U.S. Army Corps of Engineers – Walla Walla District Impacts of Avian Predation on Salmonid Smolts from the Columbia and Snake Rivers 2004-2009 Synthesis Report 2004-2009 SYNTHESIS REPORT IMPACTS OF AVIAN PREDATION ON SALMONID SMOLTS FROM THE COLUMBIA AND SNAKE RIVERS This 2004-2009 Synthesis Report has been prepared for the U.S. Army Corps of Engineers – Walla Walla District for the purpose of assessing project accomplishments. This report is not for citation without permission of the authors. Prepared by Daniel D. Roby, Principal Investigator USGS - Oregon Cooperative Fish and Wildlife Research Unit Department of Fisheries and Wildlife Oregon State University Corvallis, Oregon 97331-3803 Internet:
[email protected] Telephone: 541-737-1955 Ken Collis, Co-Principal Investigator Real Time Research, Inc. 52 S.W. Roosevelt Ave. Bend, Oregon 97702 Internet:
[email protected] Telephone: 541-382-3836 Donald E. Lyons, Jessica Y. Adkins, Peter Loschl, Yasuko Suzuki, Tim Marcella, and Lauren Kerr USGS - Oregon Cooperative Fish and Wildlife Research Unit Department of Fisheries and Wildlife Oregon State University Corvallis, Oregon 97331-3803 2 Allen Evans, Bradley Cramer, and Nathan Hostetter Real Time Research, Inc. 52 S.W. Roosevelt Ave. Bend, Oregon 97702 Benjamin P. Sandford, Richard D. Ledgerwood, and David R. Kuligowski Fish Ecology Division, Northwest Fisheries Science Center, National Oceanic and Atmospheric Administration, 2725 Montlake Boulevard, Seattle, Washington 98112-2097 Scott Sebring Pacific States Marine Fisheries Commission 205 Southeast Spokane Street, Suite 100, Portland, OR 97202 Submitted and Revised: October 2011 3 TABLE OF CONTENTS EXECUTIVE SUMMARY………………………………………………………….. 5 CHAPTER 1: COLONY SIZE, NESTING SUCCESS, AND LIMITING FACTORS OF PISCIVOROUS COLONIAL WATERBIRDS IN THE COLUMBIA PLATEAU REGION, 2004-2009……………………………………..