IUCN Red List Criteria
| Critically Endangered |
C2a(i) |
| Endangered |
C2a(i);D |
| Vulnerable |
A2ce+3ce+4ce;C1+2a(i);D1 |
IUCN Red List history
| Year |
Category |
| 2012 |
Critically Endangered |
| 2010 |
Critically Endangered |
| 2009 |
Critically Endangered |
| 2008 |
Critically Endangered |
| 2006 |
Critically Endangered |
| 2004 |
Critically Endangered |
| 2000 |
Critically Endangered |
| 1996 |
Critically Endangered |
| 1994 |
Critically Endangered |
| 1988 |
Threatened |
Species attributes
| Migratory status |
not a migrant |
Forest dependency |
Does not normally occur in forest |
| Land mass type |
continent
|
Average mass |
- |
Distribution
| |
Estimate |
Data quality |
| Extent of Occurrence breeding/resident (km2) |
32,600 |
medium |
| Number of locations |
8 |
- |
| Fragmentation |
|
- |
Population & trend
| |
Estimate |
Data quality |
Derivation |
Year of estimate |
| No. of mature individuals |
50-249 |
medium |
Estimated |
1994 |
| Population trend |
Decreasing |
poor |
|
- |
| Number of subpopulations |
6 |
- |
- |
- |
| Largest subpopulation |
1-50 |
- |
- |
- |
| Generation length (yrs) |
6.5 |
- |
- |
- |
|
Population justification: The population was estimated at 250 individuals in 1992. Although no complete census has been conducted since this estimate, threats have continued, hence the current population is likely to be lower than this figure, thus the population is placed in the band 50-249 mature individuals. There are recent suggestions that the population may exceed this figure (L. V. Lins in litt. 2012), but this requires confirmation. |
|
Trend justification: This species's population is suspected to have declined rapidly over the last ten years, in line with habitat loss and degradation within its range, owing to the expansion of hydroelectric power schemes, soy bean cultivation and mining operations. It appears to have been extirpated from Paraguay. |
Country/Territory distribution
| Country/Territory |
Occurrence status |
Extinct |
Breeding |
Non-breeding |
Passage |
| Argentina |
Native |
No |
Yes |
|
|
| Brazil |
Native |
No |
Yes |
|
|
| Paraguay |
Native |
No |
Yes |
|
|
Important Bird Areas where this species has triggered the IBA criteria
| Country/Territory |
IBA Name |
IBA link |
| Argentina |
Cuenca del Piray Miní |
 |
| Argentina |
Parque Provincial Urugua-í |
|
| Brazil |
Jalapão |
|
| Brazil |
Parque Nacional da Chapada dos Veadeiros e Adjacências |
|
| Brazil |
Rio Arrojado |
|
| Brazil |
Serra da Canastra |
|
Habitats & altitude
| Habitat (level 1) |
Habitat (level 2) |
Importance |
Occurrence |
| Wetlands (inland) |
Permanent Rivers/Streams/Creeks (includes waterfalls) |
major |
resident |
|
Altitude
|
0 - 1100 m
|
Occasional altitudinal limits
|
|
Threats & impact
| Threat (level 1) |
Threat (level 2) |
Impact and Stresses |
| Agriculture & Aquaculture |
Annual & perennial non-timber crops / Agro-industry farming |
Timing |
Scope |
Severity |
Impact |
| Ongoing |
Majority (50-90%) |
Rapid Declines |
Medium Impact: |
| Stresses |
|---|
| Ecosystem degradation, Ecosystem conversion |
|
| Energy production & mining |
Mining & quarrying |
Timing |
Scope |
Severity |
Impact |
| Ongoing |
Majority (50-90%) |
Slow, Significant Decline |
Medium Impact: |
| Stresses |
|---|
| Ecosystem degradation, Ecosystem conversion |
|
| Biological resource use |
Fishing & harvesting aquatic resources / Unintentional effects: (subsistence/small scale) |
Timing |
Scope |
Severity |
Impact |
| Ongoing |
Majority (50-90%) |
Slow, Significant Decline |
Medium Impact: |
| Stresses |
|---|
| Ecosystem degradation, Ecosystem conversion |
|
| Biological resource use |
Hunting & trapping terrestrial animals / Intentional use (species is the target) |
Timing |
Scope |
Severity |
Impact |
| Ongoing |
Minority (<50%) |
Slow, Significant Decline |
Low Impact: 5 |
| Stresses |
|---|
| Species mortality |
|
| Human intrusions & disturbance |
Recreational activities |
Timing |
Scope |
Severity |
Impact |
| Ongoing |
Minority (<50%) |
Rapid Declines |
Medium Impact: |
| Stresses |
|---|
| Species disturbance |
|
| Natural system modifications |
Dams & water management/use / Dams (size unknown) |
Timing |
Scope |
Severity |
Impact |
| Ongoing |
Majority (50-90%) |
Rapid Declines |
Medium Impact: |
| Stresses |
|---|
| Ecosystem degradation, Ecosystem conversion |
|
| Pollution |
Agricultural & forestry effluents / Type Unknown/Unrecorded |
Timing |
Scope |
Severity |
Impact |
| Ongoing |
Minority (<50%) |
Slow, Significant Decline |
Low Impact: 5 |
| Stresses |
|---|
| Ecosystem degradation, Ecosystem conversion |
|
Utilisation
| Purpose |
Primary form used |
Life stage used |
Source |
Scale |
Level |
Timing |
| Sport |
Whole |
Adults and juveniles |
Wild |
Subsistence, National |
Non-trivial |
Recent |
Recommended citation
BirdLife International (2013) Species factsheet: Mergus octosetaceus. Downloaded from
http://www.birdlife.org on 19/06/2013.
Recommended citation for factsheets for more than one species: BirdLife International (2013) IUCN Red List for birds. Downloaded from
http://www.birdlife.org on 19/06/2013.
This information is based upon, and updates, the information published in BirdLife International (2000)
Threatened birds of the world. Barcelona and Cambridge, UK: Lynx Edicions and BirdLife International, BirdLife International (2004)
Threatened birds of the world 2004 CD-ROM and BirdLife International (2008) Threatened birds of the world 2008 CD-ROM. These sources provide the information for species accounts for the birds on the IUCN Red List.
To provide new information to update this factsheet or to correct any errors, please email BirdLife
To contribute to discussions on the evaluation of the IUCN Red List status of Globally Threatened Birds, please visit BirdLife's Globally Threatened Bird Forums.
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