Woodland Birds, Pacific Northwest
The Northern Shrike breeds in the Canadian boreal forest. A predatory songbird, the northern shrike likes to breed in open woodlands, bogs and scrub.
The northern shrike is known for its unique behavior of impaling its prey of small birds, mammals and insects on thorns and barbed wire fences, hence its preference for nesting near areas containing such objects. They are called butcher birds because they hang their prey the same way that a butcher will hang meat.
The majority of Canada’s breeding population migrates southward into southern parts of Canada and all of Vancouver Island and sometimes into the northern United States, but these movements can vary in extent from year to year and probably depend on prey availability. Populations are stable now, but forest regeneration, urbanization, and intensive farming, which now dominate many landscapes once favored by shrikes, will probably cause local declines in some areas.
The northern shrike is a robin sized bird that is pale gray above, white below, with a faint barring on underparts, and a bold black mask ending at bill. They have a black tail with white edges and a strong hooked bill. They can usually be seen perched atop a high tree in the open.
You can find this bird across Northern Canada to southern Canada and all of BC coast, look in open woodlands and brushy swamps in summer; open grasslands with fence posts and scattered trees in winter.
Their nest will have 4 to 6 eggs that are spotted with dark gray and brown. The nest a large mass of twigs, lichens, moss, and feathers and usually hidden in a dense conifer forest.
The northern shrike sits quietly, often in the top of a tree, before swooping down after insects, mice, and small birds. It kills more than it can eat, impaling the prey on a thorn or wedging it in a forked twig. On lean days it feeds from its larder.
Like other northern birds that depend on rodent populations, the northern shrike movements are cyclical, becoming more abundant in southern Canada and Vancouver Island when northern rodent populations are low.
Sometimes they hunt from an open perch, where they sit motionless until prey appears; at other times, they hover in the air, ready to pounce on anything that moves.