Introduction: Biology and Conservation of the American White Pelican

—Two separate, large-scale management units for the American White Pelican ( Pelecanus erythrorhynchos ) in North America are proposed: the eastern and western metapopulations, separated by the North American Continental Divide. The populations on either side of this barrier are subject to contrasting ecological conditions, movement patterns suggest strong geographic separation and each is likely demographically distinct. Subdivisions within these demographic units need to be more precisely defined in the future. Yet, because of the highly colonial nesting habits of the American White Pelican, conservation can still be effective if directed toward separate breeding colonies. Our intent is to provide a compilation of current knowledge regarding species status, distribution and ecology. Herein, further study is recommended: (1) to determine genetic characteristics and the degree of genetic separation of the various geographic divisions in the range of the species to help ultimately better define “evolutionarily significant units” for American White Pelican conservation, (2) to study movements and genetic exchange among and between these divisions, and (3) to study movement patterns and genetic mixing among these divisions during longand short-term changes in environmental conditions.