Bachman's Sparrow Peucaea aestivalis


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.

IUCN Red List criteria met and history
Red List criteria met
Critically Endangered Endangered Vulnerable
- - -

Red List history
Year Category Criteria
2020 Near Threatened A2abc+3bc+4abc
2018 Near Threatened A2ac+3c+4ac
2016 Near Threatened A2c
2012 Near Threatened A2c
2008 Near Threatened A2c
2004 Near Threatened
2000 Lower Risk/Near Threatened
1994 Lower Risk/Least Concern
1988 Lower Risk/Least Concern
Species attributes

Migratory status not a migrant Forest dependency medium
Land-mass type Land-mass type - continent
Average mass 19 g

Estimate Data quality
Extent of Occurrence breeding/resident (km2) 1,650,000 medium
Extent of Occurrence non-breeding (km2) 1,150,000 medium
Severely fragmented? no -
Population and trend
Value Data quality Derivation Year of estimate
Number of mature individuals 170000 medium estimated 2019
Population trend decreasing medium estimated 2014-2024
Decline % (10 years/3 generations future) 20-29 - - -
Decline % (10 years/3 generations past and future) 20-29 - - -
Generation length (years) 2.19 - - -

Population justification: Partners in Flight (2019) estimate the population size at 170,000 mature individuals.

Trend justification: Data from the Breeding Bird Survey suggests that between 2010-2015, the species underwent an ~2.52% annual decline, which equates to a ~22.5% decline across the stipulated ten year period (Sauer et al. 2017). Similarly, the Christmas Bird Count (between 1966 and 2017) suggests annual declines of a comparable magnitude, ~2.61% per year, which equates to a ~23.2% decline across the ten year period (Meehan et al. 2018). Finally, Partners in Flight (2019) have given the species a half-life of ~24 years, which equates to an annual decline of ~3.1%, or ~26.8% decline over the next ten years. Given all such calculations. the rate of decline is placed in the range 20-29%.

Country/territory distribution
Country/Territory Presence Origin Resident Breeding Non-breeding Passage
USA extant native yes

Important Bird and Biodiversity Areas (IBA)
Country/Territory IBA Name
USA Kissimmee Prairie Preserve and State Park
USA Shortleaf Pine-Bluestem Grass Ecosystem Management Area
USA Ichetucknee Springs State Park
USA Myakka River Watershed
USA Wekiwa Basin GEOPark
USA Babcock-Webb Ecosystem
USA Sandhills West
USA Fort Chaffee

Habitats & altitude
Habitat (level 1) Habitat (level 2) Importance Occurrence
Forest Subtropical/Tropical Dry major resident
Forest Temperate major resident
Shrubland Temperate suitable resident
Altitude 0 - 900 m Occasional altitudinal limits  

Threats & impact
Threat (level 1) Threat (level 2) Impact and Stresses
Biological resource use Logging & wood harvesting - Unintentional effects: (subsistence/small scale) [harvest] Timing Scope Severity Impact
Ongoing Majority (50-90%) Slow, Significant Declines Medium Impact: 6
Ecosystem degradation
Human intrusions & disturbance Recreational activities Timing Scope Severity Impact
Ongoing Minority (<50%) No decline Low Impact: 4
Species disturbance
Natural system modifications Fire & fire suppression - Supression in fire frequency/intensity Timing Scope Severity Impact
Ongoing Majority (50-90%) Negligible declines Low Impact: 5
Ecosystem degradation
Residential & commercial development Housing & urban areas Timing Scope Severity Impact
Ongoing Minority (<50%) Slow, Significant Declines Low Impact: 5
Indirect ecosystem effects, Ecosystem degradation, Ecosystem conversion
Transportation & service corridors Utility & service lines Timing Scope Severity Impact
Ongoing Minority (<50%) Negligible declines Low Impact: 4
Species mortality

Purpose Primary form used Life stage used Source Scale Level Timing
Pets/display animals, horticulture - - international non-trivial recent

Recommended citation
BirdLife International (2023) Species factsheet: Peucaea aestivalis. Downloaded from http://datazone.birdlife.org/species/factsheet/bachmans-sparrow-peucaea-aestivalis on 03/10/2023. Recommended citation for factsheets for more than one species: BirdLife International (2023) IUCN Red List for birds. Downloaded from http://datazone.birdlife.org on 03/10/2023.