Identification of flycatchers in the genus Empidonax is one of the greatest identification challenges in North American birding, and will only be discussed briefly here. Subtle structural and plumage differences, calls and songs, behaviours, and habitat preferences are all important for the identification of Empidonax flycatchers. A distinctive behavioural characteristic of the Gray Flycatcher is its slow, gentle, downward wagging of the tail; no other Empidonax flycatchers mimic this behaviour, although they often quickly flick their tails downward. If desired, please refer to other technical references for a more detailed discussion of the identification criteria of the Gray Flycatcher and other members of the genus. All Empidonax species can be distinguished from other flycatchers by their small size, dull plumage, eye-rings (usually), and two whitish wing bars. Western Wood-Pewee is somewhat similar to this genus, but is larger and darker, lacks an eye-ring, has a longer primary projection, and has relatively indistinct and dull greyish wing bars.
The following members of the genus Empidonax occur within the range of the Gray Flycatcher in B.C. and could potentially cause confusion: Willow Flycatcher, Least Flycatcher, Hammond’s Flycatcher, Dusky Flycatcher, and Pacific-slope Flycatcher. Willow Flycatcher is relatively easy to differentiate from Gray Flycatcher by its slightly larger size, almost complete lack of an eye-ring, and its close association with riparian shrub thickets and wetlands (very different from the Ponderosa Pine forests that are frequented by Gray Flycatcher). Although the call notes of the two species are similar, the song of the Willow Flycatcher (a very distinctive, two-note fitz-bew) should render any singing birds easily identifiable. The Pacific-slope Flycatcher is also relatively easy to distinguish from Gray Flycatcher, and sometimes occurs in similar habitats (although usually it is restricted to riparian forests rather than dry upland pine forests). It is overall washed with yellow, with brownish on the upperparts and head (not pale greyish as in Gray Flycatcher), and has a distinctive teardrop-shaped eye-ring that flares behind the eye (the eye-ring of Gray Flycatcher is more or less even). The song of the Pacific-slope Flycatcher is also very different, being a very high-pitched series of quick, sharp notes. The call note of the Pacific-slope Flycatcher (a high, thin, whistled tseeweep) is also very different from the call note of the Gray Flycatcher. The Least Flycatcher is more similar to Gray Flycatcher but is slightly smaller, and tends to occur in deciduous woodlands and mixed riparian forests. Its song (a repeated, explosive, two-note che-bek) is very distinctive. It is more olive-toned than the Gray Flycatcher, particularly on the head and upperparts, and has more prominent, sharply-contrasting, and whiter wing bars and edges to the tertials. The lower mandible of the Least Flycatcher is mostly orange, sometimes with a diffuse dusky tip, and is very different from the sharply-contrasting black tip on the lower mandible of the Gray Flycatcher.
The two species that are most similar to the Gray Flycatcher, and often occur in the same or similar habitats, are Hammond’s Flycatcher and Dusky Flycatcher. Hammond’s Flycatcher averages slightly more olive-toned on the upperparts than Gray Flycatcher, but this is quite variable. Structurally, it is slightly larger-headed, shorter-tailed, and has a longer primary projection. The eye-ring is slightly more teardrop-shaped and flared behind the eye. The most reliable field mark for distinguishing these two species is the colour of the lower mandible. In Hammond’s Flycatcher, the lower mandible is mostly blackish with some orange at the base (sometimes up to ~1/2 of the length of the bill). The lower rmandible of Gray Flycatcher, however, is mostly orange with a small but sharply-defined black tip. The Dusky Flycatcher is structurally very similar to Gray Flycatcher but, like Hammond’s Flycatcher, is slightly more olive-tinged on the upperparts and has a more extensive and less sharply-defined black tip to the lower mandible. Differences in call notes (Dusky often gives a distinctive two-note dew-hic, although it also gives a whit that is similar to the Gray Flycatcher) and behaviour (the downward tail wagging of Gray Flycatcher is diagnostic) are the best means for distinguishing between these two species if bill colour is not visible.
| The song of the male consists of a series of rough, emphatic, two-note chuwip or jr-vip with higher-pitched, weaker, whistled teeap or tidoo notes irregularly interspersed. The rarely-heard flight call is a prolonged whit-whit-whit-whit-whit-wheak-wheak-wheat-stiddle-d-doo. Also gives an abrupt chivip and a low, whistled weew. The most commonly-heard call note is a sharp, dry whit or pit; the call note is similar to the calls of Dusky, Least, and Willow Flycatchers. When greeting at the nest, both sexes give a rapid d-d-d-d-d-d or dit-dit-dit-dit-dit call. Source: Sterling (1999); Sibley (2000) |
Courtship
Courtship and pair formation begins shortly after arrival on the breeding grounds. Male song is an important component of courtship behaviour, which also includes courtship chases and soft solicitation calls. This species appears to be monogamous through the breeding season, and often breeds in loose colonies.
Nest
The nest is constructed primarily by the female (the male sometimes assists) in mid- to late May or through June. Nest construction takes only ~3 days to complete. The nest is situated on top of a large conifer bough, on top of a horizontal tree branch, in the crotch of a tree branch, or in a small fork in the outer branches. Almost all nests are built in coniferous trees (primarily Ponderosa Pine, occasionally Douglas-fir), but some nests in the United States have been found in shrubs. Nest heights range from 1.5 to 9 m above the ground. The nest itself is a bulky (10-14 cm wide and 5-8 cm high) cup composed of grasses, shreds of bark, pine needles, sagebrush twigs, plant stems, small twigs, and leaves and is lined with plant down, hair, and feathers.
Eggs
A clutch of 3-4 eggs is laid in early to mid-June (rarely late May) and is incubated by the female for 14-16 days before hatching. This species is sometimes double-brooded and a second clutch is sometimes laid in July. The smooth, non-glossy eggs are whitish and unmarked. Eggs are found in British Columbia between late May and late July. This species is a frequent host for Brown-headed Cowbird parasitism, and several nests in B.C. have been found to be parasitized by cowbirds.
Young
The young are altricial at hatching and are largely naked, except for some sparse down on the head, wings, and back. Nestlings are tended by both parents and fledge at 15-17 days of age. After leaving the nest, the fledglings are tended by the parents for an additional 2 weeks before becoming independent. Nestlings and dependent young occur in B.C. between mid-June and mid-August.
Source: Baicich and Harrison (1997); Campbell et al. (1997); Sterling (1999)
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This species feeds almost exclusively on insects throughout the year. Most insects are captured in flight, although they are sometimes gleaned from the ground, leaves, bark, or twigs. The Gray Flycatcher is a ‘sit-and-wait’ predator that perches quietly on the lower branches of large conifers or from the top of shrubs, snags, or young trees and visually searches for potential prey. When prey is spotted, the bird flies out from its perch, captures the insect in its bill, and returns the same or a nearby perch.
Source: Sterling (1999)
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