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Range
 Breeds
from central Alaska and southern Yukon east to south-central
Manitoba, North Dakota, and Kansas, south to Baja
California, Guatemala, and Honduras. Winters from southern
Central America to Peru and Bolivia.
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Status
On the coast, an uncommon to
fairly common migrant and summer visitant to the Georgia
Depression Ecoprovince, becoming rare to uncommon elsewhere
on the coast, including Western Vancouver Island. Absent
from the Queen Charlotte Islands.
In the interior, an uncommon to
fairly common (locally common) migrant and summer visitant
throughout the southern and central regions of the province
north to the Boreal Plains Ecoprovince; further north and
west it becomes uncommon.
Breeds.
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Status
Change
No change.
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Nonbreeding
The Western Wood-Pewee is
widely distributed in forested areas throughout much of the
southern two-thirds of the province. It is sparsely
distributed in the Northern Boreal Mountains and Taiga
Plains ecoprovinces. There are also large areas on the coast
where the species has not been reported, including much of
the exposed coastal areas of Western Vancouver Island, most
of the southern and northern regions of the Coast and
Mountains Ecoprovince between Rivers Inlet and Prince
Rupert, and all of the Queen Charlotte Islands. In the
interior, there is a large area on both sides of the Rocky
Mountain Trench from Mackenzie north to Lower Post where
records of the species are lacking.
The Western Wood-Pewee occurs
from near sea level to about 1,900 m elevation. It frequents
a wide variety of open coniferous, deciduous, and mixed
forests, usually near water or around the edges of
clearings. Habitats include cottonwood riparian lowlands,
beaver meadows, open coniferous forests, aspen and birch
parklands, Carry oak woodlands, burns, brushy meadows,
swamps, orchards, farmsteads, and gardens.
Rand (1944) found the Western
Wood-Pewee common at Muncho Lake in the scattered spruces of
old alluvial fans. In the Peace River area, Cowan (1939)
found it abundant in mature aspen forests. In the Okanagan
valley, it is most common in ponderosa pine forests,
orchards, gardens, and deciduous stands around lakes below
1,000 m (Cannings et al. 1987). In Mount Revelstoke and
Glacier national parks, Van Tighem and Gyug (1983) report
the highest densities in mixed forests and wetlands in the
Interior Cedar-Hemlock forest. In the Smithers area, Polar
(1993) found the highest densities for this species in
mature aspen stands, although it also occurred in old and
mixed seral stages. Favourite perches for hunting and
calling are the dead lower branches of aspens or the tops of
smaller trees (Verbeek 1975).
In the Coast and Mountains
(Western Vancouver Island), Georgia Depression, Southern
Interior, and Southern Interior Mountains ecoprovinces,
early spring migrants may arrive in the third or fourth week
of April, with a peak movement occurring about the second or
third week of May. By early May, migrants have reached the
Central Interior and Sub-Boreal Interior ecoprovinces,
reaching the Boreal Plains by the second week of May; the
main movement peaks in those areas by about the third week
of that month. Further north, birds arrive about the last 2
weeks of May.
In the north, the autumn
migration begins shortly after the young are on the wing,
and most birds have left by early September. In the south,
both on the coast and in the interior, the main movement
peaks in late August and early September. By mid-September
most birds have left the province, and all birds have gone
by the second week of October.
Migrants are occasionally
grounded by poor weather. In late May 1991,50 Western
Wood-Pewees were reported from the Nelson and Castlegar
area, including a single flock of 25 birds.
On the coast, the Western
Wood-Pewee has been reliably recorded in the province from
22 April to 3 October; in the interior, it has been recorded
from 23 April to 30 September.
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Breeding
The Western Wood-Pewee has a
widespread breeding distribution from southeastern Vancouver
Island east across the province to the west Kootenay and
north through the Central Interior to the Skeena River
valley in the west and the Peace River area of the Boreal
Plains in the east. Breeding records are lacking from
Western Vancouver Island, most of the east Kootenay region,
all but the extreme southern portions of the Sub-Boreal
Interior, and the Northern Boreal Mountains and Taiga
Plains. However, the species probably breeds throughout its
summer range in the province.
The highest numbers for the
Western Wood-Pewee in summer occur in the southern portions
of the Sub-Boreal Interior (Rising and Schueler 1980). An
analysis of Breeding Bird Surveys for the period 1968
through 1993 shows that the number of birds on interior
routes has decreased at an average annual rate of 1%;
analysis of coastal routes for the same period could not
detect a net change in numbers. As early as the mid-1940s,
however, Pearse (1946) noted that the Western Wood-Pewee was
"seldom heard now" in the vicinity of Comox on Vancouver
Island.
The Western Wood-Pewee has been
recorded breeding from near sea level to 1,700 m elevation.
It breeds in forested habitats (45%; n = 170) and
human-altered habitats (39%) such as gardens, farms,
orchards, parks, playgrounds, campgrounds, and
transmission-line corridors. The majority of nests were
reported from the Southern Interior, where there was
frequent use of gardens close to water. Similar sites were
also used in the Georgia Depression and Southern Interior
Mountains, where about one-third of all nests were found in
altered habitats. These data may be biased towards nests
that are more easily found in sparse growth and semi-open,
agricultural areas rather than nests that are in forests or
woodlands. In the north, this species frequently nests near
beaver ponds. Occasionally mixed woods are used for
nesting.
Most nests (43%; n=142) were
reported from cultivated environments. The remaining nests
were associated with 24 other classes of open habitat,
including swamps, marshes, beaver ponds with drowned trees,
small lakes, rangeland, sagebrush, and talus.
Cannings et al. (1987) state
that breeding wood-pewees in the Okanagan were most abundant
in aspen groves around ponds and lakes, often preferring
areas with water-killed trees. In Kootenay National Park,
breeding habitat is restricted to open Douglas-fir
bottomlands along the Kootenay River and mixed successional
forests of spruce, aspen, and alder (Poll and Porter
1984).
On the coast, the Western
Wood-Pewee has been recorded breeding from 25 May to 14
August; in the interior, it has been recorded from 20 May to
17 August.
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Nests: 
All nests (n = 198) were found
in trees, usually living but occasionally dead. Most nests
(75%) were found in deciduous trees; trembling aspen (17%),
poplar (15%), and black cottonwood (7%) were the most
frequently reported native species. A wide variety of garden
and orchard species were also used. In the Boreal Plains and
Central Interior, up to 50% of the nests were found in
trembling aspen, while in the Southern Interior ponderosa
pine and poplar were reported with equal frequency (19%; n =
120), followed by trembling aspen (13%).
Almost all nests (97%; n = 172
) were situated on horizontal tree branches, usually well
out from the trunk; 25% were in natural forks or saddled the
limb .
The heights of 187 nest s
ranged from 0.4 to 18 m above the ground (or water), with
65% between 2.4 and 8.0 m.
Nests were elegantly
constructed cups composed mainly of grasses (75%). Other
nest materials included lichens (26%), animal hair (15%),
feathers (9%), bark strips (6%), and leaves (2%). In
addition, mosses and plant down were used, and cobwebs were
often incorporated into the outer surface of the basic
structure. Lining material consisted of grasses, plant
fibres and down, mosses, bark strips, and
lichens.
Eggs:
Dates for 136 clutches ranged
from 20 May to 5 August, with 50% recorded between 20 June
and 8 July. Calculated dates indicate that eggs could be
found as earl y as 17 May. Sizes of 90 clutches ranged from
1 to 5 eggs (1E-1,2E-l9, 3E-45,4 E-24,5 E-1), with 77%
having 3 or 4 eggs. The incubation period is 12 or 13 days
(Ehrlich et al. 198 8).
Nest
Success:
Of 21 nests found with eggs and
followed to a known fate, 10 produced at least 1 fledgling.
Young: Dates for 94 broods
ranged from 20 June to 17 August, with 52% recorded between
8 and 22 July. Calculate d date s indicate that young could
be found as earl y as 29 May . Sizes of 59 broods ranged
from 1 to 5 young (1Y-8, 2Y1 0, 3Y-27, 4Y-13, 5Y-1), with
68% having 3 or 4 young. The nestling period is 14 to 18
days (Ehrlich et al. 1988).
Brown-headed Cowbird
Parasitism: In British Columbia, 6% of 139 nests found with
eggs or young were parasitized by the cowbird. Interior nest
parasitism was 5% (n = 133); only 1 of 6 coastal nests was
parasitized. Friedmann and Kiff (1985) list only 8 instances
of the Western Wood-Pewee serving as host for the cowbird in
North America; 1 was from British Columbia (Friedmann
1934).
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Remarks
Two subspecies occur in Canada:
C. s. velici Coues and C. s. saturatus Bishop,
the latter being the race found in British Columbia
(American Ornithologists' Union 1957).
All records of this species in
British Columbia earlier than 22 April (see Cannings et al.
1987) and later than 3 October have been excluded from the
analysis because they lack convincing details.
A Western Wood-Pewee banded as
a fledgling in Vernon in May 1934 returned in May 1935 and
"nested not only in the same apple tree but on top of its
old nests (Fowle 1940). Bent (1942) provides additional
life-history information.
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Located
at:
675 Belleville Street,
Victoria, British Columbia,
CANADA
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Copyright © Royal BC Museum
All rights reserved
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Nests