| |
Estimate |
Data quality |
Derivation |
Year of estimate |
| No. of mature individuals |
|
poor |
Estimated |
2009 |
| Population trend |
Decreasing |
|
|
- |
| Number of subpopulations |
|
- |
- |
- |
| Largest subpopulation |
|
- |
- |
- |
| Generation length (yrs) |
5.6 |
- |
- |
- |
|
Population justification: The global population is estimated to number c.180,000-1,300,000 individuals (Wetlands International 2006), while national population estimates include: c.10,000-100,000 breeding pairs, c.1,000-10,000 individuals on migration and c.1,000-10,000 wintering individuals in China; < c.100 breeding pairs and c.1,000-10,000 wintering individuals in Taiwan; c.100-10,000 breeding pairs, c.50-1,000 individuals on migration and < c.50 wintering individuals in Korea and c.10,000-100,000 breeding pairs, c.1,000-10,000 individuals on migration and < c.50 wintering individuals in Japan (Brazil 2009). |
|
Trend justification: The overall population trend is decreasing, although some populations may be stable and others have unknown trends (Wetlands International 2006). |
| Habitat (level 1) |
Habitat (level 2) |
Importance |
Occurrence |
| Artificial/Aquatic & Marine |
Irrigated Land (includes irrigation channels) |
suitable |
breeding |
| Artificial/Aquatic & Marine |
Irrigated Land (includes irrigation channels) |
suitable |
non-breeding |
| Artificial/Aquatic & Marine |
Ponds (below 8ha) |
suitable |
non-breeding |
| Artificial/Aquatic & Marine |
Ponds (below 8ha) |
suitable |
breeding |
| Artificial/Aquatic & Marine |
Seasonally Flooded Agricultural Land |
suitable |
non-breeding |
| Artificial/Aquatic & Marine |
Seasonally Flooded Agricultural Land |
suitable |
breeding |
| Forest |
Subtropical/Tropical Mangrove Vegetation Above High Tide Level |
suitable |
breeding |
| Forest |
Subtropical/Tropical Mangrove Vegetation Above High Tide Level |
suitable |
non-breeding |
| Forest |
Subtropical/Tropical Swamp |
suitable |
breeding |
| Forest |
Subtropical/Tropical Swamp |
suitable |
non-breeding |
| Grassland |
Subtropical/Tropical Seasonally Wet/Flooded |
suitable |
breeding |
| Grassland |
Subtropical/Tropical Seasonally Wet/Flooded |
suitable |
non-breeding |
| Marine Coastal/Supratidal |
Coastal Brackish/Saline Lagoons/Marine Lakes |
suitable |
non-breeding |
| Marine Coastal/Supratidal |
Coastal Brackish/Saline Lagoons/Marine Lakes |
suitable |
breeding |
| Marine Coastal/Supratidal |
Coastal Freshwater Lakes |
suitable |
non-breeding |
| Marine Coastal/Supratidal |
Coastal Freshwater Lakes |
suitable |
breeding |
| Marine Intertidal |
Mud Flats and Salt Flats |
suitable |
breeding |
| Marine Intertidal |
Mud Flats and Salt Flats |
suitable |
non-breeding |
| Marine Intertidal |
Salt Marshes (Emergent Grasses) |
suitable |
non-breeding |
| Marine Intertidal |
Salt Marshes (Emergent Grasses) |
suitable |
breeding |
| Marine Neritic |
Estuaries |
suitable |
non-breeding |
| Marine Neritic |
Estuaries |
suitable |
breeding |
| Wetlands (inland) |
Bogs, Marshes, Swamps, Fens, Peatlands |
suitable |
breeding |
| Wetlands (inland) |
Bogs, Marshes, Swamps, Fens, Peatlands |
suitable |
non-breeding |
| Wetlands (inland) |
Permanent Freshwater Lakes (over 8ha) |
suitable |
non-breeding |
| Wetlands (inland) |
Permanent Freshwater Lakes (over 8ha) |
suitable |
breeding |
| Wetlands (inland) |
Permanent Inland Deltas |
suitable |
non-breeding |
| Wetlands (inland) |
Permanent Inland Deltas |
suitable |
breeding |
| Wetlands (inland) |
Permanent Rivers/Streams/Creeks (includes waterfalls) |
suitable |
non-breeding |
| Wetlands (inland) |
Permanent Rivers/Streams/Creeks (includes waterfalls) |
suitable |
breeding |
| Wetlands (inland) |
Permanent Saline, Brackish or Alkaline Marshes/Pools |
suitable |
non-breeding |
| Wetlands (inland) |
Permanent Saline, Brackish or Alkaline Marshes/Pools |
suitable |
breeding |
| Wetlands (inland) |
Seasonal/Intermittent Freshwater Lakes (over 8ha) |
suitable |
breeding |
| Wetlands (inland) |
Seasonal/Intermittent Freshwater Lakes (over 8ha) |
suitable |
non-breeding |
| Wetlands (inland) |
Seasonal/Intermittent Freshwater Marshes/Pools (under 8ha) |
suitable |
non-breeding |
| Wetlands (inland) |
Seasonal/Intermittent Freshwater Marshes/Pools (under 8ha) |
suitable |
breeding |
| Wetlands (inland) |
Seasonal/Intermittent Saline, Brackish or Alkaline Lakes and Flats |
suitable |
non-breeding |
| Wetlands (inland) |
Seasonal/Intermittent Saline, Brackish or Alkaline Lakes and Flats |
suitable |
breeding |
|
Altitude
|
0 - 1450 m
|
Occasional altitudinal limits
|
|
| Threat (level 1) |
Threat (level 2) |
Impact and Stresses |
| Biological resource use |
Fishing & harvesting aquatic resources / Unintentional effects: (subsistence/small scale) |
Timing |
Scope |
Severity |
Impact |
| Ongoing |
Minority (<50%) |
Slow, Significant Decline |
Low Impact: 5 |
| Stresses |
| Ecosystem degradation, Ecosystem conversion |
|
| Natural system modifications |
Dams & water management/use / Abstraction of surface water (agricultural use) |
Timing |
Scope |
Severity |
Impact |
| Ongoing |
Minority (<50%) |
Slow, Significant Decline |
Low Impact: 5 |
| Stresses |
| Ecosystem degradation, Ecosystem conversion |
|
| Natural system modifications |
Fire & fire suppression / Increase in fire frequency/intensity |
Timing |
Scope |
Severity |
Impact |
| Ongoing |
Minority (<50%) |
Slow, Significant Decline |
Low Impact: 5 |
| Stresses |
| Species disturbance, Ecosystem degradation, Ecosystem conversion |
|
| Invasive non-native/alien species/diseases |
Invasive non-native/alien species/diseases / plant (Mimosa pigra) |
Timing |
Scope |
Severity |
Impact |
| Ongoing |
Minority (<50%) |
Slow, Significant Decline |
Low Impact: 5 |
| Stresses |
| Ecosystem degradation, Ecosystem conversion |
|
| Invasive non-native/alien species/diseases |
Invasive non-native/alien species/diseases / plant (Salvinia molesta) |
Timing |
Scope |
Severity |
Impact |
| Ongoing |
Minority (<50%) |
Slow, Significant Decline |
Low Impact: 5 |
| Stresses |
| Ecosystem degradation, Ecosystem conversion |
|
| Invasive non-native/alien species/diseases |
Invasive non-native/alien species/diseases / Water Buffalo (Bubalus bubalis) |
Timing |
Scope |
Severity |
Impact |
| Ongoing |
Minority (<50%) |
Slow, Significant Decline |
Low Impact: 5 |
| Stresses |
| Ecosystem degradation, Ecosystem conversion |
|
| Pollution |
Industrial & military effluents / Seepage from mining |
Timing |
Scope |
Severity |
Impact |
| Ongoing |
Minority (<50%) |
Slow, Significant Decline |
Low Impact: 5 |
| Stresses |
| Ecosystem degradation, Ecosystem conversion |
|
| Pollution |
Domestic & urban waste water / Type Unknown/Unrecorded |
Timing |
Scope |
Severity |
Impact |
| Ongoing |
Minority (<50%) |
Slow, Significant Decline |
Low Impact: 5 |
| Stresses |
| Species mortality |
|
| Climate change & severe weather |
Habitat shifting & alteration |
Timing |
Scope |
Severity |
Impact |
| Future |
Minority (<50%) |
Unknown |
Unknown |
| Stresses |
| Ecosystem degradation, Ecosystem conversion |
|
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.