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Range
 Resident
from coastal southern and southeastern Alaska south along
the Pacific coast to central California and the southern
portions of the interior of British Columbia. Breeds from
northern British Columbia through the forested parts of
Canada to Newfoundland, south into northwestern Oregon and
northern Idaho in the west, and Georgia and Tennessee in the
east. Winters within, but mostly south of, the breeding
range, including the southern United States. Also occurs in
Eurasia and northwestern Africa.
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Status
On the coast, fairly common to
common resident in southwestern British Columbia, including
the Georgia Depression Ecoprovince and Western Vancouver
Island, Queen Charlotte Islands, and Southern Mainland Coast
of the Coast and Mountains Ecoprovince, becoming uncommon
along the Northern Mainland Coast of that ecoprovince,
including offshore islands other than the Queen Charlotte
Islands.
In the interior, fairly common
resident in the Southern Interior and the Southern Interior
Mountains ecoprovinces; uncommon migrant and summer
visitant, and locally very rare throughout the year, in the
Central Interior and Sub-Boreal Interior ecoprovinces; very
rare migrant and summer visitant to the Northern Boreal
Mountains and Boreal Plains ecoprovinces; casual in the
Taiga Plains Ecoprovince.
Breeds.
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Status
Change
Munro and Cowan (1947) did not
include the Cariboo and Chilcotin areas of the Central
Interior, or northeastern British Columbia north of the
Peace Lowland, within the range of the Winter Wren. It is
now known to be a local resident at lower elevations and a
fairly common summer visitant in the subalpine forests of
the Central Interior, and a scarce summer visitant to the
Taiga Plains and eastern Northern Boreal
Mountains.
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Nonbreeding
 The
Winter Wren is widely distributed in forested habitats
throughout much of the province. It is most numerous and
occurs throughout the year in the dense coniferous forests
along the coast. East of the coastal mountains, it occurs in
forested areas in much of the southern and central portions
of the interior east to the Rocky Mountains and north in
local populations to the Tatshenshini River, Liard River,
and Fort Nelson areas. It is sparsely distributed in
northern regions.
The highest numbers in winter
occur in the Georgia Depression and adjacent mountain
slopes. Root (1988) notes that the Winter Wren winters
mainly in areas that receive an annual precipitation of at
least SO cm, which occurs on most of the coast.
On the coast, the Winter Wren
has been recorded at elevations from sea level to 1,S00 m.
In the interior, it has been recorded up to 2,250 m in the
Southern Interior Mountains and 1,950 m in the Central
Interior. Although it uses a wide range of habitats, it is
seldom found more than a few metres above ground. On the
coast, the Winter Wren prefers forested habitats where the
forest floor is shaded and has "old-growth" characteristics
such as ground litter and fallen trees in various stages of
decomposition, especially where the skeletons of upturned
root-masses are a prominent landscape feature, and where
mosses are the dominant ground vegetation. It also occurs in
areas of dense brush and shrubs associated with the edges of
human-made corridors, in thickets at the edges of wetlands,
and in more open forests with a shrubby ground layer. On
treeless offshore islands, it frequents dense, wind-pruned,
shrubby vegetation. Along coastal beaches, it uses piles of
driftwood above the upper tideline as foraging
habitat.
 On
the west coast of Vancouver Island, Bryant et al.
(1993) found the Winter Wren present in 96%:
(n = 71) of old-growth plots, 69% (n = 36) of
50- to 60-year-old forest plots, 64% (n = 36) of 30-
to 35-year-old forest plots, and less than 25% of plots in
forests that were less than 21 years old. In Pacific Rim
National Park, on the other hand, it was common in a 2-year
old clearcut and in a 24-year-old forest replanted after
logging (Roe 1974).
In the interior, the Winter
Wren occurs in more dispersed populations, especially where
old-growth forest occurs. At lower elevations, dense woods
in moist ravines or gulleys that have thick underbrush are
used. At higher elevations, dense spruce and fir forests are
used, including krummholz habitat at the timberline. An
exception is the Douglas-fir-ponderosa pine forests of the
southern valleys, where the Winter Wren occurs mainly in
migration; even there it may be resident in shaded, cooler
gullies where western redcedar is present.
The Winter Wren, a versatile
little bird, also occurs at the edges of clearings of
powerline rights-of-way, in logging slash, and in shrubbery
of parks, golf courses, and gardens. During the winter it
finds sheltered roosting sites in old woodpecker nest
cavities, bird and mammal burrows, abandoned or open
outbuildings, and even crevices in occupied
homes.
Most of the population along
the coast and in the Southern Interior and Southern Interior
Mountains is resident, but elsewhere in the province this
wren is migratory. Spring migration is not discernible in
the Georgia Depression and southern regions of the Coast and
Mountains, because of the presence of resident birds. On the
Northern Mainland Coast, spring migration seems to occur in
April. In the Southern Interior there is an increase in
observations between January and April, which may reflect
increased numbers due to spring migration, but a steep
decline in records between April and May certainly reflects
a movement of wrens from valley bottom localities to
higher-elevation forests. In the Southern Interior
Mountains, the first spring migrants arrive in March, but
April probably sees the greatest movement. The small number
of records for the northern regions of the province
indicates that April is the month of spring arrival
there.
In the interior, the Winter
Wren migrates out of regions north of about latitude
52°N in autumn, roughly the latitude of Williams Lake.
It also moves away from high-elevation mountain slopes to
winter in protected, low-elevation riparian habitats (e.g.,
Cannings et al. 1987). In the northern half of the province,
southward migration begins by the end of July and is
essentially complete by the end of August, although late
migrants have been found in October in the Peace Lowland and
in November near the Yukon border at Redfish Creek. In the
Central Interior, the main departure occurs from August to
October, although a few birds overwinter. In the Southern
Interior Mountains, migrants leave mainly in September and
October. Southern populations that breed near the timberline
in the interior move to lower elevations by mid September.
It is unknown whether or not some interior populations
migrate to the coast for the winter.
Autumn migration in coastal
areas is difficult to discern. For example, although there
seem to be higher numbers in winter than in summer in the
Georgia Depression, the extent or timing of migration cannot
be determined from our data.
Along the coast and in the
southern third of the interior, the Winter Wren occurs
throughout the year; in the central interior, it has been
recorded regularly from 16 April to 23 October; in the
northern third of the interior, it has been recorded
regularly from 23 April to 10 September, and as late as 18
November.
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Breeding
The Winter Wren breeds across
much of the southern two-thirds of the province, including
the Queen Charlotte Islands, Vancouver Island, other
offshore islands, and the mainland coast, east across the
southern portions of the interior to the Flathead River
valley and north to the Skeena and Nechako river valleys.
The northernmost breeding records are from Terrace,
Smithers, Pine Pass, and Williston Lake. Nests with eggs or
young have not been recorded north of latitude 56°N.
Although we know of no confirmed breeding records, the
Winter Wren probably breeds north to the Yukon border, as
suggested by Godfrey (1986).
The Winter Wren reaches its
highest numbers in summer in the Georgia Depression and
Coast and Mountains. An analysis of Breeding Bird Surveys
for the period 196S to 1993 could not detect a net change in
numbers on either coastal or interior routes.
The Winter Wren has been
reported breeding from near sea level to 2,100 m elevation.
Most breeding sites were described as forest (78%; n
= 171) or human-influenced habitats (19%). In forested
habitats, coniferous forest was most frequently used (41%;
n = 103), followed by mixed forest (22%) and
human-made corridors through forest (18%). Both mature
forests (26%; n = 76) and young forests (26%) were
used, as were roadsides (20%) and backyards or farmyards
(12%).
The Winter Wren has been
recorded breeding in British Columbia from 23 March to 12
September.
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Nests: 
Nests were found mainly in
living and dead coniferous or deciduous trees (52%; n
= 122) and banks and cliffs (24%). A few were found in
buildings and sheds. Unusual nest sites included shrubs, a
bridge, an abandoned automobile, and standing totem poles in
an abandoned Indian village.
Most nests were built in a
cavity. Specific nest sites included natural cavities and
those excavated by woodpeckers in living and dead trees or
stumps (33%; n = 106), among the roots of overturned
trees (26%), under an overhang in a soil bank or cliff or an
overhang of a building (26%), attached to rafters, under
loose bark or in bark crevices, suspended above ground in
vertically oriented branches and sticks beneath clumps of
shrubby vegetation, attached to a tree branch, in seabird
burrows, and in a pair of snowshoes; 1 nest was found in a
nest box.
The globular nest is usually
well concealed and is composed of moss, twigs, grass,
leaves, feathers, hair, plant fibres, rootlets, needles,
shreds of rotten wood, and similar soft debris. The heights
for 86 nests ranged from ground level to 7.0 m, with 61%
between 0.8 and 1.8 m.
Eggs:
Dates for 61 clutches ranged
from 23 March to 29 August, with 530 recorded between 20
April and 5 June. Sizes of 53 clutches ranged from 1 to 7
eggs (1E-7, 2E-3, 3E-3, 4E-7, 5E-17, 6E-13, 7E-3), with 57%
having 5 or 6 eggs. The incubation period is variously
stated to be 14 to 16 days (Bent 194S), 14 to 17 days
(Harrison 1979), 11? to 16 days (Ehrlich et al. l9S8), and
14 to 20 days (Kluijver et al. 1940). Armstrong
and
Whitehouse (1977) state that
incubation periods longer than 16 days are probably the
result of delayed or irregular brooding. See further
comments on incubation period in REMARKS.
Nest
Success:
Of 7 nests found with eggs and
followed to a known fate, 2 produced at least 1
fledgling.
Young: Dates for 30 broods
ranged from 6 April to 12 September, with 52% recorded
between 13 May and 14 June. Brood size ranged from 1 to 7
young (1Y-2, 2Y-6, 3Y-3, 4Y-7, 5Y-9, 7Y-3), with 53% having
4 or 5 young. The nestling period is 15 to 20 days (Harrison
1979).
Ehrlich et al. (1988) suggest
that the Winter Wren may produce 2 broods a year, and some
populations in British Columbia probably do so.
Double-brooding can be established positively only where the
nesting birds are banded or otherwise individually
identifiable; however, records from the Queen Charlotte
Islands suggest that at least part of that is land
population nests twice in a summer. Records of 2 broods out
of the nest on 29 May at Anthony Island and a pair nest
building at Masset on 4 April establish the timing of the
first broods, while a pair feeding nestlings at Rose Harbour
on 26 August and a similar record for Hippa Island on 12
August suggest a second brood. There are similar data for
Vancouver Island and southern portions of the
interior.
Brown-headed Cowbird
Parasitism: Cowbird parasitism was not found in British
Columbia in 83 nests recorded with eggs or young. Friedmann
(1963), Friedmann et al. (1977), and Friedmann and Kiff
(1985) do not list any occurrences for North
America.
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Remarks
Two subspecies of Winter Wren
occur in the province: T. t. pacificus west of the
Rocky Mountains (Munro and Cowan 1947; American
Ornithologists' Union 1957) and T. i. hiemalis in the
Boreal Plains and possibly other boreal regions along the
Yukon border. See Oberholser (1902,1920) for more details on
subspecies.
The Winter Wren is considered
"exceptional and perhaps unique as a North American
passerine which has successfully extended its range from
North America into Asia, Europe, and North Africa"
(Armstrong and Whitehouse 1977). These authors discuss
variations in behaviour that lead to alterations in the
apparent incubation period. They cite Kluijver et al. (1940)
for the finding that in April and May incubation usually
begins on the day the last egg is laid, whereas in June and
July it often starts before the clutch is complete, thus
leading to variation in incubation period. Some wrens may
even begin incubation upon laying the first egg: 1 nest
recorded in British Columbia was discovered on 23 May with a
full clutch of 7 eggs. The hatching of the first nestling
was noted on 26 May and proceeded with 1 egg hatching daily
until 31 May. The nest was checked daily until 13 June, when
all 7 young were still present.
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Located
at:
675 Belleville Street,
Victoria, British Columbia,
CANADA
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All rights reserved
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Nests