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 Northern
Shrike
Shrikes are the only
songbirds to consistently prey on vertebrate animals.
They feed on small mammals and birds for much of year and
often store uneaten prey by impaling it on thorns. This
habit has earned them the nickname "butcher
birds."
The Northern Shrike and the similar Loggerhead Shrike are
the only two members of the shrike family to be found in
North America. Whereas the Loggerhead Shrike nests
throughout the West and Southeast, the Northern Shrike
nests in the far North. It breeds from Alaska across
northern Canada through the Northwest Territories to
northern Quebec and central Labrador, as far north as the
tree line. The edges of coniferous forests and open
willow brush country are preferred habitat. The Northern
Shrike is also found in many of the northern regions of
Eurasia.
Northern Shrike
Range Map
Normally a solitary hunter, it perches atop trees and
scans for prey. When prey is sighted, the bird drops from
its perch and flies low over the ground, in slightly
undulating flight to the attack. It knocks flying victims
to the ground with a blow from its bill or seizes them
with its feet. Once on the ground, it kills with a series
of bites. Like the bills of falcons, shrikes' bills are
hooked, with a toothlike structure on the upper mandible
and a corresponding notch on the lower bill. Their
eyesight is comparable to that of diurnal raptors. Unlike
raptors, however, the shrike lacks the powerful talons
that hawks use to dispatch their prey. Another hunting
strategy is to move through the branches of trees trying
to flush birds, which are then pursued. Birds as large as
Blue Jays and Mourning Doves may be taken, as well as
many smaller birds such as chickadees, Snow Buntings,
crossbills, sparrows, and redpolls. Mammalian prey
includes lemmings, voles, and mice. Insects such as
grasshoppers, crickets, flies, beetles, wasps, and
caterpillars are also eaten and may make up to
one-quarter of the shrike's diet in season. Prey is often
carried to a thorny tree or shrub to be impaled. If it's
hungry, the shrike consumes its prey at once, but
sometimes food is left impaled for short-term storage.
Northern Shrikes sing a medley of short liquid trills and
whistles and harsh notes and often mimic the calls and
songs of other birds such as Blue Jays, Gray Catbirds,
American Robins, and Song Sparrows. The call is a harsh shek-shek
or a grating jaaeg.
Northern Shrikes are migratory, wintering from the
southern parts of their breeding range to as far south as
northern California, Arizona, and New Mexico through the
northern Great Plains and east to Pennsylvania and New
Jersey. Numbers in winter vary considerably and may be
related to the cycles of small mammals. Christmas Count
data from 1900 to 1935 show a distinct cycle of a peak
"invasion winter" every 4.2 years, but after
1935, the cycle disintegrates and irruptions have since
occurred during different years in the East and West.
Description: The Northern Shrike is a
robin-sized bird that is approximately 9.00 to 10.75
inches in length. It is gray above and white below, with
a black mask through the eyes and a finely barred breast.
The wings are black with white patches, and the tail is
black with white at the outer feathers. Immatures are
similar to adults, but the mask is faint, and the breast
is more heavily barred.
Northern Shrikes are larger and paler than the similar
Loggerhead Shrike (L. ludovicianus), and they
possess a comparatively longer and more hooked bill. The
rump of the Northern Shrike is white; that of the
Loggerhead Shrike varies from dark gray to whitish. The
barring of the underparts is more distinct and more
extensive than the very faint barring of the Loggerhead.
The Northern Shrike's mask is narrower and does not
extend above the eye nor above the bill; the Loggerhead's
mask is a bit broader and extends in a thin line above
the bill and eye. The Northern Shrike's bill is
bicolored; the Loggerhead Shrike's bill is all black.
The Northern Mockingbird (Mimus polyglottos) is
another bird that might be mistaken for a Northern
Shrike. It is more slender and lacks the distinct mask
and stout hooked beak of the shrikes. When seen in
flight, this mockingbird also shows a white patch near
the end of the wings, but whereas the white patch of the
Shrike forms a band confined to the upper parts of the
primary feathers, the Mockingbird has a double patch
positioned partly on the primary feathers and partly on
the coverts at the "wrist" of the wing.
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