LC
Pacific-slope Flycatcher Empidonax difficilis



Taxonomy

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
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 10.69999981 g
Extent of occurrence (EOO)

Estimate Data quality
Extent of Occurrence breeding/resident (km2) 3,520,000 medium
Extent of Occurrence non-breeding (km2) 1,150,000 medium
Number of locations -
Fragmentation -
Population and trend
Estimate Data quality Derivation Year of estimate
No. of mature individuals poor estimated 2009
Population trend Decreasing 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) 3.7 - - -

Trend justification: This species has undergone a small or statistically insignificant decrease over the last 40 years in North America (data for Empidonax difficilis and E. occidentalis combined, from Breeding Bird Survey and/or Christmas Bird Count: Butcher and Niven 2007).


Country/territory distribution
Country/Territory Occurrence status Presence Resident Breeding Non-breeding Passage
Canada N Extant Yes
Mexico N Extant
USA N Extant Yes

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

Habitats & altitude
Habitat (level 1) Habitat (level 2) Importance Occurrence
Forest Subtropical/Tropical Dry major breeding
Forest Subtropical/Tropical Moist Lowland major breeding
Forest Subtropical/Tropical Moist Lowland major non-breeding
Forest Subtropical/Tropical Moist Montane major non-breeding
Wetlands (inland) Permanent Rivers/Streams/Creeks (includes waterfalls) suitable breeding
Altitude 1500 - 3500 m Occasional altitudinal limits  

Recommended citation
BirdLife International (2019) Species factsheet: Empidonax difficilis. 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.