MIGRATION AND MASS CHANGE OF WHITE-RUMPED SANDPIPERS IN NORTH AND SOUTH-AMERICA

White-rumped Sandpipers (Calidris fuscicollis) migrate between Canadian Arctic breeding areas and "wintering" areas in Patagonia, one of the longest animal migrations in the Western Hemisphere. Migrant White-rumped Sandpipers employ both long-distance, nonstop, and short-distance multiple-stop flights. Southbound migrants fly over the Atlantic ocean from northeastern North America to South America. They then gradually move southeast along northeastern coasts before turning inland in trans-Amazonian travel requiring about one month. Northward migration routes from Patagonia evidently are similar, but are traversed in a rapid series of long nonstop flights. Staging zones are unknown in nor-them South America during north migration, in the Caribbean basin, or on the Atlantic coastal plain of the U.S. A major staging area is identified in the Great Plains, where birds evidently prepare for a last remaining flight to the Arctic. The migration system of this small sandpiper makes the species vulnerable to loss of strategic migration habitats.