Notice for readers: On March 31, Neotropical Birds will be integrated into the new Birds of the World, a powerful research database offering species accounts for every species on earth. Learn more at While Birds of the World is a subscription service, we remain committed to offering this content to Neotropical Birds contributors and to those unable to pay for it through our scholarship program. Stay tuned.

Pacific-slope Flycatcher Empidonax difficilis


Aptly named difficilis. Difficult. The name “Empidonax difficilis” has had long association with the bird known as the Western Flycatcher, but this entity is actually 2 species whose breeding distribution is divided roughly along the Cascades and n. Sierra Nevada into the Pacific-slope Flycatcher west of the divide, retaining the name Empidonax difficilis, and the Cordilleran Flycatcher, taking the name Empidonax occidentalis, found to the east to the Rocky Mountains and south in mountains throughout most of Mexico.  The species' biology is undoubtedly similar to that of other Empidonax species.  Molt occurs primarily on the wintering grounds.

Help complete this species

There are many ways to contribute—we need species information, photographs, audio, video, translations, maps, distribution data, and bird sightings. There's a role for everyone!

Learn more

© Thomas G. Sander

  • Year-round
  • Migration
  • Breeding
  • Non-Breeding

Recommended Citation

Pacific-slope Flycatcher (Empidonax difficilis), In Neotropical Birds Online (T. S. Schulenberg, Editor). Cornell Lab of Ornithology, Ithaca, NY, USA. retrieved from Neotropical Birds Online: