An analysis of band returns of the American White Pelican, 1922 to 1981

摘要

A total of 3,859 band-recovery records of the American White Pelican (Pelecanus erythrorhynchos) banded between 1922 and 1981 at 77 sites in the U.S. and Canada was analyzed using a Geographic Information System (GIS). Returns showed a clear pattern of two major migratory routes, with birds from California, Oregon and Nevada breeding colonies dispersing south to the coasts of the Gulf of California and the Pacific coast of Mexico, and birds from central Canada, the Dakotas, Colorado, Minnesota and Montana following the Missouri and Mississippi River drainages to the Gulf of Mexico coasts, Florida and Central America. Pelicans banded at breeding colonies in Utah and Wyoming were recovered along both routes, with some evidence of a third pathway suggested for these birds along the western slope of the Rockies. The only region of substantial overlap in returns between birds banded in the western breeding colonies and those from mid-western breeding colonies (east of the North American Continental Divide) was in southern Mexico and Texas. Returns from Central America consisted almost exclusively of American White Pelicans banded in the eastern portion of the breeding range.