| |
Estimate |
Data quality |
Derivation |
Year of estimate |
| No. of mature individuals |
1700 |
medium |
Estimated |
2005 |
| Population trend |
Decreasing |
medium |
|
- |
| Number of subpopulations |
7 |
- |
- |
- |
| Largest subpopulation |
2000 |
- |
- |
- |
| Generation length (yrs) |
5.2 |
- |
- |
- |
|
Population justification: The population is estimated to number 1,700 mature individuals, roughly equating to 2,500-2,600 individuals in total (C. Braun in litt. 2005, J. R. Young in litt. 2005). |
|
Trend justification: There have been long-term declines in lek sites, males at leks and offspring (BLM 1999, J. R. Young in litt. 1999, Storch 2000, Young et al. 2000), thus the population is estimated to be experiencing a moderate and ongoing population decline. |
| Threat (level 1) |
Threat (level 2) |
Impact and Stresses |
| Residential & commercial development |
Housing & urban areas |
Timing |
Scope |
Severity |
Impact |
| Ongoing |
Minority (<50%) |
Negligible declines |
Low Impact: 4 |
| Stresses |
| Ecosystem degradation, Ecosystem conversion |
|
| Agriculture & Aquaculture |
Annual & perennial non-timber crops / Agro-industry farming |
Timing |
Scope |
Severity |
Impact |
| Ongoing |
Minority (<50%) |
Negligible declines |
Low Impact: 4 |
| Stresses |
| Ecosystem degradation, Ecosystem conversion |
|
| Agriculture & Aquaculture |
Livestock farming & ranching / Agro-industry grazing, ranching or farming |
Timing |
Scope |
Severity |
Impact |
| Ongoing |
Minority (<50%) |
Negligible declines |
Low Impact: 4 |
| Stresses |
| Ecosystem degradation, Ecosystem conversion |
|
| Energy production & mining |
Oil & gas drilling |
Timing |
Scope |
Severity |
Impact |
| Future |
Minority (<50%) |
Rapid Declines |
Low Impact: 4 |
| Stresses |
| Ecosystem degradation, Ecosystem conversion |
|
| Transportation & service corridors |
Roads & railroads |
Timing |
Scope |
Severity |
Impact |
| Past, Unlikely to Return |
Minority (<50%) |
Rapid Declines |
Past Impact |
| Stresses |
| Ecosystem degradation, Ecosystem conversion |
|
| Transportation & service corridors |
Utility & service lines |
Timing |
Scope |
Severity |
Impact |
| Ongoing |
Minority (<50%) |
Negligible declines |
Low Impact: 4 |
| Stresses |
| Ecosystem degradation, Ecosystem conversion, Species mortality |
|
| Biological resource use |
Hunting & trapping terrestrial animals / Intentional use (species is the target) |
Timing |
Scope |
Severity |
Impact |
| Past, Unlikely to Return |
Minority (<50%) |
Slow, Significant Decline |
Past Impact |
| Stresses |
| Species mortality |
|
| Human intrusions & disturbance |
Recreational activities |
Timing |
Scope |
Severity |
Impact |
| Ongoing |
Minority (<50%) |
Negligible declines |
Low Impact: 4 |
| Stresses |
| Species disturbance |
|
| Human intrusions & disturbance |
Work & other activities |
Timing |
Scope |
Severity |
Impact |
| Ongoing |
Minority (<50%) |
Negligible declines |
Low Impact: 4 |
| Stresses |
| Species disturbance |
|
| Natural system modifications |
Dams & water management/use / Small dams |
Timing |
Scope |
Severity |
Impact |
| Past, Unlikely to Return |
Minority (<50%) |
Negligible declines |
Past Impact |
| Stresses |
| Ecosystem degradation, Ecosystem conversion |
|
| Invasive non-native/alien species/diseases |
Problematic native species/diseases |
Timing |
Scope |
Severity |
Impact |
| Ongoing |
Minority (<50%) |
Negligible declines |
Low Impact: 4 |
| Stresses |
| Ecosystem degradation, Ecosystem conversion |
|
| Invasive non-native/alien species/diseases |
Invasive non-native/alien species/diseases / West Nile Virus (Flaviviridae) |
Timing |
Scope |
Severity |
Impact |
| Future |
Minority (<50%) |
Rapid Declines |
Low Impact: 4 |
| Stresses |
| Species mortality |
|
| Climate change & severe weather |
Temperature extremes |
Timing |
Scope |
Severity |
Impact |
| Ongoing |
Majority (50-90%) |
Causing/Could cause fluct |
Medium Impact: |
| Stresses |
| Species mortality |
|
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
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