Dippers occur on five continents: the Americas, Eurasia, and marginally, in Africa. Because of their habitat requirements they are largely confined to mountainous regions with rushing streams. Hence they are absent from large lowland areas of all the continents on which they breed. In North America they occur throughout the western states and provinces, from the Arctic Circle in Alaska, south through Central America to Panama, but are, curiously, absent from the eastern two-thirds of the continent, including areas of apparently suitable habitat in eastern Canada, New England, and the Appalachians. In South America they occur exclusively in the Andes and adjacent mountains, from Venezuela and Colombia south to northern Argentina. In Europe, they occur from Scandinavia and the British Isles across to Greece, Turkey, Syria, and the Caucasus; they are also found in suitable habitat in North Africa. In Asia, they occur in isolated areas of the Ural mountains, central Asia from Afghanistan to eastern Siberia and Japan, south to Burma and north-western

Mexican (or American) dipper (Cinclus mexicanus) with food for its chicks. (Photo by Jeff Foott. Bruce Coleman Inc. Reproduced by permission.)

Thailand. Dippers have not succeeded in colonizing suitable habitat in Africa south of the Sahara, southern India, or Australasia; in these areas their ecological niche is exploited by birds of several families, none of which, however, has evolved the unique structural and behavioral characteristics of dippers.

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