Taxonomic note
Passerculus henslowii (del Hoyo and Collar 2016) was previously placed in the genus Ammodramus following AOU (1998 & supplements); Sibley & Monroe (1990, 1993).
Taxonomic source(s)
del Hoyo, J., Collar, N.J., Christie, D.A., Elliott, A., Fishpool, L.D.C., Boesman, P. and Kirwan, G.M. 2016. HBW and BirdLife International Illustrated Checklist of the Birds of the World. Volume 2: Passerines. Lynx Edicions and BirdLife International, Barcelona, Spain and Cambridge, UK.
Critically Endangered | Endangered | Vulnerable |
---|---|---|
- | - | - |
Year | Category | Criteria |
---|---|---|
2018 | Least Concern | |
2016 | Near Threatened | A2bc+3bc+4bc |
2012 | Near Threatened | A2bc+3bc+4bc |
2008 | Near Threatened | A2b,c; A3b,c; A4b,c |
2004 | Near Threatened | |
2000 | Lower Risk/Least Concern | |
1994 | Lower Risk/Near Threatened | |
1988 | Near Threatened |
Migratory status | full migrant | Forest dependency | Does not normally occur in forest |
Land mass type |
Land-mass type - continent |
Average mass | 12.800000190734863 g |
Estimate | Data quality | |
---|---|---|
Extent of Occurrence breeding/resident (km2) | 2,030,000 | medium |
Extent of Occurrence non-breeding (km2) | 1,490,000 | medium |
Number of locations | - | |
Fragmentation | - |
Estimate | Data quality | Derivation | Year of estimate | |
---|---|---|---|---|
No. of mature individuals | 390000 | medium | estimated | 2016 |
Population trend | Increasing | poor | estimated | - |
Decline (3 years/1 generation past) | - | - | - | |
Decline (5 years/1 generation past) | - | - | - | |
Decline (10 years/1 generation past) | - | - | - | |
Decline (10 years/3 generation future) | - | - | - | |
Decline (10 years/3 generation past and future) | - | - | - | |
Number of subpopulations | - | - | - | |
Largest subpopulations | - | - | - | |
Generation length (yrs) | 3.9 | - | - | - |
Population justification: Rosenberg et al. (2016) estimate the population size to be 390,000 mature individuals.
Trend justification: This species has undergone a non-significant annual increase of 2.68% (6.85% increase to 2.35% decrease) between 2005 and 2015 based on data from the Breeding Bird Survey (Sauer et al. 2017). Longer term trends from Christmas Bird Count data show an annual increase of 9.55% between 1966 and 2017 (T. Meehan in litt. 2018).
Country/Territory | Occurrence status | Presence | Resident | Breeding | Non-breeding | Passage |
---|---|---|---|---|---|---|
Canada | N | Extant | Yes | |||
USA | N | Extant | Yes |
Habitat (level 1) | Habitat (level 2) | Importance | Occurrence |
---|---|---|---|
Artificial/Terrestrial | Pastureland | suitable | non-breeding |
Artificial/Terrestrial | Pastureland | suitable | breeding |
Grassland | Temperate | major | non-breeding |
Grassland | Temperate | major | breeding |
Wetlands (inland) | Bogs, Marshes, Swamps, Fens, Peatlands | suitable | non-breeding |
Wetlands (inland) | Bogs, Marshes, Swamps, Fens, Peatlands | suitable | breeding |
Altitude | Occasional altitudinal limits |
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%) | Unknown | Unknown | ||||||
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Agriculture & aquaculture | Livestock farming & ranching - Scale Unknown/Unrecorded | Timing | Scope | Severity | Impact | ||||
Ongoing | Unknown | Unknown | Unknown | ||||||
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Agriculture & aquaculture | Wood & pulp plantations - Agro-industry plantations | Timing | Scope | Severity | Impact | ||||
Ongoing | Minority (<50%) | Negligible declines | Low Impact: 4 | ||||||
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Natural system modifications | Fire & fire suppression - Supression in fire frequency/intensity | Timing | Scope | Severity | Impact | ||||
Ongoing | Minority (<50%) | Unknown | Unknown | ||||||
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Natural system modifications | Fire & fire suppression - Trend Unknown/Unrecorded | Timing | Scope | Severity | Impact | ||||
Ongoing | Majority (50-90%) | Slow, Significant Declines | Medium Impact: 6 | ||||||
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Pollution | Agricultural & forestry effluents - Type Unknown/Unrecorded | Timing | Scope | Severity | Impact | ||||
Ongoing | Unknown | Unknown | Unknown | ||||||
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Residential & commercial development | Housing & urban areas | Timing | Scope | Severity | Impact | ||||
Ongoing | Minority (<50%) | Unknown | Unknown | ||||||
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Transportation & service corridors | Utility & service lines | Timing | Scope | Severity | Impact | ||||
Ongoing | Minority (<50%) | Unknown | Unknown | ||||||
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Recommended citation
BirdLife International (2019) Species factsheet: Passerculus henslowii. Downloaded from
http://www.birdlife.org on 17/02/2019.
Recommended citation for factsheets for more than one species: BirdLife International (2019) IUCN Red List for birds. Downloaded from
http://www.birdlife.org on 17/02/2019.