Bird Lore: Northern Shrike

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A solitary and wary hunter, the Northern Shrike usually visits Edmonds in October, when at least one in southbound migration will make an appearance around the Edmonds Marsh. It is an uncommon winter resident throughout Washington and other northern states. The second photo shows this October’s visitor on a foggy afternoon.

Diet includes large insects, rodents, and small birds. It eats many small songbirds in winter and early spring. It also targets voles and other small rodents, as well as many large insects when available. It forages by watching from a perch on the edge of an open field. It then darts out in fast, powerful flight when it spots prey. It lacks the talons of a falcon or hawk so it uses its heavy hooked bill to kill its prey.

A shrike will kill more prey than it can eat immediately or feed to nestlings. It stores excess prey to eat later. It will sometimes impale dead prey on a thorn or barbed wire for later consumption. This behavior is considered an adaptation for surviving periods of food scarcity. This short You Tube video illustrates how shrikes forage.

The Northern Shrike breeds in the far north. It migrates to its breeding grounds in early spring. It seeks out partly open or scattered spruce woods, willow and alder scrub along streams, or tundra edges. The male sings to defend its nesting territory and to attract a mate. Its complex song includes imitations of other bird species. Both adults build the nest, which is an open cup of twigs, grass, bark strips and moss. It is lined with feathers and animal hair. The nest is so deep that the female is completely out of sight except for the tip of her tail when she is incubating the four to seven eggs.

The young hatch about 15-17 days after the female begins incubation. Both adults feed the nestlings. The young leave the nest about three weeks after hatching. The parents tend the young for another few weeks.

The oldest Northern Shrike of record was a female that was 8 years and 7 months when recaptured and re-released during a Wisconsin banding operation. Collective nouns for a group of shrikes include abattoir and watch.

For conservation purposes, the Northern Shrike is a species of low concern. A rough estimate of its global breeding population is 9 million, with 13 percent spending part of the year in Canada and 15 percent wintering in the U.S. Large areas of breeding habitat in northern Canada and Alaska are protected. Although the Northern Shrike is a U.S.-Canada stewardship species, historically it was not always protected. When the now-invasive House Sparrow was introduced from Europe in the 1870s, Boston hired a warden to shoot Northern Shrikes at the Boston Common in winter to protect the House Sparrows.

The Northern Shrike is usually silent away from its breeding grounds, according to one authoritative reference. Another states that both the male and female will sing throughout the year. When one is seen in Edmonds during southbound migration, it is typically silent. One recordist captured the calls of a male in February in Northern Minnesota: https://www.xeno-canto.org/400776  Its more complex song can be heard here: https://www.xeno-canto.org/348235. If you listen to the recordings at these links, you will notice that the bird is described as a Great Grey Shrike. That is the British common name for this circumpolar hunter.

— By Carol Riddell

Carol Riddell manages the bird education displays, on behalf of Pilchuck Audubon Society and Edmonds Parks & Recreation, at the Olympic Beach Visitor Station.

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