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Range
 Breeds
from southeastern Alaska, southeastern Yukon, north-central and northeastern
British Columbia, and southern Mackenzie across the Prairie provinces,
through southern Ontario and Quebec to Newfoundland and Nova Scotia, and
south in the west to northern Oregon, Idaho, and Montana; in the central
and eastern United States south to the Gulf coast. Winters in the Amazon
Basin from Colombia and Venezuela south to Bolivia and southeastern Peru.
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Status
On the coast, uncommon (occasionally fairly
common) migrant and summer visitant in the Georgia Depression Ecoprovince
and the Southern Mainland Coast and locally in the Northern Mainland Coast
of the Coast and Mountains Ecoprovince; casual on Western Vancouver Island;
absent from the Queen Charlotte Islands.
In the interior, uncommon to
fairly common (occasionally common) migrant and summer
visitant in the Southern Interior and Southern Interior
Mountains ecoprovinces; uncommon in the Central Interior
Ecoprovince and rare to uncommon in the Sub-Boreal Interior
Ecoprovince from Quesnel to Prince George and Vanderhoof,
very rare elsewhere in that ecoprovince; uncommon to locally
fairly common migrant and summer visitant in the Boreal
Plains and Taiga Plains ecoprovinces; very rare in the Liard
River area of the Northern Boreal Mountains
Ecoprovince.
Breeds.
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Status
Change
No change.
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Nonbreeding
 The
Red-eyed Vireo is widely distributed across much of the southern third
of the province, from south eastern Vancouver Island and the Fraser Lowland
to the Rocky
Mountains, becoming more
scattered through central regions of the province. In the
interior, it is a species of valley bottoms and lower
mountain slopes, and is widespread in the Kootenay,
Columbia, Okanagan, and Thompson river valleys. Its
distribution extends northward across the aspen parkland of
the Cariboo and Chilcotin areas, but it becomes less
abundant north to Williams Lake, Quesnel, and Prince George.
A population in the northern Coast and Mountains, mainly
along the lower Skeena River valley, appears to be isolated
from other populations in the province. In the far north, it
has been recorded only east of the Rocky Mountain Trench. It
occurs commonly in the Peace Lowland, but becomes more
sparsely distributed in the Taiga Plains north to at least
Kwokullie Lake.
The Red-eyed Vireo has been
recorded at elevations from near sea level to 620 m on the
coast; in the interior, it occurs from the valley floor up
to 900 m elevation. It avoids areas of continuous coniferous
forest and prefers, in both coastal and interior areas,
groves of deciduous trees and shrubs in riparian habitats.
The Red-eyed Vireo occurs less frequently in suburban parks
and gardens than the Warbling Vireo.
The Red-eyed Vireo is a late
spring migrant, arriving after the leaves of deciduous trees
have emerged and when the annual horde of leaf-eating
insects is thriving. The first migrants reach the Fraser
Lowland and the southern portions of the interior in the
first week of May, and the main movement occurs from late
May to early June. First-of-year observations in the
Vancouver area range from 1 May (earliest) to 24 May
(latest) (Campbell et al. 1972a).
The mean first-arrival date in
the Okanagan valley is 25 May, with a range over 23 years of
3 May to 3 June (Cannings et al. 1987). Early migrants seem
to arrive in the west Kootenay sooner (early May) than in
the east Kootenay (late May). Provincewide, the highest
counts are from mid to late June, when most males are on
their breeding territories and sing frequently.
Autumn migration in the north
occurs in August, and most of the Red-eyed Vireos have left
the north by the end of that month. In the southern portions
of the province, migration occurs mainly in the second half
of August and in early September. Most birds have left the
province by mid-September, but a very few remain into early
October. Migration chronology in British Columbia is similar
to that reported for northern Alberta by Salt (1976), and
populations in the northeast migrate through
Alberta.
On the coast, the Red-eyed
Vireo has been recorded from 1 May to 22 September; in the
interior, it has been recorded regularly between 2 May and
25 September and irregularly to 12 October.
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Breeding
In British Columbia, the
breeding distribution of the Red-eyed Vireo is concentrated
in the southern quarter of the province, from the east coast
of Vancouver Island east
across the Southern Interior to
the Rocky Mountain Trench and north to the North Thompson
River valley. On Vancouver Island, the Red-eyed Vireo has
been found breeding at Campbell River, Duncan, and the
vicinity of Victoria, but not on the west coast. The only
confirmed breeding localities in the Central Interior and
Sub-Boreal Interior are at Williams Lake and Quesnel,
respectively. A small, relatively isolated population is
present in summer along the lower Skeena River drainage
basin, but Terrace is the only confirmed breeding locality
in that region. The Red-eyed Vireo is a relatively common
vireo in the Peace Lowland, but there are only a few
breeding records. In the Taiga Plains, although it is
regularly present from Parker Lake to Smith River, the only
breeding records are from near Fort Nelson.
The Red-eyed Vireo occurs in
summer, and probably breeds at the heads of some major
inlets along the south and central coast of the mainland.
Laing (1942) reported it at Bute Inlet, at Loughborough
Inlet, at Hagenshorg in the Bella Coola valley, and on the
estuary of the Kimsquit River. During a recent survey of the
Kitlope River, several singing males were found along the
lower reaches, but none was recorded in the mid to upper
sections. Laing (1942) believed that isolated coastal
populations reached the coast from the east by following
major river valleys, and that they probably breed
there.
This vireo reaches its highest
numbers in summer in the valleys of the Kootenay and
Columbia rivers in the Southern Interior Mountains. An
analysis of Breeding Bird Surveys shows that the mean number
of birds on interior routes decreased at an average annual
rate of 2% over the period 1968 to 1993; analysis of coastal
routes for the same period could not detect a net change in
numbers.
The Red-eyed Vireo has been
recorded breeding at elevations from near sea level to 200 m
on the coast, and from 300 to 800 m in the interior. It
breeds in forested habitats, including mixed forests (37%; n
= 30), deciduous woodlands (30%), and fragmented woodlands
in rural and suburban areas (27%). More specifically, most
nesting sites described were in riparian habitat (48%; n =
21); mature, young, or regenerating forest (19%); and
gardens (19%). On the coast, the Red-eyed Vireo is most
frequently found in mixed deciduous forests as well as
plantings of exotic trees such as Lombardy poplar and
weeping willow. It is reported infrequently from the Carry
oak-arbutus-Douglas-fir forests of southeastern Vancouver
Island, but is more common in the drier mixed forests of the
northern Gulf Islands. In the interior, this vireo frequents
woodlands of deciduous trees and mixed deciduous-coniferous
forests, especially those on moist sites.
On the coast, the Red-eyed
Vireo has been recorded breeding from 25 May (calculated) to
21 July; in the interior, it has been recorded breeding from
20 May (calculated) to 27 July.
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Nests: 
Even where the Red-eyed Vireo breeds in mixed
forests, all nests reported for British Columbia were built in deciduous
vegetation (n = 48), either trees (81%) or shrubs (19%). Like other vireos,
the Red-eyed Vireo builds a cup shaped nest suspended between diverging
or adjacent twigs. Nest materials included fine grass (74%; n = 43), bark
strips (40%), plant fibres (35%), moss (16%), lichens (16%), rootlets
(14%), plant down (14%), and other fine material, including leaves, paper,
twigs, hair, and feathers. The heights for 50 nests ranged from 1 to 15
m, with 64% between 2 and 3 m.
Eggs:
 Dates
for 47 clutches ranged from 23 May to 19 July, with 55% recorded between
16 June and 1 July. Calculated dates indicate that eggs can be found as
early as 20 May. Sizes of 43 clutches ranged from 1 to 4 eggs (1E-3,2E-2,3E-15,4E-23),
with 53% having 4 eggs. One record in British Columbia suggests that the
incubation period lies between 11 and 13 days. Peck and James (1987) give
a range of 11 to 15 days for Ontario.
Nest
Success:
Of 10 nests found with eggs and
followed to a known fate, 4 produced at least 1
fledgling.
Young: Dates for 21 broods
ranged from 20 June to 27 July, with 56% recorded between 2
July and 11 July. Calculated dates indicate that young can
occur as early as 3 June. Sizes of 18 broods ranged from 1
to 4 young (1Y-4,2Y-4,3Y-5,4Y-5), with 10 having 3 or 4
young. The nestling period is 10 to 12 days (Ehrlich et al.
1988).
Brown-headed Cowbird
Parasitism: In British Columbia, 27% of 56 nests found with
eggs or young were parasitized by the cowbird: 6 of 21 nests
on the coast, and 9 of 35 nests in the interior. There were
also 4 records of adult vireos feeding fledged cowbird
young. In Ontario, Peck and James (1987) reported parasitism
in 38% of 354 Red-eyed Vireo nests.
This vireo is well known as a
victim of the cowbird (Friedmann et al. 1977), and usually
abandons its nest if 2 or 3 cowbird eggs are laid in its
nest or if all the vireo eggs are removed by cowbirds
(Southern 1958).
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Remarks
See Lawrence (1953), Barlow and
Rice (1977), and Robinson (1981) for additional information
on the behaviour and natural history of the Red-eyed
Vireo.
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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