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Vancouver
Island is home to an abundance of wildlife and their related ecosystems.
Some of these are now threatened due to urban advancement and
habitat degradation. Some
of the species at risk are as follows:
MARBLED
MURRELET (Brachyramphus marmoratus)
The
marbled murrelet, a small seabird which nests in the coastal, old-growth
forests of the Pacific Northwest, is listed as a threatened species
under the Endangered Species Act. In North America, the birds' range
stretches along the Pacific coast from the Bering Sea to central
California with the largest populations occurring in southeastern Alaska
and northern British Columbia.
The
murrelet's dependence on old-growth nesting habitat and use of coastal
marine feeding areas have brought it into frequent conflict with human
economic interests, especially in the southern portion of its range
where small, geographically concentrated populations are especially
vulnerable to extirpation. However, both natural and human-related
factors may be contributing to the species' decline; potential causes
include the loss of suitable nesting habitat, accidental death in
gill-nets, oil pollution, increases in predator populations, and
declines in food supplies due to recent El Nino events.
The
Marbled Murrelet could easily lay claim to the title “most mysterious
bird on the Pacific coast of Canada.” It nests on the mainland in
almost total obscurity, although people who fish and boat along the
British Columbia coast during spring and summer (when the birds are
nesting) often see Marbled Murrelets out on the water. Amazingly, in the
200 years that the species has been known to science, observers in
British Columbia have seen only one occupied nest, in 1990. The story is
the same over the whole of the murrelet’s North Pacific range (see
map). To date, there are just over a dozen recorded sightings of
occupied nests from Canada, Japan, Russia, and the United States.
PURPLE
MARTINS
(Progne subis)
The
Purple Martin is a conspicuous bird in many populated areas of North
America during spring and summer. Averaging
17 to 20 cm in length, it is Canada’s largest swallow. The Purple
Martin resembles other swallows in having a slender body, long wings,
and a wide beak. The tail is forked but not deeply as in some other
swallows. Male martins, with their dark plumage, often appear to be
black, but on bright sunny days their shiny blue-black coloration is
clearly visible. Female martins are lighter in colour, with a pale grey
throat and belly. By the
time they have left the nest, young martins of both sexes resemble adult
females. Young males only become dark at their second breeding season.
The Purple Martin
breeds throughout much of southern Canada, including Nova Scotia, the
southern portions of New Brunswick, Quebec, Ontario, and Manitoba;
southern and central Saskatchewan; and north-central Alberta. In British
Columbia, martins are found in the Peace River region, southern
Vancouver Island, and the extreme southwestern mainland.
Martins are much less common in western Canada than in the
eastern provinces.
Martins
arrive in Canada in early spring, usually in early April in Quebec and
Ontario and from late April to early May in other areas.
Martins have been banded, or tracked by placing a numbered aluminum band
around the leg, for many years. Recoveries of banded martins have
provided extensive information about the movement of these long-distance
migrants. Of the adult birds banded and sighted again, most had returned
to the breeding colonies where they were banded or to one near by.
Banded nestlings have also typically returned to their home colonies to
breed, although a few young bred hundreds of kilometers from their
birthplace. Banding has also provided information on the lifespan of
martins. Most martins live to four or five years. The oldest martin on
record is an eight-year-old recaptured at its breeding colony.
The
ability of martins to find their colony is remarkable. In one
experiment, adults that were transported several hundred kilometers from
their nesting colonies returned in a matter of days.
How
to encourage these species on your property
SHARP TAILED SNAKE
(Contia tenuis)
This
is a small, slender snake 20-45 cm from snout to vent.
It is coppery or reddish on the back, with darker sides. The
belly is whitish with a half-moon shaped crossbar on each scale. The
tail is tipped with a small spine. A variety of habitats are used by
this snake ranging from Garry oak grasslands to forest. It is usually
found near water or in clearings near forests. When the soil is damp it
spends much of time under rocks or logs, but when the soil dries out it
will retreat underground.
Sharp-tailed
snakes are rare, and seem to occur in widely scattered populations. They
are most active on the surface in early spring and again in late fall.
They eat primarily small slugs, and have special long teeth for biting
them. It is a Red-listed
species in BC and confirmed occurrences of sharp-railed snakes have been
recorded at only seven locations in BC, all on southern Vancouver Island
and the Gulf Islands. These
snakes are very secretive and hard to find, making population sized
difficult to estimate.
In BC, sharp-tailed
snakes are at the northern extremity of their range, and it in unlikely
they were ever abundant.
Conservation efforts
have recommended private landowners avoid using pesticides and chemical
slug-bait, and try to maintain natural area with protective cover in
your yard.
COMMON
RINGLET (Coenonympha california insulana)
The
common ringlet’s wing colour ranges from dark orange-brown to pale
cream with the underside of the forewing usually having a small eyespot
near its tip. The underside of hindwing is gray-green with a wavy white
median line and has a total wing span
of 1 1/3 - 1 1/2 inches (3.4 - 3.8 cm) and they have a
characteristic bouncing flight pattern.
This
butterfly is extremely variable geographically, with at least 4
subspecies. They may be found in suitable habitats in the Pacific
Northwest from southwestern BC to Oregon, including the San Juan Islands
and Garry oak ecosystems. In
the 1950’s this subspecies was one of the most abundant butterflies on
Vancouver Island, but it is now rare and has been Red-listed in BC.
Butterfly
populations are very closely linked to the availability of larval and
adult foodplants. The
common ringlet larva require green native grasses as food and may also
feed on sedges. Suitable
habitats include open areas with short grass, in locations that have
sufficient moisture for the vegetation to stay green throughout the dry
summer without being subject to flooding in winter.
Protection of suitable
habitat and food sources may help reduce the decline of this species. Removal of invasive shrubs such as Scotch broom and the
reintroduction of native grasses will help this butterfly as well as
many other native species that depend on similar habitats.
LEWIS’S
WOODPECKER (Melanerpes lewis)
Adult
Lewis's Woodpeckers have a medium sized head, short neck, and large
body. The bill and feet are dusky blue-gray. The back of this species is
black, glossed with green, and the belly is rose red. There is a deep
red band which runs across the forehead and throat, extending behind and
below the eye. The throat and wings are black with a band of dull white
over the hind neck extending forward and around the breast. The adult
female resembles the male, although she is slightly duller in color with
less red on the front of the head. The wings are long, spanning to 21
inches. The tail is of medium length and very strong. It has ten
feathers that are pointed and stiff. The outside feathers are shorter
than the center ones.
This woodpecker’s
diet varies with the seasonal abundance of food items; primarily
free-living (not wood-boring) insects older than larval stage,
principally ants, bees, and wasps, beetles, and grasshoppers; acorns or
other nuts, and fruit.
Vocalizations:
Drum:
Drum is short, weak, and at medium speed followed by several individual
taps.
Calls:
A series of short, harsh chr
notes. The "contact call" is a weak, sneezy teef or kitsif; also a
high, squeaky, descending rik rik
rik. Dry, rattling
chase series reminiscent of European Starling.
It’s three principal
habitats are open ponderosa pine forest, open riparian woodland
dominated by cottonwood, and logged or burned pine forest; however
breeding birds are also found in oak woodland, nut and fruit orchards,
pinyon pine-juniper woodland, a variety of pine and fir forests, and
agricultural areas including farm and ranchland. Important aspects of
breeding habitat include an open canopy, a brushy understory offering
ground cover and abundant insects, dead or downed woody material,
available perches, and abundant insects.
The
Lewis’ Woodpecker is of high conservation importance, because of its
relatively small and patchy distribution, low overall density, and
association with mature montane and riparian forests. This species is
poorly monitored in many parts of its range, but exhibits a significant
long-term decline overall. Populations may have declined by as much as
50 % since 1966. Associations with various forest types, sensitivity to
fragmentation and silvicultural practices are poorly known and will be
important to understand for sustaining healthy populations.
The
Georgia Depression population of Lewis’s woodpeckers is red-listed in
BC, presumed extirpated. Current occurrences of this species here are
restricted to occasional appearances of single birds on southeastern
Vancouver Island and in the lower Fraser River Valley.
This extirpation occurred at the same time as range-wide
population declines. Habitat
loss and degradation are thought to be primary factors, with urban
development, fire suppression, and removal of dead and dying trees being
the greatest sources of reduced habitat sustainability.
Patches of suitable
habitat still exists on Vancouver Island, and general measures to
restore and protect these area may eventually permit natural or human
assisted re-introduction. Nesting
habitat will be maintained and increased by the retention of dead and
declining tress and ‘planting’ of artificial snags.
Such habitat enhancement would be of greatest benefit in concert
with management of European starling populations.
Steps should also be taken to control local pesticide use that
negatively affects population of flying insects.
PROPERTIUS
DUSKYWING (Erynnis
propertius)
The
Duskywing’s Upperside is predominantly brown; forewings with gray
overscaling and distinct dark markings. Clear spots are small in the
male, large in the female. The underside of the hindwing has
well-defined spots below the apex. Wing span: 1 3/8 - 1 3/4 inches (3.5
- 4.5 cm).
Their
preferred habitat is open oak woodlands, forest openings and edges,
meadows and fields near oaks from sea level to middle elevations. Does not occur in deserts or hot central valleys.
They range in southern British Columbia south along the Pacific
Slope to Baja California Norte.
Duskywing’s
generally have only one generation per year, although there may
occasionally be a second brood. Adults
are most commonly seen on the wing in April and May.
Propertius duskywings
are red listed in BC and are disappearing along with Garry oak habitats,
especially in rapidly urbanizing area.
These duskywings disappear from urban area even where Garry oak
trees are left standing, perhaps because of pesticide use and in part
because of the “cleaning up” of leaf litter containing overwintering
pupae.
The best suggested way
to preserve this species is to protect large area of Garry oak woodland
and keep them clear of invasive species such as Scotch broom and
non-native grasses. Leaf
litter should be left around the base of Garry oak trees for
overwintering larvae, and surrounding grasslands left in a natural
state. Avoid the use of
pesticides.
STREAKED
HORNED LARK
(Eremophila alpestris
strigata)
The
Streaked Horned Lark is a small, ground-dwelling songbird with
conspicuous feather tufts, or "horns," on its head. Its back
is heavily streaked with black, contrasting sharply with its deeply
ruddy brown nape and yellow underparts. The male is distinctively marked with a dark facial mask and
breastband that contrasts with the pale face and throat.
The historical range
of streaked horned larks was confined to the coastal plain of
southwestern BC, Washington and Oregon.
Populations in BC were likely never numerous, and this subspecies
is virtually extirpated from Vancouver Island (one territorial male was
seen during the 2002 breeding season).
Breeding occurs from
early April to August, and nests are built in a hollow in the ground,
often beside a clump of dirt or tuft of grass.
These larks are most often found in are areas with bare ground,
including spits, estuaries, sand dunes and Garry oak meadows, as well as
some modified areas such as pastures, playing fields, airports and
roadsides.
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