| |
Estimate |
Data quality |
Derivation |
Year of estimate |
| No. of mature individuals |
250000 |
medium |
Estimated |
2009 |
| Population trend |
Decreasing |
|
|
- |
| Number of subpopulations |
|
- |
- |
- |
| Largest subpopulation |
|
- |
- |
- |
| Generation length (yrs) |
7.5 |
- |
- |
- |
|
Population justification: Surveys in 2007-2009 put the wintering population in the Baltic Sea at c.373,000 individuals (Skov et al. 2011), with perhaps a few thousand wintering along coasts elsewhere in Europe, and another c.1,500 wintering in the Black Sea and Caucasus (Delany and Scott 2006). On this basis, the total number of mature individuals (probably around 2/3 of the total population) is estimated at c.250,000. |
|
Trend justification: Since surveys in 1992-1993, an apparent decline of c.60% (3.7% annually) has been detected in the Baltic Sea, with counts in 2007-2009 putting the wintering population at c.373,000 individuals, down from c.933,000 in 1992-1993 (Skov et al. 2011). Extrapolation of the data implies that this is equivalent to a decline of c.77% over the past three generations, estimated at 23 years (based on a generation length of c.7.5 years [BirdLife International unpubl. data]). The Baltic Sea is the most important wintering area in the world for this species, holding c.93% of the global population in 1992-1993. It seems unlikely that the proportion of the total north-west European wintering population present in the Baltic has dropped from 93% to 37% (see Skov et al. 2011), thus a very rapid decline has probably taken place. This is supported by reports of declines elsewhere in its range. A very rapid decline is projected over the next three generations, as the main causes of this negative trend have not been identified with certainty and are not known to have ceased. |
| Threat (level 1) |
Threat (level 2) |
Impact and Stresses |
| Energy production & mining |
Oil & gas drilling |
Timing |
Scope |
Severity |
Impact |
| Ongoing |
Minority (<50%) |
Slow, Significant Decline |
Low Impact: 5 |
| Stresses |
|---|
| Species disturbance, Ecosystem degradation, Ecosystem conversion |
|
| Energy production & mining |
Renewable energy |
Timing |
Scope |
Severity |
Impact |
| Ongoing |
Minority (<50%) |
Negligible declines |
Low Impact: 4 |
| Stresses |
|---|
| Species disturbance |
|
| Biological resource use |
Fishing & harvesting aquatic resources / Unintentional effects: (large scale) |
Timing |
Scope |
Severity |
Impact |
| Ongoing |
Majority (50-90%) |
Slow, Significant Decline |
Medium Impact: |
| Stresses |
|---|
| Species mortality |
|
| Biological resource use |
Hunting & trapping terrestrial animals / Intentional use (species is the target) |
Timing |
Scope |
Severity |
Impact |
| Ongoing |
Minority (<50%) |
Negligible declines |
Low Impact: 4 |
| Stresses |
|---|
| Species mortality |
|
| Human intrusions & disturbance |
Recreational activities |
Timing |
Scope |
Severity |
Impact |
| Ongoing |
Minority (<50%) |
Negligible declines |
Low Impact: 4 |
| Stresses |
|---|
| Species disturbance, Reduced reproductive success |
|
| 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 |
Dams & water management/use / Large dams |
Timing |
Scope |
Severity |
Impact |
| Ongoing |
Minority (<50%) |
Slow, Significant Decline |
Low Impact: 5 |
| Stresses |
|---|
| Ecosystem degradation, Ecosystem conversion |
|
| Invasive non-native/alien species/diseases |
Viral/prion-induced diseases / Unspecified species |
Timing |
Scope |
Severity |
Impact |
| Future |
Majority (50-90%) |
Rapid Declines |
Low Impact: 5 |
| Stresses |
|---|
| Reduced reproductive success, Species mortality |
|
| Invasive non-native/alien species/diseases |
Invasive non-native/alien species/diseases / Unspecified species |
Timing |
Scope |
Severity |
Impact |
| Ongoing |
Minority (<50%) |
Slow, Significant Decline |
Low Impact: 5 |
| Stresses |
|---|
| Reduced reproductive success, Species mortality |
|
| Pollution |
Industrial & military effluents / Oil spills |
Timing |
Scope |
Severity |
Impact |
| Ongoing |
Majority (50-90%) |
Slow, Significant Decline |
Medium Impact: |
| Stresses |
|---|
| Reduced reproductive success, Species mortality |
|
| Pollution |
Industrial & military effluents / Type Unknown/Unrecorded |
Timing |
Scope |
Severity |
Impact |
| Ongoing |
Majority (50-90%) |
Negligible declines |
Low Impact: 5 |
| Stresses |
|---|
| Indirect ecosystem effects, Reduced reproductive success, Species mortality |
|
| Climate change & severe weather |
Habitat shifting & alteration |
Timing |
Scope |
Severity |
Impact |
| Future |
Whole (>90%) |
Unknown |
Unknown |
| Stresses |
|---|
| Indirect ecosystem effects, 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.
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