| Species: Pacific-Slope
Flycatcher Empidonax
difficilis
Description:
A small Tyrannid
flycatcher that occurs along the coastal regions of western North
America from southern Alaska to Baja California.
Identification:
Plumage is a plain
olive brown above with yellowish throat and belly. Breast is
olive-gray. White eye ring is broad and extended. Lower jaw is
bright yellow to orange while upper jaw is dark. Two pale bars on
dark wings. Length is up to 14 cm.
Adult Male:
Similar to female. Needs to be in hand for sexing unless singing.
Adult Female:
Similar to male. Needs to be in hand for sexing.
Juvenile:
Plumage duller and grayer than adults. Indistinct wing bars are
buffy. Apparent wispiness of head feathers.
Similar Species:
Virtually identical to the Cordilleran flycatcher with which it was
once lumped together as a single species: Western flycatcher. Male
Pacific-Slope flycatchers have a single note to their call while the
male Cordilleran has two syllables. Cordillerans are a more inland
species with a preference for coniferous forests for breeding
habitat. Observers less familiar with the Empidonax flycatchers
might confuse the Pacific-slope flycatcher other species in the
genus.
Yellow-bellied flycatcher is also similar but it has a shorter tail
than the Pacific slope and its wing bars are more yellow and
brighter.
Behavior:
Like many flycatchers, this passerine sits on inconspicuous branch
and hawks for flying insects. Sometimes it will glean prey off
leaves. Shallow wing-beats give it a weak fluttering flight.
Habitat:
Found in moist deciduous woodlands or mixed forests that provides
sufficient shade. Riparian provides best breeding habitat.
Information:
Pacific-Slope
flycatchers winter in Mexico and Central America and return to the
western US and Canada during the breeding season.
Breeding females tend to build near water in a tree crotch, on cliff
ledges and sometimes human structures. They prefer shady areas and
the nest will be between 0.3 m to 13 m above ground. Nest is large
and bulky consisting of moss, lichen, grass, twigs and lined with
finer material such as fur and feathers. She will lay 3-5 eggs and
incubate them for 16 days. Hatchlings would fledge in a further 16
days. Sometimes a second brood is reared. First brood fledges in May
and the pair may nest again in July. There is a low incidence of
brood parasitism by cowbirds.
Coastal birds have been recorded from mid-March until late October.
Elsewhere in the BC province it migrates from the area earlier.
It is almost exclusively insectivorous but it has been observed
feeding on berries and seeds.
A group of flycatchers are called an “outfield”, “swatting”,
“zapper” or “zipper”.
Conservation
Status: (Least Concern)
Current global
population is estimated to be 8.3 million with little indication of
decline.
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