Birds of Prey
Gyrfalcon
Gyrfalcons
(Falco rusticolus)
are the world’s largest falcon (50-63 cm tall).
The colour of their plumage varies from dark grey throughout the
mountains and southern tundra of the NWT to light grey or white in the
east and on the Arctic islands.
 The
gyrfalcon does not build a nest. Instead,
two to four eggs are laid and incubated by the
female on a narrow cliff ledge or, more usually, in the stick nest of
other species such as ravens and golden eagles. Gyrfalcons nest in April
in the Mackenzie Mountains and in May over the rest of their range. The
same nesting ledge is frequently used in successive years, or a breeding
pair may alternate among several nesting ledges within a small area.
Ptarmigan,
the primary prey, are flushed into the open as the gyrfalcon flies low and fast
over the tundra. At times,
lemmings, ground squirrels, hares and other birds may also be consumed.
Gyrfalcons nesting near the Arctic coast feed primarily upon seabirds
which are attacked in the air.
The
eyasses fledge about 47 days after hatching.
During fall and winter, the immatures and some adults wander south into
the boreal forest in search of ptarmigan concentrations.
Other adult gyrfalcons remain close to their nesting area, feeding on
overwintering ptarmigan flocks or hares.
It appears that the number of gyrfalcons and nesting success vary in response to
the amount of prey available.
The
habits of the gyrfalcon are not well known, and since 1982 have been under study
by the NWT Department of Environment and Natural Resources.
New knowledge of the biology of gyrfalcons is essential in caring for
this unique northern raptor.
Gyrfalcons
have always been highly prized by falconers.
During the middle ages when falconry was a common practice, no one but a
king or prince was allowed to own and fly a gyrfalcon.
Today this falcon still retains its high status in the world of falconry.
|
