I am Headmaster Dark Cloud.
Now everyone please
take a seat behind this ridge here.
We are going to be looking
into the trees and on the ground to
see if we can spot any Snowy Owls.
Now please be alert!
~SNOWY OWL~
Snowy Owl (Nyctea scandiaca)
Some other names for the Snowy Owl are
Arctic Owl, Great White Owl, Ghost Owl, Ermine Owl,
Tundra Ghost, Ookpik, Scandinavian Nightbird, White Terror of
the North, and Highland Tundra Owl. It is
the official bird of Quebec.
Description: The Snowy Owl is a large, diurnal white
Owl that has a rounded head, yellow eyes
and black bill. The feet are heavily feathered.
A distinctive white Owl, their overall plumage is
variably barred or speckled with thin, black, horizontal
bars or spots. Females and juveniles are more
heavily marked than males - adult males may be
almost pure white, although they have up to
three tail bands. Adult females are distinctly barred
throughout, and have from four to six tail
bands. Immatures are very heavily barred throughout, and
dark spotting may codominate or dominate the overall
plumage. Intensity of dark spotting varies with the
sex of the immatures, females being the darkest.
Juveniles are uniformly brown with scattered white tips
of down.
Snowy Owls have a direct, strong, and steady flight
with deliberate, powerful downstrokes and quick upstrokes.
They make short flights, close to the ground,
from perch to perch, and usually perches on the
ground or a low post. During hot weather,
they can thermoregulate by panting and spreading their
wings.
Size:
average female average male
Length: 51-68½cm (20-27 inches) 66cm (26 inches) 59cm (23 inches)
Wingspan: 137-164cm (54-65 inches)
Weight: 1134-2000g (40-70oz) 1707g (60oz) 1612g (57oz)
Voice:
The Snowy Owl is virtually silent during nonbreeding seasons.
During the breeding season males have a loud,
booming "hoo, hoo" given as a territorial advertisement
or mating call.
Females rarely hoot. Its attack call is a
guttural "krufff-guh-guh-guk". When excited it
may emit a loud "hooo-uh, hooo-uh,
hooo-uh, wuh-wuh-wuh". Other sounds are dog-like
barks, rattling cackles, shrieks, hissing, and bill-snapping.
Nestlings "cheep" up to 2 weeks of age, then hiss and squeal.
Hunting & Food:
Most hunting is done in the "sit and wait"
style, swivelling the head as much as 270
degrees scanning for prey. These Owls are highly
diurnal, although they may hunt at night as
well. Prey are captured on the ground, in
the air, or snatched off the surface of
water bodies.
When taking snowshoe hares, a Snowy Owl will
sink its talons into the back and backflap
until the hare is exhausted. The Owl will
then breaks its neck with its beak. Snowy
Owls will often raid traplines for trapped animals
and bait, and will learn to follow traplines
regularly. They also snatch fish with their talons.
Small prey up to small hares are swallowed
whole, while larger prey are carried away and
torn into large chunks. Small young are fed
boneless and furless pieces. Large prey are carried
of in the Owl's talons, with prey like
lemmings being carried in the beak.
Snowy Owls are mainly dependent on lemmings and
voles throughout most of their Arctic and wintering
range. When these prey are scarce they are
an opportunistic feeder and will take a wide
range of small mammals and birds. Some mammal
prey include mice, hares, muskrats, marmots, squirrels,
rabbits, prairie dogs, rats, moles, and entrapped furbearers.
Birds include ptarmigan, ducks, geese, shorebirds, Ring-necked
Pheasants, grouse, American coots, grebes, gulls, songbirds, and
Short-eared Owls. Snowy Owls will also take
fish and carrion.
Some nesting Owls switch from lemmings and voles
to young ptarmigan when they become available. Snowy
Owls do not hunt near their nests, so
other birds, such as Snow Geese, often nest
nearby to take advantage of the Owls driving off
predators such as foxes.
Snowy Owls produce large, rough-looking cylindrical pellets
with numerous bones, feathers, and fur showing. They
are usually expelled at traditional roosting sites and
large numbers of pellets can be found in
one spot. When large prey are eaten in
small pieces with little roughage, pellets will not
be produced.
Breeding:
Courtship behaviour can begin in midwinter through to
March and April, well away from breeding areas.
Males will fly in undulating, moth-like flight
when females are visible. On the ground males
will bow, fluff feathers, and strut around with
wings spread and dragging on the ground. Males
kill and display prey in caches to impress
females, often feeding the female. The Snowy Owl
nests almost exclusively on the ground, where the
female makes a shallow scrape with her talons
on top of an elevated rise, mound, or
boulder. Abandoned eagle nests and gravel bars are
used occasionally. Nests may be lined with scraps
of vegetation and Owl feathers. Nest sites must
be near good hunting areas, be snow-free,
and command a view of surroundings. There is
little breeding site-faithfulness between years or mates
in some areas, but in other areas, a
pair of Owls may nest in the same
spot for several years. Territories around nests range
from 1½ to 6½ square kilometres (0.6 to 2½ square miles),
and overlap with other pairs.
Breeding occurs in May, Clutch and brood sizes
are heavily dependent on food supply. Snowy
Owls may not nest at all during years
of low lemming numbers. Clutch sizes normally range
from 5 to 8 white eggs but may
be as many as 14 eggs during high
lemming years. They are laid at approximately 2
day intervals. The female incubates while the male
brings her food and guards the nest. Eggs
hatch in 32-34 days at two day
intervals, leading to large age differences in nests
with large clutch sizes. Young are covered in
white down. Young begin to leave the nest
after about 25 days, well before they can
fly. They are fledged at 50 to 60
days. Both parents feed and tend the young,
and are fiercely protective and may attack intruders
up to 1 kilometre (0.6 miles) from the
nest! Nestling Owls require about 2 lemmings/day
and a family of Snowy Owls may eat
as many as 1,500 lemmings before the young
disperse. Snowy Owls are single brooded and likely
do not lay replacement clutches if their first
clutch is lost. Almost 100% nesting success can
be achieved during good vole years.
Numbers fluctuate wildly, usually in concert with lemming
and vole numbers. For Example, Banks Island may
have 15,000 to 20,000 Snowy Owls during good
lemming years and only 2,000 during low lemming
years with densities ranging from 1 Owl per
2.6 square kilometre (1 Owl per square mile)
in good lemming years to 1 Owl per 26
square kilometres (1 Owl per 10 square miles)
in low lemming years.
Mortality:
Snowy Owls can live at least 9½ years
in the wild and 35 years in captivity.
Natural enemies are few - Arctic foxes and wolves
prey apon them on their tundra breeding grounds,
while skuas and jaegers may take eggs or chicks.
Habitat:
The Snowy Owl is a bird of Arctic
tundra or open grasslands and fields. They rarely
venture into forested areas. During southward movements they
appear along lakeshores, marine coastlines, marshes, and even
roost on buildings in cities and towns. In
the Arctic, they normally roost on pingaluks (rises
in the tundra) and breed from low valley
floors up to mountain slopes and plateaus over
1,000 meters (3,000 feet) in elevation. When wintering
in the Arctic, they frequent wind-swept tundra
with little snow or ice accumulation. At more
southern latitudes they typically frequents agricultural areas.
Distribution:
Circumpolar - Arctic regions of the old and new worlds.
North America - Snowy Owls breed in the western
Aleutian Islands, and from northern Alaska, northern Yukon,
and Prince Patrick and northern Ellesmere islands south
to coastal western Alaska, northern Mackenzie, southern Keewatin,
extreme northeastern Manitoba, Southampton and Belcher islands, northern
Quebec and northern Labrador. The Snowy Owl is highly nomadic.
During periods of lemming and vole population crashes
in the Arctic, or excessive cold and snow
in winter, mass movements of Snowy Owls occur
into southern Canada and northern United States. These
invasions occur every 3 to 5 years, but
are highly irregular. Adult females stay furthest north
while immature males move furthest south during these
incursions. In some years small numbers may reach
as far south as central California, southern Nevada,
Utah, Colorado, Oklahoma, central and southeastern Texas, the
Gulf States and Georgia.
~PORT KEY!~
