IUCN Red List Criteria
| Critically Endangered |
|
| Endangered |
A2e+3e+4e |
| Vulnerable |
A2e+3e+4e;B1ab(v) |
IUCN Red List history
| Year |
Category |
| 2012 |
Endangered |
| 2008 |
Endangered |
| 2004 |
Endangered |
| 2000 |
Endangered |
| 1994 |
Not Recognised |
| 1988 |
Not Recognised |
Species attributes
| Migratory status |
not a migrant |
Forest dependency |
Medium |
| Land mass type |
|
Average mass |
- |
Distribution
| |
Estimate |
Data quality |
| Extent of Occurrence breeding/resident (km2) |
730 |
medium |
| Number of locations |
6-10 |
- |
| Fragmentation |
|
- |
Population & trend
| |
Estimate |
Data quality |
Derivation |
Year of estimate |
| No. of mature individuals |
2100-2300 |
good |
Estimated |
1999 |
| Population trend |
Decreasing |
poor |
|
- |
| Number of subpopulations |
3 |
- |
- |
- |
| Largest subpopulation |
1001-3100 |
- |
- |
- |
| Generation length (yrs) |
5 |
- |
- |
- |
|
Population justification: The population estimate of 3,200-3,500 individuals is derived from G. Wiles in litt. and Wiles & Woodside (1999). This is roughly equivalent to 2,100-2,300 mature individuals. |
|
Trend justification: Population estimates have fluctuated over the last two decades but appear to be increasing. Recent population estimates on Saipan indicate that the population has increased to approximately 5,400 individuals from 1985 to 2005 (J. Cruz et al. in litt. 2007). The population on Guam is also believed to have increased to approximately 900 individuals from 1983 to 2006 (A. Brooke in litt. 2006) while the population on Aguijan appears stable at around 400 individuals based on 2002 surveys (J. Cruz et al. in litt. 2007). However, on Saipan, the species's stronghold, brown tree snake Boiga irregularis is in the process of becoming established (Rodd and Savidge 2007), which is expected to cause a very rapid decline. |
Country/Territory distribution
| Country/Territory |
Occurrence status |
Extinct |
Breeding |
Non-breeding |
Passage |
| Guam (to USA) |
Native |
No |
Yes |
|
|
| Northern Mariana Islands (to USA) |
Native |
No |
Yes |
|
|
| USA |
Introduced |
No |
Yes |
|
|
Habitats & altitude
| Habitat (level 1) |
Habitat (level 2) |
Importance |
Occurrence |
| Artificial/Terrestrial |
Pastureland |
suitable |
resident |
| Caves and Subterranean Habitats (non-aquatic) |
Caves |
major |
breeding |
| Forest |
Subtropical/Tropical Mangrove Vegetation Above High Tide Level |
suitable |
resident |
| Forest |
Subtropical/Tropical Moist Lowland |
major |
resident |
|
Altitude
|
0 - 600 m
|
Occasional altitudinal limits
|
|
Threats & impact
| Threat (level 1) |
Threat (level 2) |
Impact and Stresses |
| Human intrusions & disturbance |
Recreational activities |
Timing |
Scope |
Severity |
Impact |
| Ongoing |
Minority (<50%) |
Negligible declines |
Low Impact: 4 |
| Stresses |
|---|
| Species disturbance |
|
| Invasive non-native/alien species/diseases |
Problematic native species/diseases / Brown Tree Snake (Boiga irregularis) |
Timing |
Scope |
Severity |
Impact |
| Ongoing |
Majority (50-90%) |
Rapid Declines |
Medium Impact: |
| Stresses |
|---|
| Species mortality |
|
| Invasive non-native/alien species/diseases |
Invasive non-native/alien species/diseases / Goat (Capra hircus) |
Timing |
Scope |
Severity |
Impact |
| Ongoing |
Minority (<50%) |
Slow, Significant Decline |
Low Impact: 5 |
| Stresses |
|---|
| Species disturbance |
|
| Invasive non-native/alien species/diseases |
Invasive non-native/alien species/diseases / Unspecified cockroach (Blatodea) |
Timing |
Scope |
Severity |
Impact |
| Ongoing |
Minority (<50%) |
Slow, Significant Decline |
Low Impact: 5 |
| Stresses |
|---|
| Reduced reproductive success |
|
| Invasive non-native/alien species/diseases |
Invasive non-native/alien species/diseases / Unspecified wasps (Vespula spp.) |
Timing |
Scope |
Severity |
Impact |
| Ongoing |
Minority (<50%) |
Slow, Significant Decline |
Low Impact: 5 |
| Stresses |
|---|
| Reduced reproductive success |
|
| Pollution |
Agricultural & forestry effluents / Herbicides and pesticides |
Timing |
Scope |
Severity |
Impact |
| Ongoing |
Minority (<50%) |
Unknown |
Unknown |
| Stresses |
|---|
| Reduced reproductive success |
|
Recommended citation
BirdLife International (2013) Species factsheet: Collocalia bartschi. 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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