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Shrikes

species birds occur north

Shrikes are 72 species of perching birds that make up the family Laniidae, in the order Passeriformes. The diversity of shrikes is greatest in Africa, with species also occurring in Europe, Asia, and Southeast Asia as far south as New Guinea. Two species occur in North America. Shrikes occur in a wide range of habitats, including forest edges, open forest, savanna, grassland, and some types of shrubby cultivated land.

A Northern shrike perched on a branch. Photograph by Ron Austing. The National Audubon Society Collection/Photo Researchers, Inc. Reproduced by permission.

Shrikes are medium-sized birds with body lengths ranging from 6-14 in (15-36 cm). They have a relatively large head, and a stout beak, with a notch on each side and a pronounced hook at the tip of the upper mandible. The wings are pointed, the legs are strong, and the feet have sharp claws. Most species are gray or brown on the back and wings, with black markings, and whiter below. Some species, however, can have a rather colorful plumage.

Shrikes are aggressive predators. They typically hunt from a perch that gives them a wide vantage of their surroundings. When prey is detected, the shrike swoops at it, and kills it with a sharp blow with the beak. Shrikes feed on large insects, reptiles, small mammals, and small birds. Shrikes carry their prey in their beak, and many species commonly impale their food on a thorn or barbed wire. This is done either to store for later consumption, or to hold the body still while it is torn apart during eating. Shrikes are sometimes called butcher-birds, because of their habit of lardering (or storing) their meat.

Shrikes build a bulky, cup-shaped nest in a shrub or tree. They lay two to six eggs, which are incubated by the female. The male assists with the rearing of the young birds.

The northern or great grey shrike (Lanius excubitor) ranges from Canada to northern Mexico, and is also widespread in Europe, Asia, and North Africa. The loggerhead shrike (L. ludovicianus) is a smaller species with a more southern distribution, and it only breeds in North America. Populations of both of these species, but particularly those of the loggerhead shrike, appear to have declined substantially. The causes of the declines of these predatory birds are not well known, but are thought to be largely due to pesticides in their food web, and habitat changes, especially those associated with the intensification of agriculture.

See also Vireos.

KEY TERMS

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Grassland

A type of rangeland that is usually free of shrubs and trees. Grasslands most commonly occur on flat, inland areas at lower elevations.

Savanna

—A treeless plain of high grasses found in tropical climates.

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