Kentucky Warbler Geothlypis formosa


Taxonomic note

Geothlypis formosa (del Hoyo and Collar 2016) was previously placed in the genus Oporornis and listed as O. formosus following AOU (1998 & supplements); SACC (2005 & updates); Sibley & Monroe (1990, 1993); Stotz et al. (1996).


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.
SACC. 2005 and updates. A classification of the bird species of South America. Available at: #

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

Red List history
Year Category Criteria
2021 Least Concern
2016 Least Concern
2012 Least Concern
2009 Least Concern
2008 Least Concern
2004 Least Concern
2000 Lower Risk/Least Concern
1994 Lower Risk/Least Concern
1988 Lower Risk/Least Concern
Species attributes

Migratory status full migrant Forest dependency medium
Land-mass type Average mass 14 g

Estimate Data quality
Extent of Occurrence breeding/resident (km2) 2,590,000 medium
Extent of Occurrence non-breeding (km2) 5,500,000 medium
Severely fragmented? no -
Population and trend
Value Data quality Derivation Year of estimate
Number of mature individuals 2600000 poor estimated 2019
Population trend decreasing estimated -
Generation length (years) 2.45 - - -

Population justification: The global population is estimated to number 2.6 million mature individuals (Partners in Flight 2019).

Trend justification: The species is undergoing a moderate decline (Partners in Flight 2019; Rosenberg et al. 2019). Short-term trends suggest that the population has been declining by 12% over the past ten years (Pardieck et al. 2018).

Country/territory distribution
Country/Territory Presence Origin Resident Breeding Non-breeding Passage
Antigua and Barbuda extant vagrant yes
Aruba (to Netherlands) extant vagrant yes
Bahamas extant native yes
Barbados extant vagrant yes
Belize extant native yes
Bonaire, Sint Eustatius and Saba (to Netherlands) extant vagrant yes
Canada extant vagrant
Cayman Islands (to UK) extant native yes
Colombia extant native yes
Costa Rica extant native yes
Cuba extant native yes
Curaçao (to Netherlands) extant vagrant yes
Dominica extant vagrant yes
Dominican Republic extant native yes
El Salvador extant native yes
Guadeloupe (to France) extant vagrant yes
Guatemala extant native yes yes
Haiti extant native yes
Honduras extant native yes yes
Jamaica extant native yes
Martinique (to France) extant vagrant yes
Mexico extant native yes yes
Montserrat (to UK) extant vagrant yes
Nicaragua extant native yes yes
Panama extant native yes
Puerto Rico (to USA) extant native yes
St Kitts and Nevis extant vagrant yes
St Lucia extant vagrant yes
St Vincent and the Grenadines extant vagrant yes
Turks and Caicos Islands (to UK) extant native yes
USA extant native yes yes
Venezuela extant native yes
Virgin Islands (to UK) extant native yes
Virgin Islands (to USA) extant native yes

Important Bird and Biodiversity Areas (IBA)
Country/Territory IBA Name

Habitats & altitude
Habitat (level 1) Habitat (level 2) Importance Occurrence
Forest Subtropical/Tropical Moist Lowland major non-breeding
Forest Temperate major breeding
Altitude   Occasional altitudinal limits (max) 1850 m

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: Geothlypis formosa. Downloaded from on 26/09/2023. Recommended citation for factsheets for more than one species: BirdLife International (2023) IUCN Red List for birds. Downloaded from on 26/09/2023.