Data Zone
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: https://www.museum.lsu.edu/~Remsen/SACCBaseline.htm.
| Critically Endangered | Endangered | Vulnerable |
|---|---|---|
| - | - | - |
| 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 |
| Migratory status | full migrant | Forest dependency | low |
| Land-mass type | Average mass | - |
| Estimate | Data quality | |
|---|---|---|
| Extent of Occurrence (breeding/resident) | 9,860,000 km2 | medium |
| Extent of Occurrence (non-breeding) | 4,120,000 km2 | medium |
| Severely fragmented? | no | - |
| Estimate | Data quality | Derivation | Year of estimate | |
|---|---|---|---|---|
| Population size | 8100000 mature individuals | poor | estimated | 2020 |
| Population trend | decreasing | - | estimated | - |
| Generation length | 2.73 years | - | - | - |
Population justification: The global population is estimated to number 8,100,000 mature individuals (Partners in Flight 2020).
Trend justification:
The species has been undergoing a moderate decline between 1970 and 2017, at an average rate of 12% over ten years (Partners in Flight 2019; Rosenberg et al. 2019).
| Country/Territory | Presence | Origin | Resident | Breeding visitor | Non-breeding visitor | Passage migrant |
|---|---|---|---|---|---|---|
| Belize | extant | native | yes | |||
| Canada | extant | native | yes | |||
| Colombia | extant | native | yes | |||
| Costa Rica | extant | native | yes | yes | ||
| Cuba | extant | vagrant | yes | |||
| Ecuador | extant | native | yes | |||
| El Salvador | extant | native | yes | yes | ||
| Guatemala | extant | native | yes | yes | ||
| Honduras | extant | native | yes | yes | ||
| Mexico | extant | native | yes | yes | ||
| Nicaragua | extant | native | yes | yes | ||
| Panama | extant | native | yes | yes | ||
| Puerto Rico (to USA) | extant | vagrant | ||||
| USA | extant | native | yes | yes | ||
| Venezuela | extant | native | yes |
| Country/Territory | IBA Name |
|---|
| Habitat (level 1) | Habitat (level 2) | Importance | Occurrence |
|---|---|---|---|
| Artificial/Terrestrial | Pastureland | suitable | non-breeding |
| Forest | Subtropical/Tropical Moist Lowland | suitable | non-breeding |
| Shrubland | Subtropical/Tropical Dry | suitable | non-breeding |
| Shrubland | Subtropical/Tropical Moist | major | breeding |
| Shrubland | Temperate | major | breeding |
| Wetlands (inland) | Shrub Dominated Wetlands | suitable | breeding |
| Altitude | 0 - 2500 m | Occasional altitudinal limits |
Recommended citation
BirdLife International (2024) Species factsheet: Willow Flycatcher Empidonax traillii. Downloaded from
https://datazone.birdlife.org/species/factsheet/willow-flycatcher-empidonax-traillii on 22/11/2024.
Recommended citation for factsheets for more than one species: BirdLife International (2024) IUCN Red List for birds. Downloaded from
https://datazone.birdlife.org/species/search on 22/11/2024.