Tyrant-flycatchers (Tyrannidae)

Pacific-slope Flycatcher (Empidonax difficilis) - HBW 9, p. 364

French: Moucherolle côtier German: Feuchtwald-Schnäppertyrann Spanish: Mosquero del Pacífico
Other common names: Coastal/Redwoods Flycatcher; Western Flycatcher (when grouped with E. occidentalis)

Taxonomy: Empidonax difficilis S. F. Baird, 1858, Fort Steilacoom, Washington, USA.
Formerly treated as conspecific with E. occidentalis; separated on grounds of differences in voice, morphology and allozymes, but this treatment questioned by some authorities; further study perhaps warranted in area where the two contact each other (interior NW of North America). Sometimes E. flavescens considered conspecific. Channel Is race insulicola possibly a separate species, differs from mainland populations in morphology, voice, habitat use and genetics. Three subspecies recognized.

Subspecies and Distribution:

difficilis S. F. Baird, 1858 - breeds from SE Alaska S to S California (generally W of Sierra Nevadas) and extreme NW Mexico (N Baja California); winters W Mexico (S to S Baja California, Sinaloa and Oaxaca).
insulicola Oberholser, 1897 - breeds on Channel Is, off S California (USA); winter range unknown.
cineritius Brewster, 1888 - Sierra de la Laguna (Victoria Mts), in Cape District (S Baja California).