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Range
Resident
from southeastern Alaska, northwestern and central British Columbia,
southwestern Alberta, western Montana, Wyoming, western Colorado,
and New Mexico south to southern California, Arizona, southwestern
Texas, and the Middle American highlands to Nicaragua.
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Status
On the coast, uncommon to locally fairly
common resident, including Vancouver Island and the Queen Charlotte
Islands.
In the interior, uncommon to locally
fairly common resident across the Southern Interior and Southern
Interior Mountains ecoprovinces; rare to fairly common in the Cariboo
and Chilcotin areas of the Central Interior Ecoprovince; rare to
uncommon in the Sub-Boreal Interior Ecoprovince; very rare in the
Peace Lowland of the Boreal Plains Ecoprovince and in the Northern
Boreal Mountains Ecoprovince. Absent from the Taiga Plains Ecoprovince.
Locally, common to very common during irruptive movements in autumn
and winter, across the southern portions of the province.
Breeds. |
Status
Change
In 1947 the Steller's Jay was unknown
in the interior of the province north of latitude 56°N or in
the Peace River drainage basin (Munro and Cowan 1947). The first
evidence of its entry into the Peace River region is a specimen
taken on the banks of East Pine River, 64 km west of Daw son Creek
Robin 1955). While it has not become a regular occupant of the region,
it has recently been observed in the area between Chetwynd and Fort
St. John and north as far as Rose Prairie, areas formerly occupied
only by the Blue Jay. More recently it has extended its range into
the Northern Boreal Mountains, where in 1959 it was recorded at
Marion Creek in the Spatsizi Plateau. In 1972 it was discovered
at Cassiar and along the Haines Highway, between Miles 52 and 54. |
Nonbreeding
The
Steller's Jay is widely distributed throughout south coastal British
Columbia, including Vancouver Island, but is less abundant on the
northern mainland of the
Coast and Mountains Ecoprovince, the
Queen Charlotte Islands, and other offshore islands. In the interior,
it has a widespread distribution through the Southern Interior and
Southern Interior Mountains, but becomes less numerous in the Central
Interior, the Sub-Boreal Interior to the Cassiar Mountains, and
northwest to the Tatshenshini Basin. East of the Rocky Mountains,
it occurs in the Peace Lowland of the province. It has not yet been
reported from the Taiga Plains in the far northeastern corner of
the province.
The highest numbers in winter occur on
southeastern Vancouver Island and the Fraser River delta regions
of the Georgia Depression, and on Western Vancouver Island
The Steller's Jay occurs at elevations
from near sea level to 1,500 m on the coast, and from the valley
bottoms around 300 m up to 2,150 m in the interior. It frequents
a wide range of coniferous and mixed coniferous-deciduous forest
communities, from the Coastal Douglas-fir and Mountain Hemlock zones
on the coast to the Ponderosa Pine and Engelmann Spruce-Subalpine
Fir zones of the interior. In the far north and northeast, it inhabits
the Boreal White and Black Spruce Zone.
Although the Steller's Jay can be sympatric
with the Gray Jay, especially on winter ranges, it prefers lower
elevations than the Gray Jay. For example, in the Southern Interior
Mountains from September to March, the Steller's Jay is primarily
confined to the interior cedar-hemlock forests at a mean elevation
of 884 m ill = 221), while the Gray Jay is found in the Engelmann
spruce-subalpine fir forests at a mean elevation of 1,280 m (n =
47) (J.G. Woods pers. comm.). The Steller's Jay usually frequents
open woodlands, edges of clearings, transmission line rights-of-way,
breaks in the forest, and riparian growth along waterways. Other
habitats include swamps, bogs, second-growth forests, and brushy
clearcuts. In dense forests, it occurs only along the edges. The
Steller's Jay also readily uses human-made habitats such as well-treed
residential neighbourhoods, parks, golf courses, nut-orchards, cemeteries,
campgrounds, picnic grounds, gardens, road rights-of-way, and garbage
dumps. It is often seen on the gravelled shoulders of highways through
forested regions.
Although the Steller's Jay is considered
a resident throughout its range, it appears to be an attitudinal
migrant. This seasonal movement is more regular in the interior
than on the coast, but even there it can be erratic, sometimes starting
as early as July. It usually begins in August and reaches a peak
in September or October. In the Cariboo and Chilcotin areas, and
in the Okanagan (Cannings et al. 1987), this jay may appear at valley
bottom bird feeders in late September and leave by early April.
In the east Kootenay, the movement to the valley bottom is noticeable
in September; by March the birds begin returning to their nesting
elevations. The same behaviour can be found on the south coast.
Based on banding returns, individual Steller's Jays are also known
to wander erratically over considerable distances (Table 6).
There is also evidence for at least a
limited north-south migration. In the autumn of 1927, Steller's
Jays were captured and banded at Indianpoint Lake (McCabe and McCabe
1928). The banding revealed that what was believed to be a small
resident group involved a steady turnover of individuals as part
of a latitudinal movement. Each jay was present at the banding site
for an average of 3 days before moving on. One banded bird was recovered
2 weeks later 200 km south, at Vavenby. In another instance, an
immature bird banded near Barkerville was recovered 150 km to the
south, near Canim Lake (Table 6).
Birds in the northern ecoprovinces appear
to move out of those regions, while in the southern ecoprovinces
numbers appear relatively constant or build through the winter.
The southern areas could be receiving birds from the north as well
as birds moving into the valley bottoms from their higher-elevation
breeding areas.
Evidence of a latitudinal movement is
strongest on the coast. There the number of records and the total
birds seen reach their highest levels in August or September and
decline into the winter. This suggests that the birds are not just
arriving on a winter range but are passing through. Further evidence
to support this movement comes in the form of banding returns. A
bird banded near Richmond was found nearly 170 km to the southeast
at Darrington, Washington (Jewett et al. 1953; Table 6). Another
bird, banded near Port Hardy, was found near Richmond (Table 6).
The situation at Victoria differs in
that when the influx of "migrants" reaches the shoreline at the
southern tip of Vancouver Island, it is confronted by a substantial
barrier in the form of a sea crossing of at least 11 km to reach
the San Juan Islands or 24 km to the Olympic Peninsula. Observation
and banding studies undertaken near Victoria during the winter of
1992 revealed that the jays collect in flocks in shoreline trees,
the flocks at times consisting of over 90 birds. These birds indicate
an urge to continue southward; however, after testing the distance
several times, they appear to give up and disperse onto winter areas
in and around Victoria. This dispersal of the "migrating" groups
may be easily misinterpreted as a departure on continued southward
migration. One flock of 12 was seen to embark on the crossing of
Haro Strait to San Juan Island; however, there is no evidence that
this is a characteristic event (Stewart and Shepard 1994). Banding
confirmed that most of the birds pass the winter near Victoria as
relatively sedentary groups.
The autumn populations of the Steller's
Jay differ significantly from year to year, and from time to time
the movement to lowland areas of Vancouver Island results in large
concentrations (Munro and Cowan 1947). For example, unusually large
numbers of jays occurred in the vicinity of Victoria in the autumns
of the following years: 1913 (J.A. Munro in Bent 1946),1919 (Anderson
1920),1922-23 (J.A. Munro in Bent 1946), 1940 (Pearse 1946), 1957
(Schultz 1958a), and at least 5 times over the period 1958 to 1993.
These latter irruptions are noticeable on the Victoria Christmas
Bird Counts.
Similar, although less dramatic, concentrations
can be seen on other Christmas Bird Counts in the province.
In winter, the Steller's Jay is more
abundant in lowland habitats, both natural and human-influenced,
than during other seasons. For example, Cannings et al. (1987) note
a distinct movement in winter to riparian thickets and residential
areas in the Okanagan valley, and the same is true in the vicinity
of Victoria, Vancouver, and the many other towns on eastern Vancouver
Island and in the Fraser Lowland. They rarely stay to nest. On the
coast, these jays disperse to breeding areas in March or April,
and in the interior, in April or May.
The Steller's Jay occurs every month
of the year in all but 3 ecoprovinces. In the Sub-Boreal Interior
there are no March records, in the Boreal Plains records are lacking
for May and July, and in the Northern Boreal Mountains the few records
are between 13 June and 8 September. |
Breeding
The
known nesting distribution of the Steller's Jay is concentrated
along the southern regions of the province from the International
Boundary north to about latitude 51 °30'N, although it likely
breeds throughout most of its range in the province. Its breeding
status in the Peace Lowland of the Boreal Plains and in the Northern
Boreal Mountains remains uncertain. There is only 1 nesting record
north of the latitude of Rogers Pass, although we have records of
fledged young from Barney Creek and Pine Pass in the Sub-Boreal
Interior, and from Langara Island and Graham Island on the Queen
Charlotte Islands.
The Steller's Jay reaches its highest
numbers in summer in the Georgia Depression and on Western Vancouver
Island. An analysis of Breeding Bird Surveys for the period 1968
through 1993 shows that the number of birds on coastal routes has
increased at an average annual rate of 3%. Surveys for interior
routes contain insufficient data for analysis. North American populations
appear stable (Robbins et al. 1986).
The Steller's Jay nests from near sea
level to 1,830 m elevation. Most nests (66%; n = 70) were found
in human influenced coniferous, mixed forest, or woodland habitat.
One-third of the nests were found in undisturbed forest. This sample
is probably heavily biased by the greater likelihood of nests close
to human habitation being discovered, and does not reflect the normal
distribution of nesting habitat. Forest types included Interior
Douglas-fir, Interior Western Hemlock/Redcedar, and Subalpine Fir/
White Spruce. Specific nest habitat included backyard, farm, and
recreational area environments (88%; n = 48), and both young and
mature forest, including forest edges (12%). In the Okanagan and
Kootenay valleys, most nests were found in treed gardens.
The Steller's Jay has been recorded breeding
on the coast from 1 April (calculated) to 28 June; in the interior,
it has been recorded from 3 April (calculated) to 6 July. |
| Nests: 
Most nests (85%; 71 = 41) were situated
in coniferous trees. These were usually small second-growth trees,
almost equally divided between Douglas-fir, western hemlock, western
redcedar, and spruce. Other categories of nests sites included deciduous
vegetation (9%), mostly garden shrubs, and buildings (6%; Grant
1949). The majority of nests were set on horizontal branches close
to the trunk and near the top of the tree. When nesting near human
habitation, the jays frequently placed the nest within a few feet
of a window, verandah, or well-used pathway, suggesting that some
birds can tolerate a fair amount of disturbance.
The heights of 65 nests ranged from ground
level to 9 m, with 68% between 2 and 5 m.
The base of the nests consisted of coarse
twigs (69%; n = 55) or branches (28%), with dry grass present in
35% of nests, and leaves, moss, string, plant stems, and other materials
in lower frequency. Several nests had a mud cup (24%); the most
frequent lining material of the deep cup consisted of fine rootlets,
sometimes with fine grass, moss, and paper.
Eggs:
Dates
for 35 clutches ranged from 4 April to 3 July, with 60% recorded
between 19 April and 24 May. Calculated dates indicate that nests
can have eggs as early as 1 April. Sizes of 28 clutches ranged from
3 to 5 eggs (3E-1, 4E-26, 5E-1), with 93% having 4 eggs. The incubation
period is about 16 days (Ehrlich et al. 1988).
Nest
Success:
Of 8 nests found with eggs and followed
to a known fate, 3 produced at least 1 fledgling. This low success
rate may well be an artifact of the proximity of many nests to human
disturbance.
Young: Dates for 40 broods ranged from
13 April to 6 July, with 51% recorded between 14 May and 9 June.
Sizes of 26 broods ranged from 2 to 5 young (2Y-6, 3Y-6, 4Y-12,
5Y-2), with 69% having 3 or 4 young. The nestling period is about
20 days (Goodwin 1976).
Brown-headed Cowbird Parasitism: Cowbird
parasitism was not found in British Columbia in 66 nests recorded
with eggs or young. There are no instances of parasitism reported
for North America (Friedmann et al. 1977; Friedmann and Kiff 1985). |
Remarks
The American Ornithologists' Union (1957)
recognizes 6 subspecies of the Steller's Jay in North America, 3
of which occur in British Columbia. C. s. stelleri is generally
resident on the coast from southeast Alaska south to Oregon; C.
s. annectens is resident in the interior east of the Coast Mountains
(Brooks 1927); C. s. carlottae is an endemic subspecies,
resident on the Queen Charlotte Islands. C.s. carlottae has
the most restricted distribution of the 6 subspecies, and probably
a small total population. For details of the identifying features
of the subspecies, see Stevenson (1934).
Infrequent hybridization between the
Steller's Jay and the Blue Jay is thought by some authors to indicate
that the two constitute a superspecies (American Ornithologists'
Union 1983).
In 1987 the Steller's Jay was declared
the official provincial bird of British Columbia. Over 80,000 residents
participated in a vote to select a provincial bird to commemorate
the centennial of wildlife conservation in Canada. |
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