Pine Flycatcher (Empidonax affinis) [XC337478]
by Richard E. Webster from Cerro Cinco Millas, near Madera, Chihuahua, Mexico (call)
Pine Flycatcher (Empidonax affinis) [XC322451]
by Jim Holmes from Aliso Spring, Pima County, Arizona, United States (call)
Subspecies
Vocal differences between populations northern and south of Isthmus of Tehuantepec suggest to some that more than one species may be involved.
The following 5 subspecies are recognised:
pulverius Brewster, 1889 - North-western Mexico, from Sonora and Chihuahua south to Jalisco.
trepidus Nelson, 1901 - North-eastern Mexico (Coahuila, Tamaulipas). Winters south to southern Mexico (Chiapas) and Guatemala.
affinis (Swainson, 1827) - Southern Mexican Plateau (Michoacán south to Puebla).
vigensis Phillips, AR, 1942 - Veracruz, in south-eastern Mexico.
bairdi Sclater, PL, 1858 - Southern Mexico (Guerrero and Oaxaca, possibly Chiapas), possibly also western Guatemala.
BirdLife International Species Factsheet