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Range
 Resident
from southeastern Alaska south along the coast to Baja California;
in the interior from southern British Columbia south through Idaho,
Utah, New Mexico, southeastern Colorado, and western Texas to southeastern
Coahuila and Mexico City.
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Status
Uncommon to fairly common resident on
the south coast including Vancouver Island. Rare to uncommon resident
on the northern mainland coast. Absent from the Queen Charlotte
Islands. Rare to uncommon local resident in the central-southern
interior; very rare in the west and east Kootenays. Breeds. |
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Status
Change
No change. |
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Nonbreeding
The Western Screech-Owl occurs year round
on Vancouver Island and on the adjacent mainland coast throughout
the Fraser Lowlands to Hope. It probably also occurs as a resident
along the northern mainland coast, west of the Coast Ranges, north
to at least Terrace. In the interior, it is a local resident below
600 m elevation from Adams Lake and Shuswap Lake south through the
Okanagan valley. Elsewhere, it is very rarely encountered.
The Western Screech-Owl is essentially
non-migratory. On the coast, it is found in all woodland habitats,
but it prefers mixed deciduous/coniferous forests, usually near
a source of water. In the interior, most birds are found in deciduous
woodlands along lakeshores and streams. It roosts in tree cavities,
nest boxes, buildings, trees, vines, and crevices in cliffs. Hooting
has been recorded every month on the coast but begins in earnest
in February; in the interior, hooting begins in early March. |
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Breeding
The Western Screech-Owl breeds on southern
and eastern Vancouver Island, the Gulf Islands, and the adjacent
mainland coast, including the Fraser Lowlands to Chilliwack, north
to Kitimat, including coastal islands (e.g. the Goose Group; Guiguet
1949). In the interior, it is known to breed only in the southern
Okanagan valley.
This owl nests in open deciduous and
coniferous woods and riparian habitats including rivers, creeks,
marshes, bogs, lakes, and large ponds. In urban and residential
areas it frequents orchards, parks, and gardens. Most nests were
situated near water and none were found above 540 m elevation. Much
of the information that follows is the result of nest box programs. |
| Nests: 
Most nests (87%; n=62) were situated
in wooden nest boxes (61%) and natural cavities (26%) of black cottonwood,
red alder, Douglas-fir, western redcedar and western hemlock. All
nest tree diameters were greater than 25 cm at breast height. Other
nests (13%) were in cavities excavated by Pileated Woodpeckers and
Northern Flickers.
Heights for 43 nests ranged from 1.2
to 12.2 m, with 65% recorded between 3.0 and 4.6 m. Depths of 3
tree cavities ranged from 30 to 36 cm; diameters of 2 entrance holes
were 15 cm each. Nest materials were usually absent, but a few contained
sparse collections of wood chips, feathers, moss, and mammal fur.
Eggs:
Dates for 49 clutches ranged from 17
March to 31 May, with 53% recorded between 9 and 21 April. Sizes
for 51 clutches ranged from 1 to 5 eggs (1E-4, 2E-20, 3E-17, 4E-9,
5E-1) with 73% having 2 or 3 eggs. Incubation period is probably
similar to that of O. asio which has variously been reported within
range of 21 to 30 days (Bent 1938) but averages 26 days (Sherman
1911).
Young:
Dates for 53 broods ranged from 19 April
to 21 August, with 51% recorded between 8 May and 3 June. Sizes
for 46 broods ranged from 1 to 5 young (1Y-11, 2Y-16, 3Y-13, 4Y-5,
5Y 1), with 63% having 2 or 3 young. Fledging period, also for Oasio,
ranges from 35 to 42 days (Bent 1938). |
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Remarks
There are several unconfirmed sightings and
records of birds heard on the Queen Charlotte Islands. None are convincing,
including a published occurrence by Patch (1922) who states ". . . believe
I heard [at Tow Hill] . . . in woods bordering muskeg." Godfrey
(1986) shows the range of the Western Screech-Owl extending north in the
interior "rarely" to the Vanderhoof region (see Taverner 1919), however
we are unaware of any interior records with convincing details north of
Adams Lake.
The taxonomy of screech owls in North and Middle
America remains confused. The American Ornithologists' Union (1957) lists
18 subspecies of screech-owls in North America. The Western Screech-Owl
was formerly considered part of the Screech Owl (Otus asio) complex
(American Ornithologists' Union 1957), but was separated from the eastern
species on the basis of differences in vocalizations and behaviour as
an "incipient species" (Marshall, J.T. 1967; American Ornithologists'
Union 1983). Hekstra (1982) describes the subspecies of all North American
Otus . The Western Screech-Owl is also known as Kennicotts' Screech-Owl. |
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This
information was scanned from The Birds of British Columbia (Campbell et
al.), Volume II, pages 358-359. Volumes I, II and III of The Birds of British
Columbia can be ordered electronically at: 
Nests