout range with the most significant populations in north Venezuela and noted to be reasonably numerous in north east Brazil (del Hoyo et al. 1992, Kear et al. 2005).
Behaviour Mainly sedentary with seasonal or nomadic movements related to water availability; congregates in large numbers at few sites during the dry season Habitat This species inhabits grassy ponds or lakes in llanos, along large rivers and lakes (Johnsgard 1978), swamps (del Hoyo et al. 1992), marshes, floodplains, river deltas (Kear 2005a), flooded forest, pastures and rice-paddies (Kear 2005a) and occasionally sandbars and mudflats (Johnsgard 1978). Diet Its diet is assumed to be similar to that of S. melanotos, though there is little specific data (Kirwan 2013).
Deforestation is likely to affect the species, as is the indiscriminate use of poison to control pests in rice fields (Kirwan 2013). Overhunting may be a problem in parts of the range such as in north east Brazil (Kirwan 2013).
64-75 cm. A large, heavy and distinctive black and white waterbird with a black speckled head and neck. Males possess a large fleshy comb protruding from their upper mandible. Similar species. Knob-billed Duck S. melanotos has pale grey flanks and is slightly larger.
Text account compilers
Rutherford, C.A.
Recommended citation
BirdLife International (2024) Species factsheet: Comb Duck Sarkidiornis sylvicola. Downloaded from
https://datazone.birdlife.org/species/factsheet/comb-duck-sarkidiornis-sylvicola on 22/12/2024.
Recommended citation for factsheets for more than one species: BirdLife International (2024) IUCN Red List for birds. Downloaded from
https://datazone.birdlife.org/species/search on 22/12/2024.