This week’s Bird of the Week, compliments of the Weminuche Audubon Society and Audubon Rockies, is the northern shrike.
This is another bird of the far north that travels to regions like ours to spend the winter. In summer it breeds throughout Alaska and the far northern reaches of Canada, but migrates to western Canada and the northern United States for winter. We are at the southern edge of its winter range.
During migration and in winter, northern shrikes are found in partially open habitats with brushy cover. In all seasons they avoid completely open and densely forested areas.
Northern shrikes are colored gray, have a thick neck, rounded head and thick, hooked bill. They have black feathers in the wings and tail and a black mask that narrows where it meets the bill. They are very similar in appearance to the loggerhead shrike, whose mask is thicker and usually extends over the bill, and whose white undersides lack the barring of the northern’s.
This medium-sized songbird is strictly a carnivore and a ferocious hunter. In summer it primarily feeds on insects, with the addition of some small birds and mammals. In winter when insects are scarce, birds and rodents become the main sources of food. Small birds are most commonly taken, but the shrike will also hunt birds larger than itself like robins, jays and doves.
Shrikes lack the talons of larger birds of prey and instead use strong feet to hold their captures down while delivering a killing bite that severs the spinal cord. They are known to kill more prey than they can eat at once, but save the excess for later by hanging it on thorns, barbed wire or notches in trees. This hanging of carcasses from hooks like meat in cold storage has earned them the nickname of “butcher birds.”
Even in winter northern shrikes are territorial and aggressive against other bird species. Their hunting territory may be more than 360 acres in size. They are most easily spotted when they occupy a prominent perch to scan for prey. Take a second look at that bird sitting on the wire and you might just find this one.
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