Project Sponsor: 

 U.S. Fish and Wildlife Service 



Brad J. Bortner and Tara S. Zimmerman 



Division of Migratory Bird Management 



Portland, Oregon 



Editorial Assistance: 

 U.S. Geological Survey 



Dennis L. Orthmeyer 



Western Ecological Research Center 



Dixon Field Station 



Dixon, California 



Jerry D. Cox 



Upper Midwest Environmental Sciences Center 

 Onalaska, Wisconsin 



Publication Costs: 

 U.S. Fish and Wildlife Service 



Division of Migratory Bird Management 



U.S. Geological Survey 



Western Ecological Research Center 



Apex Houston Trustee Council 



California Department of Fish and Game, Office of Spill Prevention and Response 



U.S. Fish and Wildlife Service, Ecological Services, Sacramento, California 



National Oceanic and Atmospheric Administration 



Gulf of the Farallones National Marine Sanctuary 



uses 



science for a changing world 



IX 



