. Birds of America;. Birds -- North America. BIRD MIGRATION ix Nor are they content with journeying to northern South America, but many cross the Equator and pass on to the pampas of Argentina and a few even to Patagonia. Among these long-distance migrants are some of our commonest birds; the Scarlet Tanager migrates from Canada to Peru; the Bobolinks that nest in New England probably winter in Brazil, as do Purple Martins, Cliff Sparrows, Barn Sparrows, Nighthawks, and some Thrushes, which are their companions both summer and winter. The Black-poll Warblers that nest in Alaska winter in north
. Birds of America;. Birds -- North America. BIRD MIGRATION ix Nor are they content with journeying to northern South America, but many cross the Equator and pass on to the pampas of Argentina and a few even to Patagonia. Among these long-distance migrants are some of our commonest birds; the Scarlet Tanager migrates from Canada to Peru; the Bobolinks that nest in New England probably winter in Brazil, as do Purple Martins, Cliff Sparrows, Barn Sparrows, Nighthawks, and some Thrushes, which are their companions both summer and winter. The Black-poll Warblers that nest in Alaska winter in northern South America, at least 5,000 miles from the summer home. The land bird with the longest migration route is probably the Nighthawk, which occurs north to Yukon and south 7,000 miles away, to Argentina. But even these distances are surpassed by some of the water birds, and notably by some of the shorebirds, which as a group have the longest migration routes of any birds. Nine- teen species of shorebirds breed north of the Arctic Circle, every one of which visits South America in winter, six of them penetrating to Patagonia, a migration route more than 8,000 miles in length. The world's migration champion, however, is the Arctic Tern. The shape of the land areas in the northern half of the Western Hemisphere and the nature of the surface has tended to great variations in migratory movements. If the whole area from Brazil to Canada were a plain with the general characteristics of the middle section of the Mississippi Valley, the study of bird migration would lose much of its fascination. There would be a simple rhythmical swinging of the migration pendulum back and forth, spring and fall. But much of the earth's surface between Brazil and Canada is occupied by the Gulf of Mexico, the Caribbean Sea, and parts of the Atlantic Ocean, all devoid of. Most migrants use n traverse the mo along route No. l^jurtL-sy of U. S. Uept. of Agriculture PRINCIPAL MIGRATION ROUTES OF NORTH AMER
Size: 1733px × 1441px
Photo credit: © Library Book Collection / Alamy / Afripics
License: Licensed
Model Released: No
Keywords: ., bookauthorpearsont, bookcentury1900, bookdecade1920, bookyear1923
