The Cordilleran flycatcher (''Empidonax occidentalis'') is a small insect-eating

bird Birds are a group of warm-blooded vertebrates constituting the class Aves (), characterised by feathers, toothless beaked jaws, the laying of hard-shelled eggs, a high metabolic rate, a four-chambered heart, and a strong yet lightweig ...

. It is a small ''

Empidonax The genus ''Empidonax'' is a group of small insect-eating passerine birds in the tyrant flycatcher family, the Tyrannidae. The genus name ''Empidonax'' is from Ancient Greek ''empis'', "gnat", and ''anax'', "master". Most of these birds are ver ...

'' flycatcher, with typical length ranging from 13 to 17 cm. Adults have olive-gray upperparts, darker on the wings and tail, with yellowish underparts; they have a conspicuous teardrop-shaped white eye ring, white wing bars, a small bill and a short tail. Many

species In biology, a species is the basic unit of classification and a taxonomic rank of an organism, as well as a unit of biodiversity. A species is often defined as the largest group of organisms in which any two individuals of the appropriate s ...

of this

genus Genus ( plural genera ) is a taxonomic rank used in the biological classification of living and fossil organisms as well as viruses. In the hierarchy of biological classification, genus comes above species and below family. In binomial nom ...

look closely alike. The best ways to distinguish species are by voice, by breeding habitat, and by range. This bird is virtually identical to the Pacific-slope flycatcher. These two species were formerly considered a single species known as western flycatcher. The species were split by the American Ornithologists’ Union in 1989. The Pacific-slope flycatcher is a breeding bird of the Pacific Coast forests and mountain ranges from

California California is a state in the Western United States, located along the Pacific Coast. With nearly 39.2million residents across a total area of approximately , it is the most populous U.S. state and the 3rd largest by area. It is also the m ...

Alaska Alaska ( ; russian: Аляска, Alyaska; ale, Alax̂sxax̂; ; ems, Alas'kaaq; Yup'ik: ''Alaskaq''; tli, Anáaski) is a state located in the Western United States on the northwest extremity of North America. A semi-exclave of the U.S. ...

; the Cordilleran is a breeding bird of the

Rocky Mountains The Rocky Mountains, also known as the Rockies, are a major mountain range and the largest mountain system in North America. The Rocky Mountains stretch in straight-line distance from the northernmost part of western Canada, to New Mexico ...

. They have different songs and calls. Cordilleran flycatchers' preferred breeding habitat is

pine A pine is any conifer tree or shrub in the genus ''Pinus'' () of the family Pinaceae. ''Pinus'' is the sole genus in the subfamily Pinoideae. The World Flora Online created by the Royal Botanic Gardens, Kew and Missouri Botanical Garden accepts ...

oak An oak is a tree or shrub in the genus ''Quercus'' (; Latin "oak tree") of the beech family, Fagaceae. There are approximately 500 extant species of oaks. The common name "oak" also appears in the names of species in related genera, notably ''L ...

or coniferous forest, usually near running water. They make a

cup nest A bird nest is the spot in which a bird lays and incubates its eggs and raises its young. Although the term popularly refers to a specific structure made by the bird itself—such as the grassy cup nest of the American robin or Eurasian bla ...

on a fork in a tree, usually low in a horizontal branch. Females usually lay two to five eggs. These birds migrate to

Mexico Mexico (Spanish: México), officially the United Mexican States, is a country in the southern portion of North America. It is bordered to the north by the United States; to the south and west by the Pacific Ocean; to the southeast by Guatema ...

for the winter, where the Mexican central-southern birds are

resident Resident may refer to: People and functions * Resident minister, a representative of a government in a foreign country * Resident (medicine), a stage of postgraduate medical training * Resident (pharmacy), a stage of postgraduate pharmaceuti ...

. The non-resident birds are on the western coast from Jalisco northwards, and then to inland regions, in a corridor strip on the western flank of the

Sierra Madre Occidental The Sierra Madre Occidental is a major mountain range system of the North American Cordillera, that runs northwest–southeast through northwestern and western Mexico, and along the Gulf of California. The Sierra Madre is part of the American ...

. The Cordilleran flycatcher waits on an open perch of a shrub or low branch of a tree and flies out to catch insects in flight (

hawking Hawking may refer to: People * Stephen Hawking (1942–2018), English theoretical physicist and cosmologist * Hawking (surname), a family name (including a list of other persons with the name) Film * ''Hawking'' (2004 film), about Stephen Ha ...

), and also sometimes picks insects from foliage while hovering (

gleaning Gleaning is the act of collecting leftover crops from farmers' fields after they have been commercially harvested or on fields where it is not economically profitable to harvest. It is a practice described in the Hebrew Bible that became a legall ...

). The song includes notes represented as ''pseet'', ''ptsick'', ''seet'' usually sung rapidly together. The ''ptsick'' or ''ptik'' note has the first syllable higher-pitched than the second—the only difference from the Pacific-slope flycatcher's song (Sibley 2000). The male's typical position call is a loud and distinctive ''pit pete'' or ''tse-seet'', but some give a "rising ''tsweep''" or a "slurred ''tseeweep'', like the calls of Pacific-slope flycatchers (Sibley 2000).

References

External links

Videos, photos and sounds
- Internet Bird Collection

- VIREO ttp://vireo.acnatsci.org/species_image.php?species=Empidonax+occidentalis Photo-High Resbr>PhotoArticle
fwp.mt.gov (Montana Fish, Wildlife & Parks) {{Taxonbar, from=Q543325 Cordilleran flycatcher Native birds of Western Canada Native birds of the Rocky Mountains Native birds of the Western United States Birds of the Great Basin Birds of the Rio Grande valleys Birds of Mexico Birds of the Sierra Madre Occidental Cordilleran flycatcher Cordilleran flycatcher